This document summarizes a student project analyzing the beer fermentation process. The students produced a blonde ale based on a chosen recipe and analyzed the process, environmental impact, and economics. Key findings include: 1) The produced beer met the targets for alcohol by volume and final gravity, indicating successful fermentation, but was darker than specified. 2) An environmental analysis found the students' process used more water and energy than industry standards. 3) An economic analysis calculated costs of raw materials, utilities, and proposed process improvements to reduce water and energy usage.

1. Beer Fermentation Process, Economic, and
Environmental Analysis
Prepared by: Hoang, Frank
Group: TR2, Team members: Anthony Achacoso, Ken Lim, Sai Sanigepalli
Email: fhoang7@berkeley.edu
Instructors: Dr. Landry and Prof. Landry
Date: 12/01/2016

2. 1
ABSTRACT
The objective of the fermentation project was to produce a drinkable beer based on a chosen recipe
and analyze the process, environmental impact, and economics behind the production of the beer.
We analyzed the thermodynamics of the process by collecting and analyzing temperature data
surrounding the preparation of our wort. We found that our heat exchanger model does not
adequately model the wort thermal behavior as the slopes of the temperature profiles are different
resulting in differing cooling times. While the wort was fermenting, we attempted to track the time
evolution of the beer fermentation but was unable to do so due to equipment malfunction. After
the beer was finished, we extracted samples to quantify beer qualities such as color (SRM),
bitterness (IBU), alcohol content (ABV), and sugar content (FG) and compared it recipe
specifications and found that we met the ABV and FG targets. Our environmental and economic
analysis of our process evaluated at the batch level (2.5 gallons) as well as at the craft brewery
production level (186 million gallons) allowed us to conclude the environmental and economic
benefit of making brewing process improvements and recommend that process improvements be
implemented in future beer production.
INTRODUCTION
For many amateur brewers, beer brewing is an art that relies on a general, non-technical
understanding of how to make a tasty beverage. However, in this fermentation project, we want to
identify and apply scientific theory which can help us understand how to produce beer that meets
our objectives. We decided to make a blonde ale based on Brulosophy’s recipe (see Appendix A).
Our objectives include beer qualities such as desired beer color, alcohol content, bitterness, and
sugar content provided to us by the recipe. We can measure our success at carrying out the recipe
by observing how close we are to meeting the recipe’s beer specifications with our final beer
product.
We can quantify the beer qualities by utilizing designed lab procedures rooted in scientific theory
(see Appendix B for measurement equations). Beer color, quantified as the Standard Reference
Method (SRM), is measured by observing the absorbance of the beer through a spectrophotometer
at a wavelength of 430nm and scaling it using a general form of the Beer-Lambert law which
converts the absorbance into SRM.1
Each beer coloring is associated with a range of SRM values,
with the range being set by how color was defined numerically in the Lovibond system. Bitterness
is measured through a liquid-liquid separation that pulls iso-humulone, the main chemical
compound responsible for beer bitterness, from the beer.2
Alcohol content is quantified using gas
chromatography which separates and quantifies ethanol in the beer by taking advantage of how
ethanol interacts with the carrier gas with respect to other compounds present in the beer.3
Final
gravity, the specific gravity measurement of the beer, quantifies how successfully fermentation
converted the sugars in the wort, a liquid solution that becomes beer after fermentation, to alcohol
in the beer.4
Specific gravity measures the amount of dissolved compounds in water and therefore,
this physical property can be used to describe the amount of dissolved sugars in beer.
The chemical thermodynamics and kinetics theory relevant to fermentation can be applied to
understand why our produced beer could deviate from beer recipe specifications. Thermodynamics
can be applied to analyze the first stage of our brewing process, the boiling and cooling of our
wort. Errors and deviations during this stage of brewing influenced changes in beer color,

