The document discusses the potential impacts of green hydrogen production on freshwater resources and proposes solutions to address this issue. It notes that while electrolysis to produce green hydrogen requires large quantities of water, using waste water from industries could help reduce the strain on freshwater sources. The proposed solutions include using treated industrial wastewater as a feedstock for electrolysis and implementing more water efficient processes and technologies in green hydrogen plants, such as water recycling and advanced cooling systems. This would help ensure green hydrogen production is environmentally sustainable and does not exacerbate water scarcity issues.

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2. THE KATARA TEAM
Ziggy George
Director
Lee Mawira
Developer
Joshua Muindi
Programmer
Joy Kyalo
Designer
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3. Challenge Statement #1 - THE WATER IMPACT OF GREEN HYDROGEN
PRODUCTION
THE PROBLEM
The production of green hydrogen using renewable energy sources is
considered a promising solution for achieving a low-carbon energy
system. However the water impact of green hydrogen calls for
immediate attention. The large quantities of water required for green
hydrogen production through electrolysis and other processes can
strain water resources, particularly in water-scarce regions, and have
potential impacts on aquatic ecosystems. Moreover the energy required
to produce and transport large volumes of water needed for green
hydrogen production can offset green house gas emission benefits of
the process.
Therefore there is need to investigate the water impact of green
hydrogen production and identify potential environmental risks
associated with water use. This problem statement highlights the
critical importance of developing sustainable water management
practices for green hydrogen production to ensure the long-term
viability of this promising low-carbon energy solution. K A T A R
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4. IMPACT OF GREEN HYDROGEN PRODUCTION ON FRESH WATER
Green hydrogen production typically involves the process of electrolysis,
which uses electricity to split water into hydrogen and oxygen. While this
process is considered environmentally friendly since it produces zero
greenhouse gas emissions, it can have a significant impact on freshwater
resources.
According to a study published in the journal Environmental Science &
Technology, producing one kilogram of green hydrogen requires 9 liters
of fresh water. However, it can consume up to 60 liters of water on
average. This means that majority of water is used for cooling purposes
during the electrolysis process and for cleaning the equipment.
In regions where freshwater resources are already under stress, the
impact of green hydrogen production can be significant. For example, in
the Middle East and North Africa, which have some of the largest
potential for green hydrogen production due to their abundant solar and
wind resources, water scarcity is a major issue. In these regions, the
production of green hydrogen could exacerbate existing water stress and
contribute to water scarcity.
Continuing to stress water sources through green hydrogen production
could have severe consequences for freshwater ecosystems, particularly if
unsustainable practices are used. These consequences could include:
• the depletion of groundwater resources
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5. OUR SOLUTION
Waste water from industries can be treated and be
used as feedstock for green hydrogen production.
WASTE WATER
01
WATER EFFICIENT DESIGN AND OPERATION OF THE GREEN
HYDROGEN PRODUCTION PLANT
02
Our solutions are to:
1. Divert from using fresh
water sources and seek to
implement alternative
sources that eases the
stress on fresh water
sources.
2. Introduce innovations to the
green hydrogen plants
making them more water
efficient.
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6. Waste water from industries can be treated and be
used as feedstock for green hydrogen production.
WASTE WATER: Industrial waste water
Optimize the wastewater treatment process: The cost of
wastewater treatment can be reduced by optimizing the
process to reduce energy consumption and increase
efficiency. For instance, using advanced biological
treatment methods such as anaerobic digestion or
membrane bioreactors can reduce the energy required to
treat the wastewater, making the process more cost-
effective.
Use renewable energy sources: One of the major costs of
green hydrogen production is the cost of electricity used
in the electrolysis process. By using renewable energy
sources such as wind, solar, or Biogas , the cost of
electricity can be reduced, making the process more
affordable.
Implement economies of scale: The cost of producing
green hydrogen can be reduced by implementing
economies of scale. This involves building larger
electrolysis units that can produce more hydrogen at a
lower cost per unit.
Use innovative financing models: Innovative financing
models such as public-private partnerships, tax
incentives, and subsidies can help reduce the upfront
costs of implementing the process.
Collaborate with other industries: Collaboration between
industries can help reduce the cost of implementing the
Industrial wastewater can contain a significant
amount of water, which can be treated and purified
for use in electrolysis. The purification process
involves removing contaminants such as heavy
metals, organic compounds, and other pollutants
that may affect the efficiency of the electrolysis
process and the quality of the hydrogen produced.
There are various methods for treating industrial
wastewater, such as sedimentation, filtration, and
biological treatments, that can be used to extract
water suitable for electrolysis. Once the water has
been treated and purified, it can be used as a
feedstock for the electrolysis process to produce
green hydrogen.
According to a study conducted by the National
Environmental Management Authority(NEMA) of
Kenya the average amount of waste water generated
by industries is approximately 3 million m³ per day.
The study also found that major sources of
industrial wastewater in Kenya are from the food and
beverage, textile, and chemical industries. These
industries produce high amounts of organic and
inorganic pollutants that require proper treatment
before being used as feedstock in the green

