1. Optimization of a Novel Algal Oil
Harvesting Strategy for Renewable
Biofuels
James Madison University
May 2016
Written by: Hannah Aloumouati, Victoria Foster, McKinnon Langston and Alexander Macfarlane
Advisor: Dr. Chris Bachmann, Ph. D

2. Table of Contents
Abstract........................................................................................................................................... 3
1.0 Introduction............................................................................................................................... 4
1.1 Petroleum Dependence............................................................................................................ 4
1.2 Algae-Based Biofuels............................................................................................................. 10
1.3 Environmental Concerns....................................................................................................... 11
1.4 Objectives.............................................................................................................................. 14
2.0 Methodology............................................................................................................................. 15
2.1 Algae Cultivation................................................................................................................... 15
2.2 Harvesting............................................................................................................................. 19
2.3 Separation of End Products ................................................................................................... 24
2.4 Algae Oil Purification and Solvent Reclamation..................................................................... 26
2.5 Algae Oil Quantification........................................................................................................ 27
2.6 Determination of Energy Input vs. Output (need kilowatt meter photo) ................................... 28
2.7 Mathematical Modeling of Theoretical Algae Oil Yields ......................................................... 29
2.8 Cost Analysis......................................................................................................................... 29
3.0 Results...................................................................................................................................... 30
4.0 Discussion................................................................................................................................. 34
4.1 Unintended Consequences..................................................................................................... 38
5.0 Conclusion................................................................................................................................ 39
6.0 Current and Future Direction of Research............................................................................... 39
References...................................................................................................................................... 42

3. Abstract
The United States Environmental Protection Agency has determined that the transportation sector was
responsible for 27% of U.S. Greenhouse Gas Emissions in 2013. To reduce emissions released into the
atmosphere, The U.S. Department of Energy (DOE) is funding research for “Advanced Biofuels” that are
less harmful to the environment. The use of algae as a biofuel feedstock has attracted considerable
attention because of its potential to provide abundant, clean, renewable fuel that does not interfere with
the global food supply. The DOE’s National Algal Biofuels Technology Roadmap identifies two main
problem areas that need to be overcome for algae biofuels to become economically viable: large-scale
algae production and algae harvesting. This project focuses on the optimization of a novel, energy
efficient and cost effective algae harvesting method. This method was developed through a public-private
partnership between James Madison University and Wholesome Energy of Edinburgh, VA. The process
uses extremely high shear mixing in the presence of a powerful non-polar solvent to breakdown algae cell
membranes and facilitate migration of oil into the solvent phase. The algae oil is then purified from the
solvent and the solvent is recycled back into the extraction process. Preliminary data for the harvester
shows approximately 29,500 gallons of seawater culture media are needed to produce 1 gallon of algae
oil. At current operating conditions, this small scale harvester would need to run for 28.5 days
continuously at a cost to harvest at $0.31 per day, yielding a total cost to harvest the raw algae oil at $6.08
per gallon. Despite this process’s costly production, further investigations to improve the overall energy
and cost efficiency are currently underway. This algae-oil harvesting strategy could potentially be used to
facilitate the cleanup of harmful algae blooms in the Chesapeake Bay by providing an economic incentive
for algae collection. When combined with offshore algae cultivation, this system has the potential to
provide abundant clean renewable fuel not only to Virginia, but also to other parts of the United States.
This results in significant reductions in harmful greenhouse gas emissions from the transportation sector.

4. 1.0 Introduction
As the world population steadily increases, the rate of consumption steadily increases as well [1]
.
Consumption is inevitable. The consumed resources cradled from the environment range from simple
food products to highly energy intensive fuels. A major stepping stone in today’s society is the need for
an abundant clean energy resource that can supply the demand of the current population without
impairing that of future generations [2]
. Something to consider with this is that the economic feasibility of
an energy source is a heavily weighted parameter in the widespread adoption of a fuel. Other parameters
include social acceptance, molding to current infrastructure, stakeholders, environmental soundness, and
others. Current energy resources are in favor of fuel powering sources like coal, oil, and natural gas that
can each have detrimental impacts on the environment and impede the societal and environmental
development of future populations. Fossil fuels are low cost, abundant, easily accessible, and have more
than 100 years of development behind their extraction, refinement, distribution, and end-use. There aren’t
many options that can compete, or even be able to meet demand, let alone be cost competitive. Despite
the consequences learned from the utilization of these fuels, accessibility, low cost and infrastructure
allow its use to continue. An intermediary solution to this could be the use of algae microorganisms to
produce biodiesel that can be utilized as a fuel source, particularly the transportation sector [3]
. Not only
does this fuel source provide the same energy content as that of diesel fuel, but it also is almost a carbon
neutral source, it does not disrupt the global food supply to produce, it has a doubling rate of about 48
hours for constant production, and most importantly, it fits the current liquid fuel infrastructure already
established in the United States. This report assesses the promise and opportunity algae biodiesel has to
offer for a sustainable development.
1.1 Petroleum Dependence
Research of algae as a fuel source has been under development since the 1920s and currently, the 2010
National Algae Biofuels Technology Roadmap identifies algae cultivation and harvesting as two main
problem areas with algae biofuels [4]
. This thesis specifically focuses on optimizing a novel harvesting
method for algae crude oil.
It’s the United States addiction to oil that is preventing the prosperity of an alternative fuel source that is
better environmentally. Oil has not always been the staple fuel source utilized predominantly in the
United States by various end-use sectors. Coal was once the primary fuel to supply energy to each sector,
and currently it is most widely used to generate electricity [5]
. Coal’s abundance and known attributes
enabled its progressive use throughout the United States. The addiction to oil sprang from the Industrial
Revolution, where a cheaper, more accessible fossil fuel was needed to substitute coal [6]
. Oil became this
primary fuel source for many reasons. It has become the main source for fuel in civilization for reasons
such as its social needs and demands, influence of corporate stakeholders, the physical traits of oil, and
the dominance of oil as the premier energy source for the transportation sector. Around the mid-1800s oil
became the fossil fuel that everyone began to try and locate. Due to this need the oil industry started to
really succeed in the mid to late 1800s. Edwin L. Drake was hired by an American entrepreneur named
George Bissel to locate this oil [6]
. Drake was hired, by Bissel’s Pennsylvania Rock Oil Company of New
York, to drill for oil near a well-known oil seep on Oil Creek in Titusville, Pennsylvania [6]
.The refined

5. crude oil extracted from the ground began to produce a byproduct called Kerosene [7]
. One of the first
American uses for oil was this byproduct [7]
. Kerosene was used during the American Civil War from
1861-1865 to provide light and heat in the form of a gas lamp [7]
. Thomas Edison’s invention of the light
bulb soon impacted the use of Kerosene for light [8]
. This allowed the paradigm to shift from oil being
used as a light source, to oil being used for gasoline. As the next few decades approached,an entrepreneur
by the name of John D. Rockefeller began to understand the need for oil and its impact on the American
economy [8]
.
At the age of 16, John D. Rockefeller began to recognize the importance and dependence of oil and its
impact on the American economy [9]
. He was a bookkeeper for a produce company and began to save his
money for future investments into the prominence of oil [9]
. In 1859 Rockefeller invested into a Cleveland
based oil refinery [9]
. By 1865 Rockefeller had begun to recognize the successful growth of this refinery
and he proceeded to take out a loan to buy out his partners [9]
. Rockefeller now controlled the largest oil
refinery in Cleveland [9]
. In the coming years, Rockefeller expanded his entrepreneurship ideas in the oil
industry. In 1870 he started his own company, Standard Oil Company. Standard Oil Company used the
ability to market, produce, transport, and refine petroleum better than any competitor [9]
. By 1882
Rockefeller's Standard Oil Company became a monopoly to the oil market [9]
. Americans felt this threat
of the monopoly and took government action to address the situation. The federal government passed a
legislative act called the Sherman Anti-Trust Act in 1890 [10]
. This act was passed by the United States
Congress and gave them the ability based on the constitutional power of Congress to regulate interstate
commerce [10}
. The Sherman Anti-Trust Act was used against Rockefeller’s company and through many
legal battles, Standard Oil Company began to dissipate. In 1904, Standard Oil Company still controlled
91% of oil production and 85% of its final sales [11]
. It took until 1911 that Standard Oil Company was
completely dissolved by the Sherman Anti-Trust Act into 34 smaller companies [9}
. Companies that are
around today were created due to this act such as the following: Amoco, Exxon, Marathon Oil, and
Mobile.
Around the 1800s, when a more effective and faster transportation method was needed to stray away from
the horse and buggy, three main fuel types emerged: steam, electric, and gasoline {12}
. Each of these
vehicle types had the chance to prosper in the United States but the gasoline/oil based engine dominated
because it was cheap abundant, reliable, was faster to refuel, and range anxiety wasn’t an issue compared
to the other fuel types. The internal combustion engine forever changed the demand for coal fuel supplies
as well [13]
. Entrepreneurs began to see the opportunity in gasoline and oil. In the 1900s, Henry Ford
established his Ford Motor Company, and five years later, the company released their Model T gasoline
engine vehicle [14]
. Before Ford, cars were seen as a luxury to Americans where only wealthy people
could afford them. Once Henry Ford constructed and mastered the assembly line to mass produce his
Model T product, the demand for the cars steadily rose, bringing the price of this vehicle down. This
process provided the gasoline/oil internal combustion engine with a very advantageous position in the
market, wiping other fuel types from prospering as greatly.
Due to the influence of John D. Rockefeller and Henry Ford businesses, the American oil industry began
to grow rapidly. Since Henry Ford’s Model T had an internal combustion engine, the oil market continued
strong into the early parts of the 1900s. Ford’s assembly line and production of car changed the landscape
of the oil industry. Cars were becoming more prevalent and the supply and demand for oil needed to be