3. 2
bitterness, and product yield from the ingredients. We utilize the analytical Kern model which is
an applied energy balance that can be adjusted to model the wort thermal behavior.
𝜌 𝐻 𝑉𝐻 𝐶 𝑃𝐻
𝑑𝑇 𝐻
𝑑𝑡
= −𝑈1 𝐴 𝐶∆𝑇𝐿𝑀 − 𝑈2 𝐴 𝑝(𝑇 𝐻 − 𝑇𝑎𝑚𝑏) (1)
where ρH represents the density of the wort, VH the volume of the wort, CPH the heat capacity of
the wort, U refer to the overall heat transfer coefficient, A refers to the area of heat transfer, and
the ∆𝑇𝐿𝑀 represents the log mean temperature difference between the coolant and wort
temperatures. The second temperature difference (𝑇 𝐻 − 𝑇𝑎𝑚𝑏) points to the temperature
difference between wort and air. We are applying this model to simulate thermal behavior of our
version of the stirred batch reactor, the pot in which the wort is prepared, pictured in the below
figure.
Figure 1: The wort comprises of water, hops, malt, and yeast and is cooked in a stainless-steel pot with a
stir bar.
Heat transfer through convection and conduction are considered in the Kern model in the definition
of the overall heat transfer coefficients, U1 and U2, which describe the heat transfer behavior of the
heat exchanger used to cool the wort and the heat transfer of the wort to surrounding air
respectively. In order to understand what is happening during the second stage of beer brewing,
the fermentation, we apply transient mass balances on species of interest which are yeast cells,
substrate (sugar), alcohol.4
We expect our fermentation to conclude when the yeast consumes all
the fermentable substrate.
METHODS
We began our beer brewing by making the wort, the substance that will ferment into beer, by
adding water, hops, and malt in a stainless-steel pot. The wort must be heated in order to extract
flavoring from the hops and sugars from the malt and subsequently cooled with cold water (21ºC)
to suppress biological growth that could compete with the beer yeast that will be pitched in prior
to fermentation. Wort and coolant temperature data was collected through three thermocouples
(one in the wort, one in the water coolant stream at the inlet, and one in the water coolant stream
outlet). Wort temperature was collected to monitor temperature to ensure that the wort is heated,
cooled, or held steady at the appropriate temperatures as well as quantify heating and cooling times
to develop models for future process optimization. Coolant temperature data was collected for
inclusion in model development as well. Fermentation process behavior was monitored by
collecting initial and final measurements of the specific gravity through use of a hydrometer, using
gas chromatography to analyze ethanol introduced, and a spectrophotometer to measure yeast cell
production. In addition, carbon dioxide production time behavior data was collected from a
previous brewing lab group in order to estimate fermentation time.
Beer specification measurements were made by taking samples of the produced beer and using
Tambient = 22°C
Hops
Sugars Yeast

4. 3
analytical methods performed in literature.1,2,4,5
SRM measurement takes advantage of how the
beer will absorb a 430nm wavelength differently based on the beer’s color. 430nm is the
wavelength chosen to produce numerical values that quantify color similarly to the Lovibond
coloring system. Alcohol by volume (ABV) was measured using gas chromatography which takes
advantage of how quickly the solutes in the beer can pass through a carrier gas. Solutes with lower
boiling points pass through the carrier gas faster as they spend less time in liquid form when the
entire sample is vaporized. International Bittering Units (IBU) measurement relies on the
extraction of iso-humulone from beer by inducing a more polar environment in the beer sample
with an acid and then adding in a nonpolar medium (iso-octane) into which the iso-humulone will
prefer to move to.
In order to identify process improvements to be implemented in future batches, we perform an
environmental analysis of our beer production process. The analysis looks at how much water and
energy is used in each step of the process. We also proposed process improvements and estimated
how much water and energy could be saved if the improvements were implemented (for a detailed
layout of the environmental analysis, see Appendix C and D). Lastly, we compared our water usage
ratio, energy usage ratio, and emissions with industry usage ratios and emissions (see Appendix E
and F).
An economic analysis is performed in order to see how much money can be saved by implementing
proposed process improvements. Economic considerations covered the cost of raw ingredients,
utilities, and water with total costs being tabulated to project a six-pack cost as well as total annual
costs associated with scaling the beer production process to a craft brewery capacity (186 million
gallons of beer annually). We also analyzed the costs associated with the proposed process
improvements by calculating the monetary savings associated with energy and water conservation.
For the complete economic calculations, see Appendix G.
RESULTS AND DISCUSSION
Producing a beer that looks and tastes like the brew recipe is a key indicator of successful beer
brewing. In the table below, we have tabulated the important beer specifications.
Table 1: The chosen beer specifications provided by the recipe compared against experimentally
measured beer specifications of the produced beer.
Beer Specification Recipe Value Produced Beer Value
Standard Reference Method
(SRM)
4 12.4±0.2
Alcohol by Volume (ABV) 4.7%±0.3% 4.92%±0.05%
Final Gravity (FG) 1.009 1.012±.005
International Bitterness Unit
(IBU)
20 55.6±8.1
Through error propagation of final gravity measurement and accounting for the fact that reported
ABV values can fluctuate within 0.3% as permissible by law, we produced a beer that meets both
ABV and FG specifications.6
By meeting ABV and FG targets, our fermentation process can be
deemed as successful for converting the fermentable sugars in our wort into the appropriate ethanol
content. However, we were unable to hit the target SRM and IBU values. Beer color, quantified
by SRM, is influenced by wort boiling time, which we doubled, in an attempt to reduce the bittering