8. WATER EFFICIENT DESIGN AND OPERATION OF THE GREEN
HYDROGEN PRODUCTION PLANT
02
To maximize the use of water in a green hydrogen plant, it is important to implement water conservation
measures and optimize water usage throughout the hydrogen production process. Here are some ways to
achieve this:
1. Implement water recycling and reuse:
Of the 60kg of water being fed to produce 1kg of hydrogen, 25kg is waste water. This water can be
recycled and reused within the hydrogen production process, reducing the amount of fresh water
needed. For example, water used in the cooling system or for washing can be collected, treated, and
reused. Once the waste water (25kg(s)) has been collected it can be treated using our suggested
membrane technologies and put back as part of the feedstock.
2. Use water-efficient electrolyzers:
Electrolyzers that use less water or operate at higher efficiencies can reduce the water usage per unit
of hydrogen produced. The most water-efficient electrolyzer currently available is the proton
exchange membrane (PEM) electrolyzer. For example, a study published in the journal Renewable and
Sustainable Energy Reviews in 2018 found that PEM electrolyzers can achieve water consumption as
low as 1.3-1.8 liters of water per standard cubic meter (Nm3) of hydrogen produced, which is
significantly lower than the 9-12 liters of water per Nm3 typically required by alkaline electrolyzers.
This represents a water savings of up to 90% compared to alkaline electrolyzers.
Another study published in the International Journal of Hydrogen Energy in 2019 found that a PEM
electrolyzer operated under certain conditions could achieve water consumption as low as 0.89 liters
of water per Nm3 of hydrogen produced. This represents a water savings of up to 95% compared to
alkaline electrolyzers.

9. To reduce the amount of water used for cooling
which is significantly high and could bring negative
impacts as stated earlier, adopting various cooling
methods could prove instrumental in achieving the
goal to reduce the amount of water used for green
hydrogen production.
There are numerous ways to achieve cooling. They
include: Wet cooling, air cooling and liquid nitrogen
cooling.
1) Hybrid cooling systems
Hybrid cooling systems offer a more sustainable and
energy-efficient option due to its wide range of
advantages that include:
• Water consumption: Wet cooling systems use large
amounts of water, typically around 3,000 to 5,000
gallons of water per megawatt-hour (MWh) of
electricity produced. In contrast, hybrid cooling
systems use less water, typically around 500 to
1,000 gallons per MWh.
• Energy efficiency: Hybrid cooling systems are
generally more energy-efficient than wet cooling
systems. According to the National Renewable
2) Liquid Nitrogen Cooling systems
Based on intense research, Liquid Nitrogen is a
highly feasible and advantageous method.
Contrary to using Water for cooling as in Wet
Cooling method which may go up to around
3000 to 5000 gallons of water per megawatt
hour of electricity produced in the plant, Liquid
Nitrogen cooling systems do not require water
for cooling. This goes without saying that the
amount of water used is reduced significantly
thereby achieving our goal.
In addition to this, Liquid nitrogen cooling
systems can be more energy-efficient than wet
cooling systems, as they can achieve very low
temperatures quickly and effectively. This can
lead to improved process efficiency and reduced
energy consumption.
Moreover, liquid nitrogen cooling systems do
not require any water and can be a more
environmentally friendly option compared to
wet cooling systems.
Last but not least, wet cooling systems are
generally less expensive to install and maintain
OPTIMAL COOLING SYSTEMS FOR EFFICIENT WATER
USAGE