6. met somehow. An accommodation for this need had to be met to address this rapid growth. American oil
companies continued to grow and the need for an American infrastructure to support it had to be met. Not
only were there oil wells and companies popping up everywhere, the ability to ship and transport this
crude oil needed to be met. By the advent of World War I, crude oil pipelines were starting to transverse
the United States [15]
. Driven by the rapid growth of the automobile industry, pipelines were starting to
form the foundation of the oil infrastructure. In 1920, there were approximately 115,000 miles of oil
pipelines across the country [15]
. Pipelines began expanding westward in the 1930s due to population
growth west of the Mississippi. Throughout World War II the pipeline infrastructure grew rapidly. The
United States had 48 oil tankers sunk during this war, mainly along the eastern seaboard [15]
. America
addressed this by creating land based pipelines that began to pump oil from states such as Texas and
Oklahoma [15]
. These were large-diameter pipelines carrying crude oil to East Coast consumer states [15]
.
This foundation infrastructure laid back then is still the current one we use today, with some
modifications to fit current technology [15]
. In 2015, according to the United States Department of
Transportation, there was over 1.7 million miles of gas and oil pipelines [16]
. Everything in this oil
industry, down to the gas pumps that put gas in our vehicles, is a direct correlation of the global influence
of oil as a fuel source. The fuel source’s base product is oil, allowing the industry to continue its growth.
Up until 1910s, the United States produced between 60-70% of the world’s oil supply [17]
. With the large
supply, there was concern for the U.S. supply being diminished. In 1908 Theodore Roosevelt brought this
concern to the forefront and appointed the National Conservation Commission (NCC) to take an
inventory of America’s natural resources and to discover areas where egregious waste was occurring [18]
.
When the NCC delivered its findings to Congress in 1909, it reported that the nation’s petroleum supply
would last a mere 25 to 30 more years [18]
. This generated a fear throughout America, forcing them to turn
to foreign countries. As Americans were scared the nation’s petroleum supply was diminishing, countries
like Mexico, Iraq, Iran, and Venezuela were beginning to discover more oil. Shortly after this in 1924,
Texas, Oklahoma, and California experienced an oil boom that mitigated America’s oil scare [19]
. This oil
boom actually brought oil pricing plummeting down to ten cents a barrel and regulations had to be set to
raise these prices back up. From this stemmed OPEC (Organization of Petroleum Exporting Countries),
which was created to help manage oil exportation and prevent oil prices from ever plummeting again.
In 1954, Marion King Hubbert, working for Shell Oil at the time, developed a peak oil curve for the
United States oil production [20]
. This curve incorporated cumulative oil production, proven oil reserves
and future discoveries all as a bell shaped curve shown in the figure below. From his findings, he
predicted that the United States oil production would peak in the year 1970 [20]
. During this time, a lot of
people argued back and forth on whether or not the U.S. would run out of oil. Hubbert was just another
opinion to add to this pot, so his findings were not taken seriously. This time period also saw a popularity
of the muscle cars and gas guzzlers in America. With the combination of these vehicles and rates of
consumption increasing, the U.S. did in fact reach a peak in their production in the year 1970 as Hubbert
predicted. Three years later, the U.S. experienced its first oil crisis.

7. The 1973 Oil Crisis is most widely known as the Arab Oil Embargo. On October 6th, 1973, Egypt and
Syria launched a surprise military campaign against Israel, and six days later, the U.S. provided aid to
Israel. In response to the U.S. supply Israel with aid, OPEC, consisting of Saudi Arabia, Iran, Iraq, Abu
Dhabi, Kuwait, and Qatar at this time, announced an oil embargo against Canada, Japan, The
Netherlands, United Kingdom and the United States [21]
. This raised the price of oil by about 70%,
sending these countries into an oil shock [21]
. When the U.S. could not manage any longer, the Nixon
Administration negotiated and convinced Israel to withdraw its forces and pull back [21]
. Shortly after, the
Arab Oil Ministers lifted the embargo in December 1974, ending the crash of the stock market [21]
.
After the oil crisis, Hubbert continued his research on oil production but instead, he analyzed a global
perspective. From his research, Hubbert then predicted that there would be a global oil production peak in
1995 if the current rate of consumption continued [20]
. Soon after this prediction was released, a second oil
crisis erupted in the United States. The 1978 oil crisis was the results of a decreased oil output from its
foreign imports in the wake of the Iranian Revolution [21]
. The global oil supply only decreased by about
4% but the widespread panic in the U.S. is what drove the price per barrel far higher than justified by the
supply. The price per barrel more than doubled and odd-even rationing had to be implemented in the
states [21]
. Odd-even rationing meant that Americans could only get gas on certain days of the week based
off of their license plate number. Sometimes they were even limited by how much gasoline they could
purchase. This crisis clearly distinguished the United States vulnerability to foreign oil supply. A
management council was needed to promote U.S. energy independence by further diversifying its energy
portfolio.
The ideas of creating a department to address this energy portfolio dated back to before World War I.
Albert Einstein helped promote these ideas by handwriting a letter to President Theodore Roosevelt
explaining the importance of nuclear chain reactions and the possibility that it might lead to the
Figure 1.1.1: Hubbert’s peak concept is demonstrated by this figure. This image
illustrates the concept of increased oil discovery, followed by increased oil
extraction, then a rapid decline in production as oil reserves are depleted at a
maximal extraction rate. Image by www.agorafinacial.com

8. production of powerful bombs [22]
. Many energy programs were created to address this and projects such
as the Manhattan Project was formed in late 1941 [22]
. The Manhattan Project was the codename for an
American project that had aspirations of designing and building the first atomic bomb. Projects such as
the Manhattan Project continued to arise and be completed with no form of federal government policy.
This became something that America needed to address and President Jimmy Carter took this idea
seriously. He was inaugurated President of the United States in January of 1977, and addressed the need
to put Federal energy activities under one umbrella and provided the framework for a national energy plan
[22]
. Through his efforts, The Department of Energy was formed in August of 1977 [22]
. This department
combined most of these government energy programs, but also addressed defense responsibilities that
include the design, construction, and testing of nuclear weapons.
The Office of Fuels Development was one of the government energy programs that now fell under the
Department of Energy umbrella. They wanted to create a program to develop renewable fuels for
transportation from algae. The end result of this want was the Aquatic Species Program being started in
1978 [3]
. The main focus of this program was to achieve the production of biodiesel from high lipid-
content algae grown in ponds while utilizing waste carbon dioxide from coal fired power plants [3]
.
Researchers in the Aquatic Species Program wanted to identify specific algae strains that had high lipid
content along with being able to survive in severe conditions [3]
. The conditions that concerned them the
most were the temperature, pH, and salinity of the water. The researchers collected over 3000 strains of
algae across the continental US and Hawaii [23]
. After screening, isolation, and characterization efforts the
collection was reduced to 300 strains [23]
. Between 1978 and 1982 the research efforts of this program
were designated to use the algae strains to produce hydrogen [3]
. The program then switched its efforts to
transportation fuels and more specifically biodiesel for the rest of its existence. Funding began to become
difficult for this program due to the federal government’s idea of downsizing. Not only did funding play a
vital role on the Aquatic Species Program but so did the price of oil. In the 1980s and 1990s oil prices
began to fall and the need to find an alternative fuel source was not at the forefront of Americans minds.
In 1996 the Aquatic Species Program was shut down closing a program that once seemed so promising [3]
.
The program concluded that the production of microalgae used for fuels is not limited by engineering
designs, but by the many microalgae cultivation issues [3]
. The issues ranged from species control in large
outdoor systems, to harvesting and lipid accumulation, to overall productivity [3]
. Once this program was
shut down, the focus on the bioethanol sector began to grow.
At the turn of the century, oil prices were still low but due to political issues, they were steadily rising.
The U.S. was importing about 75% of its total oil consumption and its oil production was declining,
which is shown in the graphical figure below generated by the EIA.

9. The United States saw this as an energy security issue and knew they were still vulnerable to foreign oil
supplies. At this time, Iraq had the second largest oil reserve in the world behind Saudi Arabia, whom was
America’s ally. In 2003, the U.S. invaded Iraq ultimately because the U.S. was fearful of Iraq possessing
weapons of mass destruction and the public perception of Iraq having an influence on the attack on
September 11, 2001. One of the primary goals of this invasion was to secure Iraq’s oil fields and
resources by ending the regime of Saddam Hussein. The U.S. wanted to give Iraq’s oil reserves back to
the Iraqi citizens to not only promote the economic health of Iraq, but also create an ally in them as well.
In the meantime, the U.S. reliance on foreign fuels increased with their position in war. This brought
about the 2005 Energy Policy Act that was passed on July 29th by Congress and George W. Bush [24]
.
Some general provisions of this act included exempting all fluids used in the natural gas extraction
process from the protections under the Clean Air Act, Clean Water Act, Safe Drinking Water Act, and
CERCLA, it increased the amount of biofuels (usually ethanol) that must be mixed with gasoline sold in
the U.S., it seeks to increase coal as an energy source while also reducing air pollution, authorizing $200
million annually for clean coal initiatives, it gives a tax credit to renewable energy producers, and as well
as many other provisions [24]
. One of the provisions of this act was for the U.S. to have 25% of renewable
energy used by end-users in the U.S. by the year 2025 [24]
. This was a goal and not necessarily a mandate,
but agencies like the Department of Navy and the Department of Energy aggressively wanted to achieve
this goal. This facilitated the establishment of a Renewable Energy Strategy that helped promote research
and adoption of renewable energy sources. This act also influenced a larger production of ethanol,
stimulating 27 new ethanol plants, 401 new E85 gas pumps installed, and in 2006 1.4 billion barrels of
ethanol was produced [25]
.
Figure 1.1.2: This is a graph of U.S. crude oil production and oil imports for the
U.S. generated by the EIA. Notice how the production in the U.S. steadily
declines due to supply issues and imports increase. Then production increases
around the same time hydraulic fracturing takes off and imports steadily decline.