5. 4
effects of adding in more hops than the recipe called for.7
More boiling time results in a darker
color due to caramelization, a process in which the sugars in the beer decompose after prolonged
heat exposure.8
We also did not meet the IBU specification, a fact that we also attribute to the
addition of extra hops. IBU measures the iso-humulone content in the beer. IBUs will increase
with the amount of hops added into the wort as hops contain humulone, which is isomerized into
iso-humulone through the boil.
In an effort to optimize brewing conditions, we constructed models to simulate the heating and
fermentation time behavior of our brewing process. However, we find that our actual process
behavior differs from what our models predicted. We are unable to compare our fermentation
model with our actual fermentation behavior due to a lack of CO2 data, but we do not expect the
model to work well because the model made two incorrect assumptions, one being that the yeast
cells do not die and the other being that the yield coefficients remain constant over time. As the
yeast population fluctuates, we cannot assume that the yield coefficients can be constant as the
yeast will utilize substrate and produce ethanol at varying rates. Our heat model was also incorrect
because it did not account for the lack of mixing that occurs in our wort due to the addition of
viscous malt liquid extract and hops. We expect lesser mixing to result in less heat transfer as heat
convection relies on the flow velocity of the wort. We want to adjust our model’s (equation 1)
overall heat transfer coefficients to reflect the decrease in heat transfer. On the figures below, we
plotted our unadjusted model coolant temperatures with the experimental coolant temperatures.
The fit was significantly better when we adjusted the overall heat transfer coefficients (U1 and U2).
Another way of analyzing how to optimize our brewing process is to perform an environmental
analysis. We estimated how much water and energy we used in each step of our brewing process
(see Appendix C and D respectively for detailed considerations). We suggest process
improvements to amend the brewing steps that consumed the most water and energy. Wort cooling
with water as the coolant was the most water consuming brewing step (30 gallons per batch of
beer) since we directed the used coolant water into the sink. We propose a recycling system to
recycle the coolant water and use ambient air to cool the used coolant water (see Appendix C,
Coolant Water Recycle). The kegging of the beer consumes the most energy (10 kWh per batch)
as the forced carbonation and refrigeration occurs over a period of 2 days. We propose filling the
Figure 2a: Coolant temperature versus time
elapsed with unadjusted U1 (2.00 ∗ 103 𝑊
𝑚2 𝐾
)
and U2 (48.2
𝑊
𝑚2 𝐾
).
Figure 2b: Coolant temperature versus time
elapsed with lowered U1 (440
𝑊
𝑚2 𝐾
) and U2
(45.2
𝑊
𝑚2 𝐾
).

6. 5
kegerator’s capacity to an estimated 3 batches as the power consumption will be constant
regardless of whether one batch or three batches are kegged at a time. Other suggested process
improvements can be found in Appendix C and D and a comparison of our beer production energy
usage, water usage, and emissions compared to other breweries’ can be found in Appendix E.
Table 2: Suggested process improvements and practices with water/energy reductions, emissions
reductions, and economic savings if beer production was scaled up to a small craft brewery’s production
(186 million gallons).
Process Improvement Annual Water [gal] or
Energy [MWh] Saved
Emissions
Conserved[lbCO2-
eq]
Annual Economic
Savings [$]
Coolant Water Recycling 2.23 ∗ 109
gal Not applicable 4.46 ∗ 105
Collect 2 batches’
temperature data per
computer use
1.86 ∗ 104
MWh 1.21 ∗ 107
2.40 ∗ 106
Keg 3 batches per
kegging
1.93 ∗ 105
MWh 1.26 ∗ 108
2.51 ∗ 107
In Table 2, we scale up the water and energy savings to match the annual production of a small
craft brewery in order to better express the environmental impact and economic benefit of
implementing the process improvements. We find that what could be seen as a small
improvement in three brewing steps can have large economic and environmental impact when
scaled to the craft brewery production level. We calculated the costs associated with the current
brewing process (ingredients, water, energy) and compared it with the reduced costs of our beer
brewing if the process improvements are implemented (see Appendix E). By making minor
adjustments to three brewing steps, we can save sizable amounts of water and energy and even
pocket annual savings of more than $28 million if we were operating our beer production on a
craft brewery scale. By coupling the environmental and economic analysis, we see that being
environmentally conservative can pay great financial dividends for our beer brewing production.
CONCLUSIONS & RECOMMENDATIONS
Developing a general model to simulate beer brewing processes is difficult due to the variation of
ingredients that are used. The underlying assumptions in the simple models we developed break
quickly in the brewing process (yeast cells do not die, constant yield coefficients) as well as the
variation in yeast species and substrate used in different brew recipes. We recommend that general
models be developed and then adjusted to reflect the process conditions of the brewing process of
interest. We also conclude that measuring our beer specifications and comparing them with recipe
specifications is a great way to analyze the success of our recipe execution. By identifying physical
reasons behind our discrepancies with the recipe, we develop more understanding of the beer
making process to make beer that better meets recipe targets in the future. Through our
environmental and economic analysis, we conclude that process improvements can have a positive
environmental and economic impact. Therefore, we recommend that all suggested process
improvements be implemented as they clearly benefit the environment (reducing emissions in the
order of millions of pounds of carbon dioxide) as well as they reduce production costs (annual
savings in the order of millions of dollars).