10. Nitrifying bacteria can be used to convert the nitrogen
present in waste sludge from food processing plants into
nitrogen gas through a process called nitrification.
Nitrifying bacteria are naturally occurring bacteria that
convert ammonia and nitrite into nitrate, which can then
be further converted into nitrogen gas through a process
called denitrification.
In the food processing industry, wastewater treatment
plants are commonly used to treat the wastewater
generated during food production. These wastewater
treatment plants often use biological processes to remove
organic matter and nutrients from the wastewater before it
is discharged into the environment.
During the treatment process, the wastewater is mixed
with activated sludge, which is a mixture of
microorganisms, including nitrifying bacteria. As the
wastewater passes through the treatment plant, the
nitrifying bacteria in the activated sludge convert the
ammonia and nitrite present in the wastewater into nitrate.
Once the nitrate has been produced, it can be further
converted into nitrogen gas through a process called
denitrification. Denitrification is carried out by a different
group of bacteria that use the nitrate as a source of
oxygen to carry out their metabolic processes. As a result,
the nitrogen in the nitrate is converted into nitrogen gas,
which can then be released into the atmosphere.
Biogas is a byproduct of the anaerobic digestion process used in
wastewater treatment plants to treat organic waste. The biogas is
primarily composed of methane, which can be burned to generate
heat and electricity. This electricity can then be used to power the
cryogenic distillation process used to liquefy the nitrogen gas.
To utilize the biogas still found in the sludge to power the
cryogenic distillation process, a combined heat and power (CHP)
system can be used. A CHP system generates both heat and
electricity from the same energy source, in this case, the biogas.
The heat generated during the combustion of the biogas can be
used to power the cryogenic distillation process, while the
electricity generated can be used to power the other equipment in
the wastewater treatment plant.
By using the biogas still found in the sludge to power the
liquefaction process, the overall energy efficiency of the process
can be improved. This can help to reduce the carbon footprint of
the wastewater treatment plant and make the process more
sustainable and environmentally friendly.
Overall, the use of nitrifying bacteria to convert nitrogen in waste
sludge from food processing plants into nitrogen gas is a
sustainable and environmentally friendly approach to wastewater
treatment. It helps to reduce the amount of nitrogen that is
released into the environment, which can lead to eutrophication
and other environmental problems.
LIQUID NITROGEN PRODUCTION FOR COOLING
SYSTEMS

11. In as much as liquid nitrogen cooling systems offer a
more sustainable and energy-efficient option, they
require careful handling and safety precautions. This
owes to the fact that:
1) Liquid nitrogen is extremely cold and can cause
severe frostbite if it comes into contact with skin. It
can also displace oxygen in enclosed spaces, which
can be dangerous if not properly ventilated.
2) Liquid nitrogen must be stored and transported
under high pressure, which requires specialized
equipment and can pose a safety risk if mishandled.
3) Liquid nitrogen requires specialized equipment and
training to handle safely, which can add to the
overall cost of using this cooling method.
Using liquid nitrogen for cooling saves on a great
amount of water that can now be directed
towards producing green hydrogen solely.
With the reference of using 59 kg of water fed to
the green hydrogen plant for production of 1 kg
of hydrogen, using liquid nitrogen changes the
statistics as follows:
35 kg of the 59 kg of water used for cooling can
be used to produce more hydrogen.
Therefore, the amount of water that will be used
to produce green hydrogen will be:
59 kg - 12 kg(RO waste water) – 2 kg(Electron
De-ionization waste water)
= 45 kg
The amount of hydrogen that can now be
produced will increase to:
45𝑘𝑔
9𝑘𝑔
= 5 kg
IMPACT OF LIQUID NITROGEN COOLING
SYSTEMS ON GREEN HYDROGEN
PRODUCTION

12. 1. Ceramic membrane: The membrane is made up of several layers
of filters that allow water to pass through that keep unwanted
particles out. The thin coatings of chemical substances can be
applied to the different filter levels, such coatings can emphasize
the filtration effect for various uses of the membrane in this case,
an additional special coating makes it even easier for water to
pass through the membrane during the desalination process.
They are advantageous as they require less maintenance than
plastic membranes currently used as they are extremely resilient.
2. Protein based membrane: Inspired by nature, specifically a
certain protein known as aquaporin which forms the pluming
system for fish, plants and humans. Aquaporin move and filter
water through cells and are naturally efficient. They are highly
permeable to water and have high rejection to unwanted
materials. The system is found in our kidneys. This membranes
have a high flux rate (almost double to that of plastic
membranes) compared to plastic membranes and require the
less pressure to operate. This further reduces the energy
requirement for water purification.
Advancements in membrane technology(to be used in treating waste water from industries and H2
plant)
The process of treatment filters the water using the membrane to remove unwanted material like minerals, salts
and bacteria. Advancements in membrane technology currently under research in Singapore include:
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13. Advancements in waste water treatment processes
Capacity upgrade with IFAS
Integrated fixed film activated sludge (IFAS)
describes the combination of film media attached
growth systems in the activated sludge process in
the aeration basin for biological treatment of waste
water. The film media can either be added to the
aeration tank as free floating chips or in the form of
retrievable film media cage units. Both increase
surface area for biofilm growth.
The MLSS increases from 3500mg/l to 5000mg/l.
This equals a capacity increase of 50%.
IFAS ADVANTAGES
• Less sensitive to influent peaks and interruptions
of oxygen supply.
• Reliable and easy to operate.
• Adjustable oxygen supply = energy savings.
• Lower energy costs.(for customer).
The IFAS make use of the oxygen produced as a by
product of green hydrogen production lowering the
cost of commercially obtaining the oxygen.
IFAS ADVANCED APPROACH TO NITRIFICATION AND
DENITROFICATION
Research conducted has shown that under
certain conditions that micro Anoxic Zones
can be formed inside bacterial layers , this
effect is known as Simultaneous
Nitrification and Denitrification (SNDN).
This is especially benefited in submerged
bed reactors . Here micro organisms are
attached to a film media surface and form a
bio film layer . While the top layers of micro
organisms (Nitrifying Bacteria) consume the
available oxygen to oxidize ammonium to
nitrate , the bottom layer of micro
organisms (Denitrifying Bacteria) strip the
oxygen from the nitrates to produce
Nitrogen gas.