10. The production of ethanol skyrocketed, while it also met its intended goals. This contributed to EISA, the
Energy Independence and Security Act of 2007. This mainly encouraged a higher fuel standard for fleets
of vehicles, more efficient home appliances, and it also set up regional standards for heating and cooling
throughout the United States [26]
. The stated purpose of this act was to “...move the United States toward a
greater energy independence and security…” [26]
. The original bill sought to cut subsidies on the
petroleum industry in order to promote petroleum independence, but this was quickly dropped due to the
industry’s stakeholders and influence. Instead the Renewable Fuel Standards was adopted, requiring
transportation fuel sold in the U.S. to contain a minimum of 36 billion gallons of renewable fuels,
including advanced and cellulosic biofuels and biomass-based diesel by 2022 [27]
. Since ethanol
production was already increasing and meetings its intended goals, stimulating its production even further
was not an issue.
Today, 93% of the transportation sector is dependent on oil use, 70% of all oil products goes to
transportation and about 36% of the total energy demand is met from oil in the United States [28]
. Since
the overall need and use of oil has increased throughout the years, the United States is working diligently
to increase their energy independence by finding more sources of oil nationally. There are over 4,000
offshore drilling rigs in Texas, Alaska, and California, making up approximately 35% of the total
domestic oil production in the United States [29]
. For the United States to achieve energy independence
from foreign oil imports, the total domestic production must exceed that of the total imports. Looking
closer at the U.S. and global oil supply, we have a larger supply than ever before. The image below was
taken from a BP Statistical Review, where you can clearly see the supply increasing over the years. There
is an even bigger supply jump from the year 2001 to 2011. This can largely be attributed to the hydraulic
fracturing extraction process. This is commonly used to extract natural gas, but it is also just as effective
to extracting oil supplies. Since the 2005 Energy Policy Act exempting all fluids used in this process from
regulation, this process became a lot more enticing to utilize for oil harvesting. Now that the U.S. and
world has a large supply of oil, the main reason to switch to an alternative fuel isn’t a matter of a
diminishing supply, but more so a large concern for the health of our environment and its implications on
future generations.
1.2 Algae-Based Biofuels
With the ability to adapt to circumstances along with its rapid growth and doubling rate, algae was used
for many research efforts. One of the early use by American researchers of algae, was to provide a food
source. In 1948, researchers had the idea that algae could end world hunger. After World War II there
were impoverished and malnourished people across the world. Researched used Chlorella as this strain of
algae to end world hunger. When grown in optimal conditions—sunny, warm, shallow ponds fed by
simple CO2
—Chlorella converted around 20% of available solar energy into plant biomass containing
over 50% protein when dried [30]
. The problem with Chlorella is that it was a very temperamental strain of
algae that was not sustainable. Also the thick cell walls of Chlorella made it indigestible without a very
cost and energy intensive mechanical process [30]
. The research gave up their push to end world hunger
and algae began to be used to produce other things such as a gas and biofuels [30]
.
The production of methane gas from microalgae dates back to 1950. A professor at the University of
California-Berkeley used microalgae to produce methane gas by anaerobic digestion, better known as

11. fermentation [31]
. The energy crisis in 1973 gave the research of microalgae into gaseous fuels (hydrogen
and methane) momentum that grew the idea of turning microalgae into biofuel [31]
. The Department of
Energy (DOE) was formed in August of 1977 and helped microalgae research thrive. The Aquatic Species
Program was started under the DOE in 1980 and research efforts were used to produce algae based
biofuels for the transportation sector [3]
. Initial efforts were to produce hydrogen gas, but then quickly
switched to transportations fuels and more specifically biodiesel [3]
. Once this program was shut down in
1996, the private sector for algae research needed to take on the responsibility of using algae as a biofuel
source. During the 1990s, the Japanese government supported a major program on algae for CO2 capture
and greenhouse gas abatement, with a budget of more than $250 million dollars [31]
.
Currently the private sector along with the DOE are starting to realize the need for an algae based biofuel.
Companies such as British Petroleum and Exxon have put aside millions of dollars for research
investments [31]
. The National Algal Associations and the Algal Biomass Organization are two of the main
research groups in America [31]
. A huge need for an alternative fuel needed to be sought out since the
transportation sector is responsible for 34% of all CO2 emissions in the United States and transportation
sector uses oil [32]
.
1.3 Environmental Concerns
While the fossil fuels reserves are continuing to expand as newer technologies make it possible to access
fuel that was previously thought to be unattainable, the need for alternative fuels stems from the impact
that fossils fuels has on our environment. The transportation sector is responsible for 34% of all CO2
emissions in the United States and transportation sector uses oil [32]
. Though abundant, these fuels are
anything but clean and are responsible for negative environmental impacts throughout their lifecycle.
The production and use of oil has many external and indirect costs [33]
. The first being the extraction of
the oil. The ability to access locations of oil has become more difficult as previous wells have dried up.
This has caused oil producers to take extreme measures to retrieve oil, in turn, increasing the risk of the
process. The Deepwater Horizon oil leak is an example of this associated risk. Over 200 million gallons
of crude oil leaked into the Gulf of Mexico, impacting aquatic life for thousands of shoreline miles and
directly affecting the local economies [34]
.
Next is the transportation of the fuel. Only a few countries produce a majority of the world's oil which
means most of the oil is exported. This creates opportunity for disaster to occur during its transportation.
An example of this disaster is the Exxon Valdez oil spill in 1989. An oil tanker on route to California,
collided with an Alaskan reef, causing 38 million gallons of crude oil to be spilled. This was considered
to be one of the most devastating human-caused environmental disasters of its time, which now pales in
comparison to the BP oil leak [34]
.
All of these are examples of issues with petroleum before its consumption. But when the oil is finally
combusted, toxic chemicals and carcinogenic soot is released into the environment, leading to lung
disease, lung cancer, asthma, and increased mortality rates [35]
. These issues all contribute to the
degradation of the environment, but the largest issue with fossil fuels is by far the excessive
anthropogenic CO2 released into the atmosphere, eventually giving way to Global Climate Change.

12. Since the Industrial Revolution began around 1750, human activities have contributed substantially to
climate change by adding CO2 and other heat-trapping gases to the atmosphere through the burning of
fossil fuels [36]
. Currently human activities release over 30 billion tons of CO2 into the atmosphere every
year. 34% of these CO2 emissions come from the transportation sector alone [36]
. These greenhouse gas
emissions have increased the greenhouse effect and caused Earth’s surface temperature to rise [37]
. 2015
was the hottest year in recorded history and Scientists at the National Snow and Ice Data Centre said that
this March the sea ice cover reached the lowest winter maximum since records began in 1979 [38]
. Not
only is the increase in temperature melting arctic more than has been recorded. But this massive melting
is predicted to lead to a six foot sea level rise by the end of the century [39]
.
Current consumption of fossil fuels has caused carbon dioxide levels to increase drastically, in turn
increasing the amount of greenhouse gas present in Earth’s atmosphere causing global climate change.
Regardless of the known consequences and effects of global climate change, very little legal action has
been taken to restrict or limit use of fossil fuels. The matter of fact is that most people who use fossil fuels
are aware of the environmental consequences but refuse to take action on a personal level. That is why
creating a renewable fuel source that consumes the CO2 it creates from combustion is a feasible reason to
implement it on a full scale.
Figure 1.3.1:This graph displays the rate of change of sea level that occurs per year
and future projections. 52% of the nation’s population lives in coastal region so sea
level rise is understandably of high concern to the United States [40]
. Flooding in
these communities on the coast could lead to a displacement of 13 million people in
the US by 2100 [41]
. This massive relocation would not only cause serious tension in
the nation, but would also create monumental disruptions along the shipping trade
routes [42]
.

13. In addition to consuming CO2, the areas where salt water algae can be grown help save terrestrial
ecosystems from being destroyed. Due to its ability to be cultured offshore, algae does not require land to
be cleared like certain energy sources, like solar power, do. Not only does this benefit the environment,
but the offshore culturing of algae does not take away from any land being used for agriculture. While the
impact of marine ecosystems may seem an issue at first, there are many dead zones in the ocean that have
little to no known life existing there and these dead zones could be a safe environment to grow algae for
biofuel.
The increase in CO2 levels have led to an increase in such natural disasters as fires, droughts, hurricanes,
floods, and acid rain. Acid rain kills fish, alters ecosystems, and decreases biodiversity [43]
. It can also
harm people through the atmosphere or through the food chain by having crops grown in the toxic soil,
animals consumed by humans, and by drinking water [43]
. The acidifications of the oceans due to CO2
levels has dropped by 0.1 units since the industrial revolution and is predicted to drop by a further 0.3–0.4
units by 2100 [44]
. This has led to major destruction and bleaching of coral reefs [44]
. Currently over 93
percent of the Great Barrier Reef is bleached [44]
. Due to all the negative environmental impacts spurred
by the usage of fossil fuels, an environmentally friendly fuel needs to be implemented.
The DOE and DON has already began research for several of these possible transportation alternatives
but to insure the success of any alternative fuel, we must address the social and environmental impacts
that may come with them. Below is a list of several possible alternative fuels as well as their advantages
and disadvantages.
Figure 1.3.2: This chart compares several alternative transportation fuels that the Depart of Energy
and Department of Navy have considered pursuing. Biodiesel has many advantages that make it a
more feasible option than other alternatives.