7. 6
REFERENCES
1. Blankemeir, R. The Spectrohotometer and Beer: A Love Story. The New Brewer. Aug 2013.
2. De Keukeleire, D. Fundamentals of Beer and Hop Chemistry. Quimica Nova. 2000. 23. 109-
110
3. UCLA Department of Chemistry. Gas Chromatography Theory. [Online]. 2016.
http://www.chem.ucla.edu/~bacher/General/30BL/gc/theory.html (accessed Nov 27, 2016).
4. Landry, A. Yeast Fermentation Kinetics Lab Manual. UC Berkeley, 2016.
5. Landry, A. Fermentation Project Lab Manual. UC Berkeley, 2016.
6. U.S. Government Publishing Office. Labeling and Advertising of Malt Beverages.
http://tinyurl.com/gsxtgex (accessed Dec 01, 2016).
7. Pierce, B. Boiling: Advanced Brewing. Brew Your Own. Sept 2007.
8. Harbison, M. Beer Sci: How Beer Gets Its Color. Popular Science. Dec 2012.
APPENDICES
Appendix A: Beer Recipe/Procedure
Ingredients
Golden light liquid malt extract (65 oz.)
Mashed white wheat malt (6.5 oz)
Carapils (2.2 oz)
Crystal malt grains (4.8 oz)
Magnum Hops (.13 oz)
Columbus hops (.13 oz)
Cascade hops (.13 oz)
Irish moss (1 oz)
WLP 029 White Labs German Kolsch Ale Yeast (1 packet)
1. Measure 3 gallons of water in carboy and mark this level on the carboy.
a. Prepare thermocouples in pot lid and heat exchanger coil lid.
b. Sanitize appropriate equipment (glass carboy, stopper, airlock, funnel, wine thief,
aluminum foil, heat exchanger).
c. Add 1.8 gallons of water to kettle.
1. Turn ON temperature data collection software.
2. Add steeping grains (Crystal 10/Carapils) to kettle before heating, suspend in kettle
without touching bottom. (Use spoon shaft laid across kettle to suspend sac).
3. Begin heating by plugging in electric immersion heater and turning on hot plate.
4. Once temperature reaches 65 °C, take out steeping grains and add milled malted grains
(wheat malt) to cheesecloth sac, and suspend in kettle without touching the bottom.
5. Turn off electric immersion heater, adjust hot plate temperature setpoint to keep water
temperature between 150-160 °F (65-70 °C). Maintain this temperature for 30 min
while stirring.

8. 7
6. After 30 minutes, remove the sac, and put electric immersion heater back in, and
continue heating until it boils. Sanitize spoon used to hang grains for mixing in next
step.
7. Once at a boil, turn off electric immersion heater. Add malt extract (Golden Liquid
Light Malt Extract). Stir vigorously with spoon or stir bar.
8. Once malt added, restart electric immersion heater and heat until boils.
9. When there are no more signs of a hot break, it is time to add the hops. Timescale:
a. At 0 min, add the Magnum/Warrior/Galena hops
b. At 35 min, add the first round of Cascade hops
c. At 45 min, add Irish moss
d. At 50 min, add the Columbus (Tomahawk) and the second round of Cascade hops
e. At 55 min, add the final round of cascade hops
10. Unplug the electric immersion heater. Turn off the heating plate!
11. Collect 1 mL of wort solution to inspect under microscope using hemocytometer. Make
note of the appearance of cells/microorganisms.
12. Begin cooling the kettle by using the 9-loop immersion heat exchanger. Set up heat
exchanger similar to IHX lab. Set flow rate to max (~7.58 L/min). Make sure heat
exchanger is sanitized.
13. Take pH measurements every 5 minutes with the pH meter.
14. Once cooling has finished, take out heat exchanger and place it in sanitizer solution to
avoid copper tube fouling. Export temperature-time data. Collect 1 mL of wort solution
to inspect again under hemocytometer.
15. Add in water until we reach 3 gallons total in the carboy.
a. Keep taking new OG measurements every half gallon or so to make sure we do not
overwater our beer solution.
16. Once at 3 gallons and/or OG is at appropriate, aerate wort by using a bubbler for air
available in the lab (8-10 ppm O2).
17. Collect 200 mL of carboy solution to use for biomass concentration measurements
(after fermentation). Don’t mix this solution.
18. Collect 10mL of carboy solution to use for OD calibration curve (before fermentation).
Vortex.
19. Measure ½ pack of yeast using analytical balance. Find proportions of yeast that must
be pitched into carboy and flask. Activate the yeast, following the instructions given on
the packet. Pitch the appropriate amounts into the carboy and flask. Seal the carboy and
flask with the stopper connected to the flowmeter. Seal the flask with aluminum foil.
Appendix B: Beer Measurements (SRM, IBU, ABV, FG) equations
SRM (Standard Reference Management):
 𝑆𝑅𝑀 = 12.7 ∗ 𝐷𝑖𝑙𝑢𝑡𝑖𝑜𝑛 𝐹𝑎𝑐𝑡𝑜𝑟 ∗ 𝐴430𝑛𝑚
 A430nm is the absorbance of the beer in response to 430nm light.
IBU (International Bittering Units):
 𝐼𝐵𝑈 = 50 ∗ 𝐴275𝑛𝑚
 50 is the dilution factor specifically used for iso-octane, the solvent we used for IBU
separation in this lab
ABV (Alcohol by Volume):