14. IMPACTS OF KATARA PROJECT
Producing green hydrogen from
waste water can create new
economic opportunities. The
production of green hydrogen
can create new jobs and
stimulate economic growth in
areas where waste water
treatment plants are located.
Additionally, as the technology
for producing green hydrogen
becomes more efficient, the cost
of producing it will decrease,
making it more economically
viable for a wider range of
applications.
Producing green hydrogen from
waste water can have a positive social
impact. The use of green hydrogen
can reduce dependence on fossil
fuels and contribute to a more
sustainable energy future.
Additionally, the production of green
hydrogen can create new job
opportunities, particularly in areas
where there are already water
treatment plants.
Producing green hydrogen from
waste water can have a positive
environmental impact. Using
industrial wastewater as a
feedstock for green hydrogen
production has several
advantages.
Firstly, it provides a sustainable
way to treat industrial
wastewater, reducing water
pollution and promoting a
circular economy.
Secondly, it allows for the
production of green hydrogen
from a readily available and
abundant source of water,
reducing the need for freshwater
resources.
Lastly, it supports the transition
towards a sustainable and
Economical Environmental Social
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15. FEASIBILITY ANALYSIS
FEASIBILITY OVERVIEW KATARA
Technical feasibility
This refers to whether the technology required for the
production of green hydrogen from waste is available and
mature enough to be implemented at scale. This would
include factors such as the efficiency of the hydrogen
production processes, the scalability of the technology, and
the availability of necessary equipment and infrastructure.
As green hydrogen production is still in its
developmental stages and currently still under
planning in Kenya , adoption of The Katara Project
plan with currently existing technologies would prove
to be efficient in green Hydrogen production. Further
adoption and commercialization of upcoming
technologies would result to greater production
efficiency than the current technologies in use.
Economic feasibility
This considers whether the production of green hydrogen fr
om
waste water is economically viable, taking into
account the cost of the technology, operation and maintena
nce
costs, and the market demand for green hydrogen.
The race to zero carbon emission is driving both the
global and local economy to adopt greener sources
of energy. In line with Kenya’s goal to produce 100
Million tones of green hydrogen by the year 2030 ,
The Katatra Project offers solution to reducing the
cost of green hydrogen production by using cheap
renewable sources i.e. solar energy and using alkaline
electrolyzers for green hydrogen plants that is cost
effective.
Environmental feasibility
This examines whether the production of green hydrogen fr
om
waste water is environmentally sustainable,
including considerations such as energy requirements, resou
rce
availability, and potential environmental impacts of the
technology.
Use of renewable energy for powering the plants
associated with the Katara Project promises a greener
future free of carbon emission. The water sources
cited in our project i.e. recycling of industrial waste
water and use of efficient green hydrogen plant
design and operation reduces the strain on fresh
water sources and the depletion rate of non-

16. FEASIBILITY OVERVIEW KATARA
Social feasibility
This assesses whether the production of green hydrogen
from waste water is socially acceptable and beneficial to
local communities, taking into account factors such as job
creation, access to clean water, and impacts on human
health and well-being.
Implementation of Katara will clearly lead to
massive job creation for both skilled and un-skilled
laborer's . Treatment of industrial waste water
reduces contamination of water and food sources
that may cause health deterioration of the locals.
Regulatory feasibility
This examines whether the production of green hydrogen
from waste water is in compliance with relevant laws and
regulations, including those related to water quality,
energy production, and environmental protection.
Our research and statistics were based on
information provided local bodies such NEMA ,KREA
and Kenya Bureau of Statistics.
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