14. Using algae oil as a transportation alternative poses many advantages that trump other options. There are
disadvantages to using algae but we believe that with the continuation of research into algae cultivation
and harvesting methods, algae oil will become a successful alternative.
1.4 Objectives
In order to produce an image for the acceptance of algae produced oils for fuel usage, it was necessary to
review all relevant information currently dedicated for algae based biofuels studies relevant to this
specific report. As this report analyzes the optimization of algal oil harvesting by manipulating various
parameters within the emulsification process, the solution can be seen as a conformational change to the
process itself or a need for change within the mechanics of the system. Based on the research, the latest
developments and future direction of this research, basic knowledge of this subject and societal issues that
will influence the successful adoption of the project are evaluated. Research efforts were started by
recognizing the two main issues with algae biodiesel identified in the 2010 National Algae Biofuels
Technology Roadmap. These issues were the harvesting and cultivation issues with algae [4]
. The
Department of Energy through the report: A Look Back at the U.S. Department of Energy’s Aquatic
Species Program: Biodiesel from Algae, developed a list of algae strains that had high-lipid content thus
allowing us to receive high oil yields [3]
. Nannochloropsis was chosen as this strain. In continuing
research, there had to be a proper technique to harvest this algae. The current methods were very energy
intensive and required a time consuming dewatering step. This research effort focuses on a process that
does not require dewatering. The emulsification process of the Nannochloropsis did not require
dewatering and thus was chosen for the optimization effort on harvesting the algae. Emulsification is a
process of high-shear mixing of n-Hexane with the saltwater algae volume that makes the algae cell walls
break apart releasing an oil that is collected through a reclamation device. Many efforts to produce algae
biodiesel have been sought out, but the cultivation and harvesting issues identified in the 2010 National
Algae Biofuels Technology Roadmap deem too large of an obstacle to make this an energy and cost
efficient task.
This project sought to optimize the harvesting process of algae in order to achieve a higher and more cost
competitive algal oil yield. The steps implemented to optimize the system were finding the ideal flow rate
and a single pass system. An energy cost analysis was conducted on the harvester to understand the
energy input. A single pass system was implemented to reduce the time the system was operating and
therefore lower energy input. Regulating the input of the solvent n-Hexane was accomplished through
introduction of a turn valve. The rest of this report includes methodology and results of the experiment.
The goal of this experiment is to calculate the cost of the amount of energy obtained, to compare it to the
amount of energy that was put into the system. In doing so, a series of lab experiments were conducted to
obtain a fuel that could potentially be a more sustainable energy source then current practices. Despite
sustainability being a very desirable factor, economic feasibility is a more important aspect within the
adoption process of a new fuel source. To calculate the cost to produce this algae oil fuel source at this

15. maximum rate of production for a comparison to current market fuel sources, the harvester’s energy usage
was recorded using a kilowatt reader during the harvesting phase.
2.0 Methodology
In order to obtain notable results, the follow methods were performed during the length of this
project. Each major area of focus is divided into subsections to explain in detail how this project
was conducted.
2.1 Algae Cultivation
To create and retrieve algae oil, our project uses three distinct processes, the first being algae cultivation.
Before the processing of algae cells can occur, the culture itself must be grown to the adequate size, then
maintained and monitored. Nannochloropsis was chosen because it has a high oil yield compared to other
strains and is a species of saltwater algae which can be grown offshore to cultivate large volumes.
Nannochloropsis requires a consistent environment to grow in and the optimal environment being an
aqueous solution with a salinity of approximately 37 parts per thousand [45]
. To achieve optimal salinity,
Instant Ocean Aquarium Salt was purchased and mixed with onsite water. A salinity curve was made by a
previous algae capstone group which provided our team with an equation to gage how many grams of salt
was needed for a desired amount of water. Once the measured salt is added to water, it needs to be
thoroughly mixed to dissolve. The salinity needs to be measured after mixing to ensure that proper
amounts of salt and water were mixed, this is done by using a refractometer which gauges the refractivity
of a solution based on its salt content Show picture of refractometer After the desired salinity is reached,
optimal temperature must be reached.
The temperature of the algae is another factor that needs to be controlled. Algae can experience a “shock”
when there is a drastic change in the surrounding environment. Large fluctuations of salinity or
temperature can shock the algae, causing large amounts of algae cells to die-off. To maintain our cultures
temperature, four aquarium heaters set to 75 degrees Fahrenheit were added to the culture tub. This
temperature mimics the oceans equatorial temperatures to reassure healthy rapid growth of the algae.
An important factor for algae growth is the strength and duration of light exposure. Since our culture was
grown indoors to maintain a consistent environment, plant grow lights were needed. The previous algae
capstone team under the advisement of Dr. Christopher Bachmann obtained grow lights, one being a 600
Watt Metal Halide light and the other a 1000 Watt High Pressure Sodium light.

16. To control light duration, two electrical timers were purchased and set to turn on for a 12 hour period
every 24 hours. This time frame was chosen to maximize cell growth by imitating the light exposure algae
would receive near the equator.
Algae also requires agitation to thoroughly mix the cells exposing them to necessary nutrient and carbon
dioxide. Three aquarium pumps were purchased and placed inside our culture tub to properly mix the
water. These pumps naturally collect algae cells over time and need to be cleaned once a month to reduce
risk of becoming defective.
After a controlled environment has been set up, algae cells can be introduced. To obtain the culture of
Nannochloropsis algae, our team purchased several 100 milliliter vials from Carolina Biological.
Figure 2.1.1: A 600 watt metal halide and
1000 watt high pressure sodium light are used
to grow our algae cells. They are controlled by
timers to turn on for 12 hours daily.
Figure 2.1.2: Nannochloropsis algae is grown
by Carolina Biological and available for
purchase. Our team purchased several 100
milliliter vials to begin algae cultivation.

17. This amount alone will not be enough to extract a significant amount of oil. To harvest the algae, four
gallons of algae culture is needed and to run a trial, twelve gallons is required. Once we received the algae
it needed to be grown to a larger size which we deemed “size up”.
Nannochloropsis cells double every 48 hours, which allows for a size up to be done every 48 hours. A
size up consists of two factors, saltwater and nutrients. The saltwater is a medium for algae to grow in,
allowing new cells to populate it, while the nutrient provides necessary resources for cells to grow and
divide. To double the algae culture volume, equal parts salt water and algae culture must be mixed with
appropriate amounts of nutrient. This size up process was done every other day until we cultured 120
gallons of saltwater algae. This amount allows our team to process several runs of algae a week and any
algae removed for processing is regrown by sizing up.
To ensure the health of our 120 gallon culture, an automated top-off system was created. Fresh water
constantly evaporates off the saltwater culture causing the salinity of the culture to increase. The top-off
system we implemented uses a 55 gallon freshwater container connected to a buoy in our culture tub.
When the desired water level drops the buoy drops and freshwater is released. The top-off system keeps
the salinity of our culture consistent and reduces required maintenance.
Once a week the culture was fed Kent Marine Pro Culture Part A and Part B. This nutrient recommended
that for every 20 gallons of algae, 10 milliliters of Part A and Part B were needed. For our 120 gallon
Figure 2.1.3: This top-off system provided
freshwater to our culture to reduce risk of salinity
shock. Algae nutrient was later added to the top-
off to reduce nutrient shock. The left outlet valve
leads directly to the culture and the center outlet
valve was used to flush the system.

18. culture, 60 milliliters of nutrient needed to be added once a week. To improve consistency and reduce risk
of culture shock, the nutrient was added to the top system. Every week 7 gallons of water would
evaporate from the culture which the top-off system replenished. Since our top-off system could hold
about 55 gallons of water, or 8 weeks of evaporated water, we added 8 weeks of nutrient supply.
A cell count was performed weekly to observe the algae’s cell concentration. Fifteen microliters of algae
is pipetted onto hemocytometer slide under a light microscope and using 40x objective, the cells are
counted using the slides grid. This gave our team an accurate representation of the cell concentration and
overall health of the culture.
Figure: 2.1.4: Kent Pro-Culture part A and B was
used to provide nutrients for our culture. The
culture was fed 10 milliliters of both parts for
every 20 gallons of algae. Part A contains
minerals such as iron and Part B contains macro
nutrients such as nitrate.
Figure 2.1.5: A cell count conducted on a
hemocytometer slide is shown above. The 4 by 4
grid was used to determine cell density. The
average of 5 different 4 by 4 grids was taken to
more accurately determine cell density.

19. Once the culture was grown to proper volume and cell concentration, processing could occur. To safely
operate the equipment and handle n-Hexane, Standard Operating Procedures were created. These
procedures were created to provide a clear step-by-step process of how our team would retrieve algae oil.
Familiarization with the SOP for this process is mandatory and ensures safety, accurate measurements,
and reproducible results. The S.O.P. procedures were conducted for JMU’s safety marshal and received
approval.
2.2 Harvesting
Previous biofuel teams under the advisement of Dr. Christopher Bachmann used flocculation harvesting
to concentrate algae cells then dewater them for oil extraction. These methods as well as many other
methods, are time consuming and energy intensive. This bottleneck has restricted algae oil from
becoming a successful alternative thus far and before algae oil can be considered as the replacement for
fossil fuels, the harvesting process must produce profitable energy, on a large scale, at a fast rate.
Emulsification was considered as a possible alternative harvesting method that would avoid the need to
concentrate cells and dewater them all together. The process of emulsification mixes two or more liquids
that are normally unmixable or unbendable, such as oil and water. For our harvesting process we used
emulsification to mix algae and hexane. Hexane is a powerful non-polar solvent that is commonly used by
the industrial sector to extract plant oils. We hypothesized that emulsifying the algae in the presence of
Hexane would effectively shear the cell walls, releasing the oil. Once released, the oil would bind to the
hexane and separate itself from other by-products, such as salt water and soluble molecules.
We were able to obtain and emulsifier from Wholesome Energy and Nonox Ltd. With this device we
were able to confirm our hypothesis and the emulsification of algae was a success because; Cells were
being collected and harvested simultaneously, the algae cells were quickly sheared in the presence of
hexane, this emulsification device could be incorporated into a flow-through process. The system was
fully scalable, and most importantly the process did not require energy intensive harvesting steps.

20. We decided that for each harvest that 15 liters of algae would be emulsified with 1 liter of hexane at 50
psi. This pressure was necessary to properly shear cell walls but also maintain reasonable flow rates.
After much trial and error we added a flow control valve to in order adjust the hexane input so we could
maintain the 15:1 ratio previously mentioned.
To begin the harvesting process each participant must be properly equipped with adequate safety gear. A
cell count is conducted on a hemocytometer slide to record the algae’s concentration of that day. The
observed cell concentration must be recorded in lab notebook for future reference. The fume hood
window needs to be opened and held it in place with the bungee cord located above. The fume hood timer
needs to be activated and kept track of or it will shut off.
Next, the desired amount of algae culture must be collected from the culture tub. The top-off system
needs to be cut off by turning the lever below the top off system to be perpendicular to the tubing. This
will restrict excess amounts of freshwater from entering the tub, potentially causing a salinity shock. The
tub must be sized up and replenished before the top-off valve can be reopened.
Align the harvesting pump on the cart in front of the fume hood window and prepare the pump by wiping
the tubes with a rag and plugging it into the power strip. Before running anything, it is imperative that all
the tubes are correctly placed. The two upper valves on the pump are the inlet valves, the valve all the
way to the left on the bottom is the outlet valve, and the valve on the right on the bottom right is not used
in these procedures.
Figure 2.2.1: This emulsifier obtained from Wholesome Energy
and Nonox Ltd was used to harvest our algae culture.