9. 8
 𝐴𝐵𝑉% = 144.7333 ∗ 𝐺𝐶 𝐴𝑟𝑒𝑎 𝑀𝑜𝑙𝑒 𝐹𝑟𝑎𝑐𝑡𝑖𝑜𝑛 + 0.0289
Final Gravity (Specific gravity of post fermented beer)
 𝑆𝐺 = 1 +
𝐾0 𝑐 𝑠
1−𝑆1 𝑐 𝑠
 Constants K0 and S1 will differ based on malt type (for dry malt extract, K0=0.3815 mL/g
and S1=0.1327 mL/g
Appendix C: Water Usage/Water-related process improvements
Water Usage Sources and Contributions
1. Wort Creation
3 gallons to start in the wort, ~0.75 gallon added at to wort at the end of wort prep
process
Total: 4 gallons of water ± .75 gallons
2. Water for sanitizing solutions
a. Wort creation day: 2 buckets x 4 gallons of water per sanitization solution = 8
gallons of water
b. Post-fermentation/kegging: 2 buckets x 4 gallons of water per sanitization
solution = 8 gallons of water
Total: 8 gallons of water ± 2 gallons
3. Water coolant usage
2
𝑔𝑎𝑙𝑙𝑜𝑛𝑠
𝑚𝑖𝑛𝑢𝑡𝑒
∗ 900 𝑠𝑒𝑐𝑜𝑛𝑑𝑠 ∗ 1
𝑚𝑖𝑛𝑢𝑡𝑒
60 𝑠𝑒𝑐𝑜𝑛𝑑𝑠
= 30 𝑔𝑎𝑙𝑙𝑜𝑛𝑠
Source of error: 5% margin of error for flow meter
Total: 30 gallons ± 1.5 gallons
4. Volume of water used in process/Volume of beer produced
Volume of beer: 2.5 gallons ± .25 gallons
Water use ratio (
𝑤𝑎𝑡𝑒𝑟 𝑢𝑠𝑒𝑑 𝑓𝑜𝑟 𝑝𝑟𝑜𝑐𝑒𝑠𝑠𝑖𝑛𝑔+𝑐𝑙𝑒𝑎𝑛𝑖𝑛𝑔
𝑣𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑏𝑒𝑒𝑟
) =
42 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 𝑜𝑓 𝑏𝑒𝑒𝑟
=
158.987𝐿
9.464𝐿
= 𝟏𝟔. 𝟖 ± . 𝟏
Process Improvements (Projected Water Savings)
1. Improve uncertainty in measuring out water for sanitizing solutions
1% error associated with each graduated cylinder measurement (13 made in order to
measure out 3 gallons)
4 gallons of water for sanitizing requires 16 1L graduated cylinder measurement (.64
gallons of error)
Savings: 2-.64 = 1.36 gallons more accurate per batch
2. Adopt a phosphoric acid based sanitizer (Star San) in lieu of iodine based sanitizer (Io
Star)
a. Using Star San, we can keep the sanitization solution made on the first day of
brewing (wort creation) and reuse when we clean/sanitize kegging and
carbonation equipment