21. Of the two inlet valves, the valve in the middle with the flow rate dial is the hexane inlet, and the valve on
the right is the algae inlet. One the tube on each of the used valves is for priming. The pump must have a
substance to pull on or else the machinery will be damaged. To prevent damage and ensuring a constant
flow in the system, the pump must be primed. We primed our the harvester using freshwater and a funnel.
The primer tube was raised and freshwater primer was poured into the funnel connecting to the tube.
Once the tube is filled with primer, the pump is turned on until the gear pump creates a vacuum and pulls
water throughout the pump.
While the primer is running through the pump, the emulsifier chamber needed to be adjusted to a pressure
of 50 psi. This is done by using a flat head screwdriver to adjust pressure up or down. As mentioned
before, this pressure properly emulsifies cells at reasonable flow rates.
Figure 2.2.2: This schematic represents our emulsifier. Algae culture
and n-Hexane are drawn in by the pump and emulsify in the
emulsification chamber. The output is collected in a carboy that is
placed inside our fume hood.

22. Next, the n-Hexane flow rate must be adjusted. A total flow rate of the harvesting system with two inputs
was calculated using varying pressures. Table 2.2.4 below expresses the change in flow rates as the
pressure of the pump increased and decreased.
As the pressure increased, the total flow rate of the harvester decreased as expected. From this table, a
pressure of 50 psi was selected to continue working with throughout the duration of our project. A flow
rate of the n-Hexane input needed to be established as well. From the flow rates obtained from 50 psi, the
flow rate of the n-Hexane input and the total amount of time each run would take was calculated. Table
2.2.5 displays these results below.
Figure 2.2.3: To achieve emulsification, a pressure of
50 psi must be reached before the emulsification tube.
The pressure was adjusted by turning a knob with
screwdriver located on the tube, which either
restricted or permitted flow.
Table 2.2.4: The established flow rates at each tested pressure is
represented here. 50 psi was used for the continuation of this project
because at this rate the flow rate was manageable, the energy costs were
affordable, and the cell lysis was still effective.

23. After the flow rates were established with rigor, effective harvesting was ready to take action. Each full
trial consisted of three runs simply to have a higher yield of algae crude oil for measuring purposes.
Before the harvester is activated, a Kilo-Watt Energy Reader is attached to the plug to calculate the
wattage the pump requires. Though only 8 effective runs were conducted with the harvester,we were able
to gather 10 runs of data with the energy reader. Table 2.2.6 below shows the run data and the average
energy consumed daily, per run, and the cost per run of the harvesting pump.
Table 2.2.5: The total run time as well as the flow rate of
the n-Hexane input is displayed. Each 50 mL of n-Hexane
should be consumed during the process should take
approximately 19.43 seconds to maintain flow rates.
Table 2.2.6: Each of the energy readings for the runs
conducted are displayed. The associated costs were
calculated as well from results of the Kilowatt Energy
Reader.

24. Once the flow rate is achieved and the energy reader is connected, the system is now ready to harvest.
First, the n-Hexane needs to be safely transported to the fume hood using protective gear. A 1000
milliliter beaker is filled with the desired n-Hexane amount inside the fume hood, then the hexane
container is returned to the flammable cabinet. Once the system is turned on, a timer should started,
recording the total harvesting run time. Our harvesting process used 1000 milliliters of n-Hexane with
15,000 millimeters which required 6 minutes and 48 seconds to run.
We continuously checked the flow rate of the n-Hexane, and the pressure of the pump. The harvesting
process ran its course until one or both of inputs depleted. If one input was depleted before the other, the
system was turned off and the remaining volume was recorded. Stop the timer the moment the system is
turned off and record the processing time. The KiloWatt reader energy data was then recorded.
The output tubes are then removed from the carboy and it was capped to reduce n-Hexane evaporation.
The output mix inside the carboy needs sits for at least 24 hours, allowing the n-Hexane to separate from
the intermediate and saltwater layer. Three of these runs are the equivalent to a single trial.
2.3 Separation of End Products
The objective of the centrifugation process is to separate n-Hexane and algae oil from the intermediate
layer. Amphipathic molecules found inside the intermediate layer trap amounts of n-Hexane and algae oil.
By using a centrifuge we can spin the intermediate layer down, separating the less dense n-Hexane from
the denser amphipathic molecules. The more n-Hexane we obtain, the more we can recycle, improving
the sustainability of the process.
To begin centrifugation each team member must be properly equipped with adequate safety gear. The
fume hood needs to be on and running before the carboy can be opened. The volume of each carboy is
recorded before removing their contents. A large 3,500 milliliter beaker was used to remove the bottom
layer. The bottom layer consisted of unprocessed cells and saltwater. This layer was removed from the
carboy and safely disposed of. The intermediate layer and n-Hexane are then poured into 1000 milliliter
beakers for more accurate measurement. To reduce n-Hexane evaporation, all 1000 milliliter beakers
were covered with plastic wrap.

25. The centrifugation system is outside of the fume hood, so the intermediate being centrifuged must be
poured into centrifugation tubes and capped. The centrifuge we used could only spin six, 15 milliliters
tubes at a time. Once the six tubes were filled to the 15 milliliter mark and capped, they were then placed
into the centrifuge and spun for four minutes. After four minutes, three distinct layers are present; the n-
Hexane/oil mixture at the top, a small emulsified intermediate layer, and a green saltwater algae layer. We
suspect that the intermediate layer contains minimal amounts of n-Hexane and oil which can never be
fully separated due to the lack of power our centrifuge provides.
Figure 2.3.1: Left - This carboy contains the output of a harvest. The transparent top layer contains
the emulsified n-Hexane and algae cells. The bottom green layer contains salt water, polar molecules,
and unprocessed algae cells. Right - The bottom layer is poured off and disposed of while the top layer
the emulsified top layer is collected into beakers for more accurate measurement. The right beaker
contains only emulsified output while the right beaker contains some saltwater byproduct.
Figure 2.3.2: Left - This centrifuge was used to further separate the emulsified output to
retrieve trapped n-Hexane and oil. Right - This test tube has been centrifuged, providing 3
distinct layers. The top layer is n-Hexane containing oil, the middle is amphipathic
molecules which trap n-Hexane and the bottom layer is saltwater by-product.

26. The top layer was then poured off into a beaker in the fume hood and later used in our reclamation
process. The intermediate layer had to be properly disposed of since it contained n-Hexane. This layer and
the bottom layer were poured into beaker in the fume hood and left until all n-Hexane was evaporated off
in. Once fully evaporated the remaining by-product could be safely disposed of. The final volume of n-
Hexane/oil mix was recorded and now reclamation can be conducted.
2.4 Algae Oil Purification and Solvent Reclamation
The idea of the reclamation system is to ultimately save costs, resources, and make the process as
sustainable as possible. In this process, the n-Hexane/oil mix that has been collected from the harvesting
and centrifuge process is poured into a distillery device. Our distillery device was created by Remy Biron,
a former algae capstone member. The oil is dissolved into the n-Hexane solvent and the reclamation
system separates the two. Water is heated to 90 degrees Celsius and pumped through tubes in the
distillery. This temperature is above the boiling point of n-Hexane but below that of oil. This allows the
n-Hexane to vaporize and rise to the condenser where it is collected back in its liquid phase. A more
purified oil mixture falls to the bottom of the device where it is collected and rerun through the distillery
to further purify it. All the reclaimed hexane can be recycled and reused for the harvesting process.
First, a 5 gallon bucket that contains a heating coil inside is filled with tap water and covered with a lid. A
variable transformer is plugged into the wall outlet to pull more voltage, heating the water to our desired
temperature. The temperature is measured with a glass thermometer that needs to be continually checked.
Once 90 degrees Celsius is reached plastic pump tubes were placed inside the bucket and the pump was
turned on. The condenser chamber requires ice water to be pumped through a copper coil. Roughly 2
gallons of water and 5 pounds of ice is mixed in bucket with a submersible pump. This pump is connected
to the copper condenser coil with plastic tubes and the outlet is recirculated into the bucket.
Figure 2.4.1: This reclamation device was created by a previous JMU ISAT student, Remy
Biron. It is used to distill n-Hexane off any retrieved algae oil. The device is pumped with
hot water on the right side and pumped with cold water on the left. The n-Hexane harvester
output is poured in, vaporizing any n-Hexane. The oil continues to fall downward as the n-
Hexane rises to the condenser.

27. When the hot and cold water begins circulating through the system, the n-Hexane/oil mix can be poured
in. A funnel is connected to tubing which leads to the miscella inlet. The funnel should be able to reach
into the fume hood so any n-Hexane fumes can be removed by the fume hood. Both the condenser and
evaporator valve should be fully closed when initially introducing the mix.
A 500 milliliter beaker is placed under the evaporating valve outlet and a 1000 milliliter is used to collect
condensed n-Hexane. The n-Hexane/oil mixture is slowly poured into the miscella funnel to allow the n-
Hexane to fully vaporize. The system can “burp” the n-Hexane back up the inlet if too much is added
quickly. Once the condenser valve is opened, recondensed n-Hexane will immediately start to drip out.
This valve needed to remain open during the addition of n-Hexane/oil mix in order for n-Hexane fumes to
pass by the condenser. When the condenser outlet stopped dripping, the valve was closed and collected n-
Hexane was placed into the fume hood. With the 500 milliliter beaker sitting under the evaporator valve,
the valve was opened and all contents were collected. Depending on the volume of collected purified oil,
a second reclaiming may be needed. If we collected a volume larger than 100 milliliters, our team would
re-reclaim this amount to further purify the oil and collect more n-Hexane.
All reclaimed n-Hexane was measured and recorded then combined and poured into a securable container
to be stored in the flammable safety cabinet. The bottom residuals collected we left in the fume hood
without a cover, so any remaining n-Hexane could evaporate off. Once n-Hexane is fully evaporated, oil
will be the only remaining factor. The three runs are combined to create a trial and all the amount of algal
oil is recorded.
2.5 Algae Oil Quantification
After all the procedures for harvesting, centrifuging and reclamation have been completed, the amount of
algae oil can be quantified. By allowing the remnants of the n-Hexane in the small beaker evaporate off in
the fume hood, algae oil is left as a result. To easily transfer this oil to a smaller tube for storage, the
Figure 2.4.2: Left - A beaker collects purified oil from the evaporator valve. Right - The
reclaimed purified hexane is shown on the left and the purified oil on the right. This is the result
from a single harvest run of 4 gallons.

28. beaker is heated on a hot plate slightly and once the oil is loose it can be scraped out. Meanwhile, the
instruments and storage tube were tested for uncertainty with 1 mL of water. A 15 mL tube was used
(smaller measureable tube is recommended but we did not have access to one), and an approximate
measuring uncertainty was gauged by adding and removing water in a series of measurements (5
microliters, 50 microliters, 75 microliters, 100 microliters, etc.). Whichever amount of measurement was
visibly different to the naked eye was used as the measurement uncertainty. For example, if a noticeable
difference between adding 5 microliters to the contents of 1 mL was visible, that was the uncertainty. This
was done for the yields and energy readings to understand that external factors like human error,
instrument calibration, and other factors can highly affect the precision of results. After all the data was
collected, the standard deviation was calculated for the results of the oil yields and for the associated cost
per run obtained by the Kilowatt Reader, which connects to the harvester and reads the amount of energy
the pump requires.
2.6 Determination of Energy Input vs. Output
As mentioned before, a Kilowatt Energy Reader is connected to the power outlet of the harvesting pump
to assess its wattage and the amount of energy it requires to be powered on. This device produces wattage
readings after the process is complete and that value is recorded. After each of the runs have obtained
energy readings, the standard deviation is then calculated.
The combined uncertainty, displayed as Equation 1 below, can then be used to quantify the uncertainty of
this measurement.
𝑪𝒐𝒎𝒃𝒊𝒏𝒆𝒅 𝑼𝒏𝒄𝒆𝒓𝒕𝒂𝒊𝒏𝒕𝒚 = √[
𝒀𝒊𝒆𝒍𝒅
𝑹𝒖𝒏
−𝟏
∗ 𝝈 𝑪𝒐𝒔𝒕]
𝟐
+ [−(
𝑪𝒐𝒔𝒕
𝑹𝒖𝒏
)(
𝒀𝒊𝒆𝒍𝒅
𝑹𝒖𝒏
)
−𝟐
𝝈 𝒚𝒊𝒆𝒍𝒅]
𝟐
(1)
Figure 2.6.1. - A P3 International Kilowatt
Energy Reader was used to determine our energy
input for the harvesting process.

29. The uncertainty of a measurement can be for the better or worse for a scenario, but it is very important to
include in error prone calculations. Once this was determined, it was applied to our oil yields to
understand that it is difficult to have exact precision in a cheap lab setting.
Along with the calculation of the combined uncertainty, an energy ratio was calculated as well to
understand if this process was efficient from an energy standpoint. It only makes sense to have a process
that produces energy require a smaller amount of energy input and have a larger amount of energy output.
This was done using Equation 2 displayed below.
𝐸𝑛𝑒𝑟𝑔𝑦 𝑅𝑎𝑡𝑖𝑜 =
𝐸𝑛𝑒𝑟𝑔𝑦 𝑅𝑒𝑎𝑑𝑖𝑛𝑔 𝑜𝑓 𝑃𝑢𝑚𝑝 (𝐽𝑜𝑢𝑙𝑒𝑠)
𝑂𝑖𝑙 𝑌𝑖𝑒𝑙 𝑑 𝑝𝑒𝑟 𝑟𝑢𝑛∗𝐴𝑙𝑔𝑎𝑒 𝑜𝑖𝑙 𝑒𝑛𝑒𝑟𝑔𝑦 𝑑𝑒𝑛𝑠𝑖𝑡𝑦(𝐽𝑜𝑢𝑙𝑒𝑠)
=
𝐸𝑛𝑒𝑟𝑔𝑦 𝑖𝑛𝑝𝑢𝑡(𝐽𝑜𝑢𝑙𝑒𝑠)
𝐸𝑛𝑒𝑟𝑔𝑦 𝑜𝑢𝑡𝑝𝑢𝑡 (𝐽𝑜𝑢𝑙𝑒𝑠)
(2)
For this model, the amount of oil yield per run must be quantified and the energy input from the harvester.
Since this is ratio, it is unit-less where the units on the top must match the units on the bottom to cancel
out. From previous projects, a bomb calorimeter test was performed on the algae oil and determined that
the energy density was 42 MJ/L. This value was then multiplied by the oil yields converted to liters to
obtain an energy measurement. This was done for each of the trials performed and an energy ratio was
presented in the final findings.
2.7 Mathematical Modeling of Theoretical Algae Oil Yields
The purpose of this report is to understand how algae biofuels can impact the decision to switch to a
cleaner more sustainable fuel source while still being able to meet the current demand for liquid fuel. To
understand the full potential algae microorganisms could have to contributing to the United States fuel
supply, a comparison had to be made against conventional biofuels made from soybeans and corn. Data
was gathered from reliable sources about the oil yielding per unit of area from both of the conventional
biofuels used as a comparison. The data gathered during this experiment was used to determine the oil
that can be yielded per unit area for this specific algae strain. Once the units correlated, a comparison is
made to see which fuel is most efficient in terms of land use, area required, harvesting rate, and energy
density per unit area.
2.8 Cost Analysis
The main component associated with the calculated costs was the amount of energy input the harvester
pump is required. This was the only parameter that dictated the cost throughout this experiment. Despite
there being other costs involved, in a real world application, it can be assumed that those costs would be
mitigated which is why they were not included. Costs that fall into this category includes the grow lights,
the centrifugation, the fume hood, and the reclaiming of n-Hexane. All of these would not be necessary in
a large scale setting located in the ocean. Once the energy reading was obtained in kWh, the current cost
of electricity in Harrisonburg, Virginia was used to obtain a total cost of usage for the pump. Then the
rate at which oil was yielded to see how long the pump would have to run for in order to obtain a gallon, a
barrel or a total U.S. demand of algae oil. Now the cost can be compared to current fuels sources and
other biodiesels.

30. 3.0 Results
As the United States is in search for a cleaner fuel alternative to oil usage due to environmental concerns
and energy security, this project was pursued with the objective to have an output of algae crude oil from
our novel harvesting pump as energy efficient as possible. To further optimize our process included
adjusting flow rates, adjusting the pressure of the system, understanding the energy costs as parameters
change, and quantifying the energy density of our oil output. The first results obtained were the flow rates
necessary to maintain the algae to hexane ratio of 15:1. This was already specified in a previous project
and was not tampered with during our experimentation. After the flow rates were adjusted as shown in the
Methodology sections, the energy readings were established and the process could then be applied in real
time.
With the dictated energy results, a cost for the algae oil output was generated. But first, a n-Hexane loss
was noted mainly from evaporation and throughout the system. Table 3.1 below shows an accumulation
of the n-Hexane input and output for all the runs, showing that on average only 40% of the total n-Hexane
put into the system is retrieved at the end of the oil extracting process.
The total findings from the 4 main trails are displayed below in Table 3.2, noting that each is only
yielding on average 40% of its total capabilities. For comparison, for each trial is calculated with a
theoretical return of n-Hexane of 100%. Trial 1 was obviously the best oil yielding trial that was
conducted as seen from the table. If the process was capable of retrieving 100% n-Hexane back, this
novel harvesting process would be energy efficient and borderline cost competitive.
Table 3.1: There was a noticeable n-Hexane loss throughout the
system. The losses were documented and are presented in this
table. The average loss of about 40% was used in further
calculations.

31. The average oil yield per trial varied greatly depending on the health and concentration of the algae pool
at the time of harvesting. As seen from the table above, the trials displayed had a range of oil yields
because of the algae health. Figure 3.1 below depicts the oil yields per trial along with the standard
deviation.
Table 3.2: The total run data for the duration of this project is presented above, as well as a projected
100% retrieval of n-Hexane. It is important to notice the data specifically for Trial 1 since this was the
highest oil yielding trial. As it is 40% efficient in reclaiming n-Hexane, the cost per gallon is at its
lowest and the energy ratio is almost less than 1. As it is 100% efficient in reclaiming n-Hexane, the
cost per gallon substantially drops and the energy ratio is less than 1, meaning it is an energy efficient
process.
Figure 3.1: Above is a graph representing the algae oil yields for each trial
conducted during the duration of this project. Each trial was a consolidation
of 3 runs through the harvester. Trials 1 and 4 had a healthy algae
concentration, while Trials 2 and 3 were the result of an algae die off. The
error bars represent the standard deviation of the data set.

32. Trial 1 was by far the best oil yield experienced in the short amount of lab time. Trials 2 and 3 suffered
based on reasons to discuss later in this report, but ultimately because of the culture health. An average oil
yield from all trials and the uncertainty of the measurement is displayed as Figure 3.2 below.
The average oil yield from all the trials was approximately 0.75 mL. The uncertainty of this has a rather
large range due the range in yielding data from each of the trials. With the different oil yields, each trial
experiences a difference in cost as well. Table 3.3 below is a sensitivity analysis of the amount of oil
output by the system to the total cost per gallon of algae oil.
As the yields of oil increase, the price per gallon of oil decreases. This is displayed in Figure 3.3, where
the graph steadily declines exponentially and plateaus. The cost to harvest for this data set was $0.24 per
full day of harvest.
Figure 3.2: This graph represents the average oil yields
for the sampled runs. The error bar represents the
calculated combined uncertainty, which takes into account
all the influence uncertain factors with measurements and
some human error.
Table 3.3: The sensitivity analysis shows how a slight change in oil yields highly affects the cost
per gallon. As the oil yields increase,the cost per gallon decreases. A standard energy cost of $0.24
per kWh was used.