10. 9
b. Star San can be kept over 3-4 weeks in solution while Iodine based solutions
cannot unless stored properly
i. Iodine breaks down to iodide in the presence of light as the light provides
enough energy for the iodine to break down in solution as the water will
reduce the iodine compound. Observe this as the colorful iodine degrades
to the colorless iodide version.
ii. Phosphoric acid is stable and breaks down in the presence of heat but we
typically keep our sanitization solutions at room temp so not a problem.
Savings: 4 gallons of water ± 2 gallons
3. Coolant water recycle
a. The idea here is to recycle the coolant water and let the air cool the heated water.
We must construct a large enough tank to store the water long enough for it to
cool back to room temperature.
b. Recycle the water stream into a second pot in order to heat up the wort and then
recycle through a storage water tank for additional cooling
c. Requires 121 gallons to recycle coolant water through the system (see calculation)
Coolant Water Recycle Stream Calculation
Equation: Energy Balance on the Storage Tank (Cooling Wort system)
Purpose: To quantify the volume of water needed to circulate through the system to ensure
adequate cooling for the hot coolant’s temperature to return to the colder temperature at which it
was introduced to the wort.
𝜌𝑐𝑜𝑜𝑙𝑎𝑛𝑡 𝑉𝑐𝑜𝑜𝑙𝑎𝑛𝑡 𝐶 𝑝
𝑑𝑇
𝑑𝑡
= 𝜌𝑐𝑜𝑜𝑙𝑎𝑛𝑡 ∗ 𝑄 𝑐𝑜𝑜𝑙𝑎𝑛𝑡,𝑖𝑛 ∗ 𝐶 𝑝 ∗ 𝑇𝑖𝑛 − 𝜌𝑐𝑜𝑜𝑙𝑎𝑛𝑡 ∗ 𝑄 𝑐𝑜𝑜𝑙𝑎𝑛𝑡,𝑜𝑢𝑡 ∗ 𝐶 𝑝 ∗ 𝑇𝑜𝑢𝑡
− ℎ 𝑐,𝑎𝑖𝑟 𝐴 𝑡𝑎𝑛𝑘(𝑇𝑖𝑛 − 𝑇𝑎𝑚𝑏𝑖𝑒𝑛𝑡)
Recycle Coolant
Storage Tank
Wort Pot
(Cooling)
Cold Coolant (20ºC)
Ambient Air =
22ºC
Wort Pot #2
(Heating)
Figure: Coolant water is heated by absorbing heat from the hot wort. Hot
coolant water can be recycled by using the heat from the heated coolant to heat
up another pot’s wort. Convective heat transfer through the air will cool the
coolant in the storage tank back to operating temperature (20°C)
Hot Coolant (23ºC)

11. 10
The left side of the equation defines the accumulation of energy in the system. Energy
accumulation is calculated by multiplying density of the coolant 𝜌𝑐𝑜𝑜𝑙𝑎𝑛𝑡[
𝑘𝑔
𝑚3
], coolant volume
𝑉𝑐𝑜𝑜𝑙𝑎𝑛𝑡[𝑚3
], coolant heat capacity 𝐶 𝑝[
𝑘𝐽
𝑘𝑔 𝐾 𝑠
], and temperature change
𝑑𝑇
𝑑𝑡
[
𝐾
𝑠
]. Energy input and
output comes from the moving coolant which comprises of coolant density, volumetric flow rate
𝑄 𝑐𝑜𝑜𝑙𝑎𝑛𝑡[
𝑚3
𝑠
], coolant heat capacity, and the temperature difference between the hot coolant inlet
stream and the outlet coolant stream. The cooling mechanism for the storage tank will be ambient
air so the convective heat transfer term is included and comprises of the convective heat transfer
coefficient of air, hc, the surface area over which the convection will occur, Atank, and the
temperature difference between the inlet coolant and the air. The exiting hot coolant temperature
is calculated by averaging the thermocouple collected coolant data (Tin).
1000
𝑘𝑔
𝑚3
∗ 𝑉𝑡𝑎𝑛𝑘 ∗
4.184 𝑘𝐽
𝑘𝑔 𝐾 𝑠
∗
. 0008𝐶
𝑠
= 1000
𝑘𝑔
𝑚3
∗ (1.26 ∗ 10−4
𝑚3
𝑠
) ∗
4.184 𝑘𝐽
𝑘𝑔 𝐾 𝑠
∗ 23𝐶 − 1000
𝑘𝑔
𝑚3
∗ (1.26 ∗ 10−4
𝑚3
𝑠
) ∗
4.184 𝑘𝐽
𝑘𝑔 𝐾 𝑠
∗ 20𝐶 − .0145
𝑘𝐽
𝑚2 𝐶
∗ 1𝑚2
∗ (1𝐶)
3.3472 ∗ 𝑉 = 1.58 − .0145
𝑽 =. 𝟒𝟔 𝒎 𝟑
= 𝟏𝟐𝟏 𝒈𝒂𝒍𝒍𝒐𝒏𝒔 of water needed to implement coolant recycling
4. Scaling up production volume: how many batches of beer need to be made to see return
on water savings from the recycle system?
a. 30 gallons of water used for wort cooling/2.5 gallons of beer = 12
b. Scaling up production volume by making 5 batches of beer
i. Dump coolant water (current): 150 gallons of water/12.5 gallons of beer=
12
ii. Recycle coolant water (Process improvement): 121 gallons of water/12.5
gallons of beer = 9.68
iii. This water use ratio only decreases as you increase # of batches as number
of gallons needed to cool wort is fixed in the coolant recycle system.
Appendix D: Energy Usage/Energy-Related Process Improvements
Energy Usage Sources (Power consumption obtained equipment technical specifications)
1. Heating the wort
a. Plug-in heater: 2 kW * 2.5 hours = 5 kWh
b. Hot plate: .18 kW * 1.5 hours = .27 kWh
2. Pumping the water
a. To pump at 7.56L/min: .5 kW * .25 hours = .125 kWh
3. Aeration
a. Bubbler: .025 kW * .083 hours (5 minutes) = .00275 kWh
4. Computer Usage for Heating Data
a. .250 kW * 4 hours = 1 kWh
5. Energy for stirring
a. Stir plate: .01 kW * 3 hours = .03 kWh