33. Applying the data to real time, Table 3.4 below indicates the amount of algae culture the United States
would need if algae biofuels were to fuel the demand the year of 2015 experienced. For a comparison of
data, corn based ethanol and soybean based biodiesel was calculated as well.
Figure 3.3: The graph expresses the negative linear relationship that cost per gallon of algae crude
oil has with the algae crude oil yields. As the amount of yields increases, the cost per gallon
decreases.
Table 3.4: Application is a large aspect to any novel system. This table shows calculations of real
world applications of algae oil harvesting and its dominance over other types of biofuels, where it
requires less area of maintenance and has a continuous harvest. The main take away is that algae oil
harvesting requires a lot less area to harvest a larger amount of oil.

34. The biggest takeaway from this table is that algae requires minimal area for cultivation compared to other
alternative liquid fuels. The biggest contributing factor to this is the ability algae has to double every 48
hours. This creates an astounding advantage over crops like corn and soybeans that can only be harvested
once a year. As shown by the data, algae as a fuel source shows a huge promise to the future of biodiesel.
Other forms of biodiesel do not compare and this can largely be attributed to doubling rate algae
experiences.
4.0 Discussion
As stated previously, the need for an alternative fuel for energy security and the betterment of the
environment has experienced notable attention recently as global climate change becomes more prevalent.
With this, algae biofuels have shown promise with oils yields but has chronic issues with cultivation and
harvesting. The purpose of each of the experiments conducted was to optimize the novel harvesting
method to yield the highest algae oil percentage as possible. In doing so, the first stage required an
understanding of the harvester in terms of its harvesting speed at different pressures. As the pressure
increases, the harvesting speed of the system decreases. In other words, as pressure increased, the flow
rate of liquids circulating slows down. High pressure makes the pump work harder as well, which in turn
increases the energy the system requires. As the pressure was adjusted as seen in Table 2.2.4, a
standardized pressure was needed to consistently run the harvester on. 50 psi of pressure was selected to
continue working with because it allowed a slow enough flow rate to ensure emulsification, it was a
manageable speed for lab members to work with, the pressure wasn’t too high that our energy input costs
were expensive, the cell lysis was extremely effective and because the pump itself was not over stressed
at this level of pressure. These flow rates were established by using two inputs with a colored liquid
(algae or dyed water); once the output showed color after the system was running, a timer was stopped.
Now that an approximate flow rate was achieved for the algae input of our process, a n-Hexane flow rate
needed to be established. An algae to n-Hexane ratio of 15:1 needs to be maintained throughout the
process. This was a predetermined ratio established by previous experimental groups and was not
tampered with during this project. A control flow rate valve was installed onto the pump on the n-Hexane
input valve. For an effective 15:1 algae to n-Hexane ratio, with an algae speed at approximately 41.54
milliliters per second at 50 psi, the n-Hexane must flow at 2.57 milliliters per second. This was
maintained by checking the speed of consuming each 50 milliliters of n-Hexane which should take
approximately 19.43 seconds, giving the system a total run time of 6 minutes and 28 seconds shown in
Table 2.2.5.
With the flow rate data achieved, runs were harvested in sets of three. The three runs were consolidated
and considered one full trial. This was done for measuring purposes since each run yielded a very small
amount of algae crude oil, but when the volume was combined it was easier to denote a measurement.
One of the main objectives of this project was to calculate the energy ratio. To make this process energy
efficient, an energy ratio less than one is necessary, where a smaller amount of energy going into the
system and a larger amount coming out of the system. To quantify the amount of energy required for our
system, a Kilowatt energy reader was used which plugged into the harvester and read the total amount of
wattage the harvester required. The average wattage each run, shown in Table 2.2.6, required was

35. approximately 2810.2 watts, with a standard deviation of 140.9 watts and a calculated combined
uncertainty of 314.367 watts. Despite the range of the data, the average was fairly close to the median,
allowing the data to be interpreted normally. Using an energy density value of 42 MJ/L from a bomb
calorimeter test conducted in a previous report, an energy ratio could now be calculated based on the
amount of algae crude oil yielded. Equation 2 in the Methodology section exhibits how the ratio was
obtained.
As the team continued working with the harvester under the established parameters, a comparison
between the input amount of n-Hexane and the output amount of n-Hexane was brought about. From this,
a substantial n-Hexane loss was discovered. On average, our system loses about 60% of the total n-
Hexane put into the system, where only 40% is obtained at the end of our process. Table 3.1 expresses the
exact percentage of losses each run experienced along with the calculated standard deviation, and average
value of the total losses. The losses of n-Hexane can largely be attributed to n-Hexane evaporation since
its volatility is rather high and to the fatty lipid layer in our harvesting output, as well as some to getting
caught up in the pump and reclamation system. In some procedures of this project, you can actually see
the n-Hexane evaporate while working with the substance. This can be seen during harvesting, when the
reclamation system drains the reclaimed n-Hexane, and when the output carboy is uncovered during the
harvesting process. The fatty lipid layer of the harvesting output has strong indication that n-Hexane is
still present in that layer. Previous projects before this one never experienced a fatty layer as large as seen
during this project. Usually the n-Hexane flows to the top of the output beaker since its density is much
lighter compared to algae, but throughout this project only a small portion of it floats to the top while the
remaining amount is caught in the lipid layer. The amount of n-Hexane that is caught in this layer is
unknown, but the smell of this layer suggests a large amount. To mitigate losses, centrifugation was
added to our procedures to gather as much n-Hexane as possible. The n-Hexane is important throughout
this process because its job is to trap oil molecules and hang on to them. If there are substantial n-Hexane
loss, there are also substantial oil losses, giving lower oil yields and a less efficient process. Despite the
efforts to centrifuge with a very low powered surplus 15 mL tube centrifuge, the n-Hexane was still not
fully retrieved.
Even with the noted losses, the system always extracted algae oil. Table 3.2 represents all of the trials and
the outputs associated. Trial 1 had an oil output of 1.75 mL, Trial 2 had 0.5 mL, Trial 3 had 0.5 mL, and
Trial 4 had 1.0 mL. Each oil output has an energy input, energy ratio, associated cost, and combined
uncertainty. It is important to note that this project did not really obtain a gallon let alone a barrel of algae
oil. The combined uncertainty was calculated to understand the fluctuation within the presented data,
knowing that not all of the measurements taken are not precise due to instrument calibration, human error,
and given assumptions. The combined uncertainty was calculated using Equation 1 from the
Methodology section.
Trial 1 was by far the best trial, yielding the largest amount of oil in comparison to all the trials. This was
the first three runs conducted, when the algae was its healthiest, most concentrated, and was provided all
the necessary nutrients to prosper. With 1.75 mL of algae oil extracted from an input of roughly 45 liters
of algae, an energy ratio was calculated to be around 1.72. Since this ratio is larger than one, the process
at this yielding rate is not energy efficient because more energy is being put into the system than the
system is providing in the end product. Basically, a larger amount of oil needs to be collected in order to

36. lower the energy ratio. Assuming only 40% of the total oil was collected due to n-Hexane losses, a
generated cost per gallon of $6.08 with a combined uncertainty of $0.28 was calculated for the oil
yielding rate in Trial 1. With the current gasoline cost per gallon at $1.95 in Harrisonburg, VA, our
process shows to not be economically feasible at this oil yielding rate. To compare a raw product to
another raw product, a cost per barrel of algae crude oil was calculated at $255.31 per barrel with a
combined uncertainty of $28.56. When compared to the current crude oil barrel cost at $40 per barrel, this
method is still not economically feasible.
Trials 2 and 3 can be grouped together because these were the result of the same issue and yielded the
same amount of oil. These runs were conducted during a time period when the algae strain used was not
health because of a bacterial infection, a low concentration of algae cells was present, and another algae
strain had begun to thrive in the culture. This can mostly be attributed to an issue with the automated top
off system that maintained the algae’s salinity when evaporation occurred. The top off system is
controlled by a buoy, so when there is evaporation, the buoy stretches down and releases dechlorinated
fresh water and nutrients. Fresh water is used in the top off system for the saltwater algae strain because
as the water evaporates from the algae culture, the salt remains, keeping the salinity relatively consistent
if freshwater is continuously added when needed. This top off system failed one day and released 15
gallons of fresh water into the saltwater system, shocking the culture and the result was a algae die off.
The algae strain that thrived was one that could survive in lower salinities, but this was not a high oil
yielding strain. It is thought that this contaminate algae strain was introduced to the culture by uncleaned
glassware. With 0.5 mL of algae oil extracted from an input of roughly 45 liters of algae, an energy ratio
was calculated to be around 6.02. Since this ratio is larger than one, the process at this yielding rate is not
energy efficient because more energy is being put into the system than the system is providing in the end
product. Basically, a larger amount of oil needs to be collected in order to lower the energy ratio.
Assuming only 40% of the total oil was collected due to n-Hexane losses, a generated cost per gallon of
$21.28 with a combined uncertainty of $2.38 was calculated for the oil yielding rate in Trials 2 and 3.
With the current gasoline cost per gallon at $1.95 in Harrisonburg, VA, our process shows to not be
economically feasible at this oil yielding rate. To compare a raw product to another raw product, a cost
per barrel of algae crude oil was calculated at $893.57 per barrel with a combined uncertainty of $99.96.
When compared to the current crude oil barrel cost at $40 per barrel, this method is still not economically
feasible.
Trial 4 the algae culture began to replenish itself with extensive care and extra nutrients after a couple of
months. The culture started to have a higher concentration of the algae strain with the higher oil yield and
was slowly beating the contaminate algae strain. With 1.0 mL of algae oil extracted from an input of
roughly 45 liters of algae, an energy ratio was calculated to be around 3.01. Since this ratio is larger than
one, the process at this yielding rate is not energy efficient because more energy is being put into the
system than the system is providing in the end product. Basically, a larger amount of oil needs to be
collected in order to lower the energy ratio. Assuming only 40% of the total oil was collected due to n-
Hexane losses, a generated cost per gallon of $10.64 with a combined uncertainty of $1.19 was calculated
for the oil yielding rate in Trial 1. With the current gasoline cost per gallon at $1.95 in Harrisonburg, VA,
our process shows to not be economically feasible at this oil yielding rate. To compare a raw product to
another raw product, a cost per barrel of algae crude oil was calculated at $446.79 per barrel with a