12. 11
6. Energy for forced carbonation
a. Kegerator: 1.9A*115V = 218.5W.2185 kW * 48 hours of carbonation = 10.448
kWh
7. Total Energy Usage/Final Volume of B
Energy usage ratio (
𝑒𝑛𝑒𝑟𝑔𝑦 𝑢𝑠𝑒𝑑 𝑓𝑜𝑟 𝑝𝑟𝑜𝑐𝑒𝑠𝑠𝑖𝑛𝑔
𝑣𝑜𝑙𝑢𝑚𝑒 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑏𝑒𝑒𝑟
) =
12.375 𝑘𝑊ℎ 𝑜𝑓 𝑒𝑛𝑒𝑟𝑔𝑦
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 𝑜𝑓 𝑏𝑒𝑒𝑟
=
12.375 𝑘𝑊ℎ 𝑜𝑓 𝑒𝑛𝑒𝑟𝑔𝑦
9.465 𝐿 𝑜𝑓 𝑏𝑒𝑒𝑟
= 𝟏. 𝟑𝟎𝟕 𝒌𝑾𝒉/𝑳
Energy Process Improvements
1. Insulated Pot
a. 𝑄 = ℎ 𝑐,𝑎𝑖𝑟 𝐴 𝑝𝑜𝑡(𝑇 𝑤𝑜𝑟𝑡 − 𝑇𝑎𝑚𝑏𝑖𝑒𝑛𝑡)
b. 𝑄 = (.1045
𝑘𝐽
𝑠∗𝑚2 𝐾
)(1𝑚2
)(3°𝐶)
c. 𝐻𝑒𝑎𝑡 𝑙𝑜𝑠𝑠 = .44
𝑘𝐽
𝑠
= .44 𝑘𝑊 ∗ 2.59 ℎ𝑜𝑢𝑟𝑠 𝑜𝑓 ℎ𝑒𝑎𝑡 𝑜𝑝𝑒𝑟𝑎𝑡𝑖𝑜𝑛 = 1.1 𝑘𝑊ℎ
2. Automatic temperature control
a. Why: to prevent unnecessary increase of power
3. Kegerator Maximized Usage
a. Current process: Keg only one batch of bee at time
b. Fix: Keg three batches of beer simultaneously as the kegerator consumes the same
amount of energy regardless of how many batches are placed in the keg fridge.
4. Computer Maximized Usage
a. Current process: track temperature data of one batch
b. Fix: Track temperature data of two batches (we have two thermocouple data
collection systems in the lab).
5. Scale up production volume
a. Kegerator (3 batches per kegging)
i. Current energy use ratio: 10.448 kWh/9.465 L of beer = 1.10
ii. Scale up to 3 batches for kegging: 10.448 kWh/(9.465 L *3) = .36
b. Computer (Collect temperature data for two batches)
i. Current energy use ratio: 1kWh/9.465 L of beer: .10
ii. Double batches for temperature measurement: 1 kWh/(9.465 L of beer *2
batches)=.05
Appendix E: Water/Energy Usage Comparisons
Table: Our produced beer’s water and energy usage compared against craft breweries’ water and
energy usage ratios.
Environmental
Consideration
Our Produced Beer BIER Sierra Nevada
Water Usage 16.8 L/L 4.28 L/L 3.83 L/L
Energy Usage 173 kWh/BBL 66 kWh/BBL 14.04 kWh/BBL
Appendix F: Carbon dioxide equivalent emissions due to energy usage (Batch and Craft
Brewery Production Scaleup)