37. combined uncertainty of $49.98. When compared to the current crude oil barrel cost at $40 per barrel, this
method is still not economically feasible.
Knowing that all of the trials did not produce and energy efficient ratio and the price range was still high,
the n-Hexane losses resurfaced in importance. 60% of the total n-Hexane put into the process is still
missing. So, a 100% return of n-Hexane was calculated for each oil yielding rate for each trial. This was
not actually obtained throughout this project’s time frame. Trial 1, yielding 1.75 mL of oil at only 40%
return would have yielded 4.37 mL of oil if there was a 100% return of n-Hexane. Not only is 4.37 mL of
oil a higher oil yield and much more intriguing, it also provides an energy ratio of 0.69, which is less than
one meaning that more energy is being produced than is being used to produce the oil. The cost per gallon
calculated was $2.43 with a combined uncertainty of $0.28, and a cost per barrel at $102.22 and a
combined uncertainty of $11.80. If we were to achieve 100% return of the n-Hexane, the end product of
oil would be a larger volume, provide an energy efficient process, and be almost cost competitive due to
the fluctuations in the current oil market.
Trials 2 and 3, yielding 0.5 mL of oil at only 40% return would have yielded 1.25 mL of oil if there was a
100% return of n-Hexane. Not only is 1.25 mL of oil a higher oil yield and much more intriguing, it also
provides an energy ratio of 2.41, which is substantially less than the previous energy ratio of 6.02. The
cost per gallon calculated was $8.52 with a combined uncertainty of $1.28, and a cost per barrel at
$357.77 and a combined uncertainty of $53.68. If we were to achieve 100% return of the n-Hexane, the
end product of oil would be a larger volume, but at this oil yielding rate the process would still not be
energy efficient and not cost competitive.
Trial 4, yielding 1.0 mL of oil at only 40% return would have yielded 2.50 mL of oil if there was a 100%
return of n-Hexane. Not only is 2.50 mL of oil a higher oil yield and much more intriguing, it also
provides an energy ratio of 1.21, which is almost but not quite energy efficient, but it is less than the
previous energy ratio of 3.01. The cost per gallon calculated was $4.26 with a combined uncertainty of
$0.52, and a cost per barrel at $178.89 and a combined uncertainty of $21.92. If we were to achieve 100%
return of the n-Hexane, the end product of oil would be a larger volume, but at this oil yielding rate the
process would still not be energy efficient and not cost competitive.
From the presented data, energy input versus energy output is very depended on the oil yields from each
of the trials. As the oil yields increases, the energy ratio decreases making the process energy efficient.
The process needs to be efficient because if there is more energy going into the system, consumption
increase as does cost. For this process to be feasible, the costs must be low to be somewhat competitive.
The energy ratio is directly related to oil yields, and algae concentration highly impacts the amount of oil
yielded. The more concentrated the cells, the more oil yielded; the more oil yielded, the more energy
efficient and cost efficient the process is.
Using the graphs displayed as Figure 3.1 and 3.2 in the Results section, a visual is provided for how much
the oil yields differed and decreased from the salinity shock. This was a major setback our system
experienced that will be explain in greater detail later on. The average oil yield suffered mainly due to
Trials 2 and 3. But looking back at Table 3.2, notice how sensitive the cost and energy ratio is to just a
milliliters of a difference in algae oil output. Table 3.3 is a brief sensitivity analysis of algae oil yields vs.

38. cost per gallon of algae crude oil. Not only does this show how important each milliliter of oil output is, it
also shows how important it is to understand the losses throughout this system. The system is highly
effective, but there needs to be more efficient ways to obtain as much of the n-Hexane put into the system
as possible. Either through a new and powerful centrifuge or testing new algae strains that would not
produce a large fatty lipid layer. Figure 3.3 portrays the negative linear relationship the cost experiences
as oil yields increases at a flat rate cost per harvest of $0.24 per day.
Taking a step back from the fine details of the data, a statistic provided by the EIA showed that the United
States consumed 19.4 million barrels of petroleum in the year 2015. Assuming that the algae crude oil
could be substituted directly in the place of petroleum, a hypothetical scenario was calculated and is
shown in Table 3.4. Using the best oil yielding rate from Trial 1, where 45 liters of algae harvests 1.75mL
of algae crude oil, and the harvester’s actual 40% yielding efficiency, the algae culture size needed to
produce 19.4 million barrels of crude oil is approximately 62 trillion gallons. This assumes a continuous
flow process of harvesting and an algae double rate of approximately 48 hours. This volume required
would require an area of space equal to approximately 98,000 square miles of land, which is equivalent to
about two full states of Virginia. If the novel system was perfect and had a 100% yielding efficiency, an
area less than the one state of Virginia of a culture size would be needed to sustain the petroleum demand
in 2015. With that being said, it is important to note the area needed is equal to that of Virginia, but this
process would prosper off-shore in portions of the ocean that have no life. In comparison, if another
alternative biofuel source were to attempt to fulfill the demand of 2015, like corn based ethanol, an area
equivalent to about 33 states of Virginia would be required. Likewise, if it were soybean based biofuels,
an area equivalent to about 217 states of Virginia would be required. As stated, this data truly exhibits the
potential and the promise algae has on future biofuel production. With its higher oil content and doubling
rate, algae could sustain the U.S. without disrupting the global food supply or causing a massive change
the current infrastructure in place.
4.1 Unintended Consequences
In this project, setbacks were experienced due to a salinity shock leading to a massive die off of
Nannochloropsis and a subsequent bacterial bloom. Due to the change in the salinity of the algae tub a
contaminant algae strand was able to thrive under the new conditions. Once run through the harvester, the
bacteria’s lipid membrane re-encapsulated the hexane and made it unrecoverable for the current
technology we were working with. This resulted in a drop in a major drop in the oil yield. Contaminant
algae strains and salinity changes would be some issues needing further investigation before real world
implementation.
For real world implementation of this project offshore cultivation would be the most economically and
environmentally friendly. However, as with any new technology, there would need to be a further in
depth environmental study on the possible effects of growing algae in dead zones. With the ocean
currents and ocean storms, algae have the possibility of moving to an unplanned area. This could be
particularly detrimental if the algae were to float over any reefs and block out the sunlight. Dead zones
are also breeding grounds for whales and are intersected by Maritime trade routes so growing algae in
these areas has the possibility of interfering with these practices. Algae also grows in blooms naturally so

39. having the technology to harvest the algae oil could incentivize cleanup of harmful algal blooms but could
pose the challenge of over harvesting algae blooms that are beneficial and necessary to the environment.
Laws would need to be written on who was allowed to harvest algae and a deeper investigation would
need to be conducted on environmental impacts but as far as other fuel sources algae has far more benefits
than negative consequences.
5.0 Conclusion
The objective of this project was to provoke the extraction of algae biofuels and implement its use in the
current fuel supply, ultimately because the environment is suffering from the pollution of current fuel
sources. Through this project two main roadblocks mentioned by the DOE’s 2010 National Algal
Biofuels Technology Roadmap were focused on to improve the harvesting method. As these roadblocks
were noted, it was sought to overcome them. Throughout the extensive research and efforts during this
project, it can be concluded that this novel process works, there is a consistent yield of algae oil, and the
end algae oil product fits the current infrastructure. Algae biofuels in theory is the perfect fit to replace
heavy polluting fuel sources like crude oil because there is no need for remodeling the current
infrastructure. By making improvements to both the system and the culture, the oil yield can be increased
to a point that makes it more competitive on the market. Despite the findings from this novel harvesting
method, there are still challenges to overcome. Some include the unknowns involved with large scale
cultivation and large scale harvesting. Algae as a biofuel contributes as a positive environmental impact
giving it a promising future. When it becomes more of a reality is when people make a conscious effort of
realizing the current situation people live in and take action to improve it.
6.0 Current and Future Direction of Research
A top priority for developed and developing nations has been to mitigate carbon dioxide emissions and
attack other environmental concerns contributing to global climate change, along with securing the
current energy crisis impairing sources of energy for future generations [44]
. With the growing energy
demand of the growing population, a quest for sustainable solutions at a low cost has brought about the
idea to utilize biomass as a transportation fuel [44]
. This option is readily available and does not require
additional production costs [44]
. Biomass includes naturally produced substances like algae, plants, and
vegetables that are living or recently living, all of which are abundant in the United States. With thermal
processing, or lipid transesterification to alkanes and biodiesel, blending the biomass byproduct with
conventional diesel is at a low cost and tailored to the current infrastructure [44]
. Not only would
reductions occur in the total amount of crude oil use, but sustaining fuel supplies would be established
until a more stable energy supply was achieved. Recent trials have even indicated that the energy quotient
for catalytic alkane production from biomass is twice that of fermentation routes to ethanol [44]
.
Incorporating biodiesel into the transportation sector would create a more efficient energy use from its
characteristics like its higher flash point, low sulfur concentrations and better lubrication efficiencies [45]
.
Carbon deposition is also decreased significantly when biodiesel is effectively mixed with petroleum
diesel [45]
. The process of transesterification has been the most commonly used method for the production
of vegetable oil and algal oil tied with alcohol in the presence of an acid or base catalyst. Ultrasonic