13. 12
 Batch:
9.42 𝑘𝑊ℎ
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 𝑜𝑓 𝑏𝑒𝑒𝑟
∗
1 𝑀𝑊ℎ
1000 𝑘𝑊ℎ
∗
653 𝑙𝑏 𝐶𝑂2−𝑒𝑞
1 𝑀𝑊ℎ
= 2.46 𝑙𝑏 𝐶𝑂2 − 𝑒𝑞
 Craft Brewery:
9.42 𝑘𝑊ℎ
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 𝑜𝑓 𝑏𝑒𝑒𝑟
∗ (1.86 ∗ 108
𝑔𝑎𝑙𝑙𝑜𝑛𝑠) ∗
1 𝑀𝑊ℎ
1000 𝑘𝑊ℎ
∗
653 𝑙𝑏 𝐶𝑂2−𝑒𝑞
1 𝑀𝑊ℎ
= 4.58 ∗ 108
𝑙𝑏 𝐶𝑂2 − 𝑒𝑞
Comparison of Our Beer versus Industry energy emissions per barrel (BBL)
Environmental
Consideration
Our Produced Beer
[𝑙𝑏 𝐶𝑂2 − 𝑒𝑞]
BIER [𝑙𝑏 𝐶𝑂2 − 𝑒𝑞] Sierra Nevada
[𝑙𝑏 𝐶𝑂2 − 𝑒𝑞]
Emissions 113 43.1 9.17
Appendix G: Economic Analysis of the bee production process
Economic Analysis (Per 2.5 gallon batch)
 Raw Ingredients: $26.29
 Utilities: $0.13/kWh*12.375 kWh/batch of beer = $1.61
 Water: $0.002/gallon of water * 30 gallons of water=$0.06
 Total Cost: $27.96 per 2.5 gallon batch
 Six Pack Cost (.5625 gallons) = $6.29 per six pack
Economic Analysis (Scale up to 186 million gallon production)
 Raw Ingredients:
$26.29
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠
∗ 186 𝑚𝑖𝑙𝑙𝑖𝑜𝑛 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 = $1.96 𝑏𝑖𝑙𝑙𝑖𝑜𝑛
 Utilities:
$1.61
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠
∗ 186 𝑚𝑖𝑙𝑙𝑖𝑜𝑛 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 = $119.78 𝑚𝑖𝑙𝑙𝑖𝑜𝑛
 Water:
$0.06
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠
∗ 186 𝑚𝑖𝑙𝑙𝑖𝑜𝑛 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 = $446,440
 Total Cost: $2.08 billion
Economic Analysis with Applied Savings from environmentally driven process improvements
 Raw Ingredients:
$26.29
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠
∗ 186 𝑚𝑖𝑙𝑙𝑖𝑜𝑛 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 = $1.96 𝑏𝑖𝑙𝑙𝑖𝑜𝑛
 Utilities
o 5 kWh (plug-in heater) + .27kWh (hot plate)+.125 kWh (water
pumping)+.00275kWh (aeration) + .5 kWh (halved by collecting two batches
worth’ of temperature data on the same computer) + .03 kWh (stirring) + 3.48
kWh (cut in third by kegging three batches at a time)= 9.42 kWh
o New utilities cost per batch: $0.13/kWh*9.42 kWh/batch of beer=$1.23
o Scale up cost:
$1.23
2.5 𝑔𝑎𝑙𝑙𝑜𝑛𝑠
∗ 186 𝑚𝑖𝑙𝑙𝑖𝑜𝑛 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 = $91.72 𝑚𝑖𝑙𝑙𝑖𝑜𝑛
o Savings: $119.78 million-$91.72 million =$28.06 million
 Water
o 121 gallons of water needed to cool the wort if a coolant recycle system is
implemented
 This caps the amount of water you need to cool the wort (not dumping
water into the sink after each batch)
o Scale up cost (recycle coolant system):
$0.002
𝑔𝑎𝑙𝑙𝑜𝑛 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟
∗ 121 𝑔𝑎𝑙𝑙𝑜𝑛𝑠 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟 =
$0.25
o Savings: $446,440-$0.25=$446,439
 Adjusted Total Cost with process improvements (more effective energy/water usage)

14. 13
o Total Cost: $2.05 billion
o Total Savings: $28.5 million
o Adjusted six pack cost: $2.05 billion/186 million gallons *.5625 gallons (one six
pack) =$6.19 per six pack
Appendix H: Oral Presentation Slides

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