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Hydrogen Fueling Station Team _ 2 Course _ EDSGN 100 Section


									Hydrogen Fueling Station
Team #: 2

Course #: EDSGN 100
Section #: 2

Submitted to: Ming-Chuan Chiu
Date: 4/27/11

Jonathan Retter

Christopher Bergman

Karim Kabbara
1.0 Abstract
The objective of this report is to explain the process our team went through to develop a
hydrogen fueling station. The current problem that exists in the field of fueling one‟s car
is that gasoline, a nonrenewable fuel that causes pollution, is still being used even
though it destroys the very environment we live in. Gasoline will not be around forever,
so a switch to hydrogen fuel needs to occur. Through our partnership with Air Products,
we took the first step in designing a hydrogen fueling station that can allow this switch
from gasoline to occur. Through research of customer needs and previous methods to
produce hydrogen, concept sketches were developed and evaluated until one final
design was created. This final design solves the gasoline problem by providing
independent hydrogen fueling stations run by renewable energy that can be imputed to
replace any existing gasoline stations.
Table of Contents
   2.0 Introduction
   3.0 Mission Statement
   4.0 Customer Needs Analysis
   5.0 External Research
      5.1 Literature Search
      5.2 Patent research
      5.3 HCNG Survey
      5.4 Hydrogen Survey
      5.5 Benchmarking
      5.6 Choosing an Energy Source
      5.7 Choosing a Location
   6.0 Concept Generation
   7.0 Concept Selection
   8.0 Embodiment Design and Final Design Description
      8.1 Hydrogen Production Process
      8.2 Calculations
      8.3 Examination of Materials
      8.4 Station Layout and Description
      8.5 Cost
   9.0 Conclusions
      9.1 Meeting Customer Needs
      9.2 Building a Hydrogen City
   10.0 References

2.0 Introduction
Our problem is the set-up of current fueling stations as well as energy sources used to
run them. Current fuel stations use fossil fuels to power city transportation while optimal
fuel stations would use renewable energies, such as hydrogen or a hydrogen and
natural gas mixture, for a fuel. This new fuel and fueling station would provide an
innovative basis for this, and other cities, to begin developing newer and cleaner forms
of energy. The optimal result would be a development of a station and fuel that does not
hurt our environment.
        Our intentions are to provide our selected city with a hydrogen fueling station that
is supported through solar power. Solar Powered energy will provide enough electricity
for the hydrolysis of water generating our hydrogen fuel. The issues that come up with
this process are the area in which we apply our solar energy and the accessibility of a
water source. Luckily through some research we were able to find an area that would
allow us to efficiently produce hydrogen fuel with as little energy as possible. Irvine,
California is one of the sunniest places in the continental United States providing the
area with approximately two hundred seventy-two days of sun per year. Since we are
choosing to make the fuel through hydrolysis, we then researched to see if there was
access to water in Irvine. Irvine has two lakes, which can easily provide enough water
for our fueling station. Secondly, the coast is only twelve miles away giving us access to
the vast Pacific Ocean. Logistically, Irvine is a perfect city to adapt to our newly
incorporated energy. The city of Irvine was designed to provide a simple and easy life
for its citizens. Also, Irvine is the third most solar powered city in the United States
further making it easier for us to complete our task. Another aspect that we recognized
in Irvine is the high amount of revenues and low amount of expenditures providing
enough support from the city itself to incorporate a new fueling station.
         Air Products (the company who hired us) requires a plan for a Hydrogen/Natural
Gas mixture fuel station system that will take over as primary fueling stations for a city
of our choice. These fueling stations must be able to meet the needs of the consumers
in the city. It must fit the specifications that it can produce Hydrogen at both 350 BAR
(5,000 psi) and 700 BAR (10,000 psi) for both passenger cars and commercial
transportation vehicles. The fuel must also be a Hydrogen/Natural Gas blend that
contains up 30% hydrogen at 250 BAR (3,626 psi) pressure to supply the vehicles.
These gas stations will minimize, or optimally eliminate, negative effects on the
         To accomplish these requirements and reach our goal of a renewable, zero
pollution hydrogen fueling station, a schedule was created as shown below. Sticking to
this schedule reminded us of our priorities and helped us to have good time
management throughout the project.

Table 1: Schedule
3.0 Mission Statement
Our intention is to provide the city of Irvine with a innovative and efficient hydrogen
fueling station in order to successfully turn the illustrious Irvine into a the biggest
Hydrogen city in the United States. In this case, our Hydrogen station will use Solar
Energy to ignite our electrolysis process in order to produce hydrogen fuel and
hydrogen compressed natural gas. Our state of the art design will allow Irvine and its
citizens a smooth transition between the senile world of oil and gasoline and into the
realm of Hydrogen fueling.

4.0 Customer Needs Analysis
To bring about focus for our design, a list of customer needs was established. Due to
the fact that we are in essence working for both Air Products and actual customers to
our station, needs from both groups were considered. Through research of the Air
Products requirements and of current gas stations, the following list was established. In
general, the first five needs are those from Air Products, and the last two (Aesthetics
and Additional Features) are aimed more towards actual customers.

                    User Friendly
                    Additional Features

To make this list even more accurate, each need was ranked in a hierarchy structure,
which compared each need to each other. The results and weights (or importance) of
each need are depicted in the table below.
Table 2: Main Category Rankings

Each main need category was then given subcategories to further define what each
need entailed. Each of the subcategories were then ranked in a similar process, as
shown below with the efficiency subcategories. To avoid excessive repetition, the other
six subcategories ranking tables were omitted from this report, as the same process
was used for all seven of the subcategories.

Table 3: Efficiency Subcategory Rankings
After ranking all main and sub categories, the following list was obtained, showing the
weights of each main category and sub category.

(Overall Importance, Importance within main category)

   1. Efficiency (.364, .364)
      1.1 High Quality H2 (.026, .0714)
      1.2 Renewable Energy Source (.13, .357)
      1.3 Low Cost of Energy (.052, .143)
      1.4 Low Environmental Impact (.13, .357)
      1.5 H2 and HCNG Dispensers (.026, .0714)
   2. User Friendly (.182, .182)
      2.1 Low Pumping Time (.091, .5)
      2.2 Familiar Dispensing Mechanism (.091, .5)
   3. Durability (.125, .125)
      3.1 Low Maintenance (.0178, .143)
      3.2 Long Lasting Equipment (.0178, .143)
      3.3 Safe (.089, .714)
   4. Cost (.091, .091)
      4.1 Low Cost Per Station (.0607, .667)
      4.2 Low Initial Cost (.0303, .333)
   5. Storage (.091, .091)
      5.1 Large Storage (.065, .714)
      5.2 Underground (.026, .286)
   6. Aesthetics (.072, .072)
      6.1 Modern Look (.009, .125)
      6.2 Familiar Units (.036, .5)
      6.3 Hidden Features (.018, .25)
      6.4 Flows with community (.009, .125)
   7. Additional Features (.072, .072)
      7.1 Mini Mart (.072, 1)
The following table restates the previous list without the weights, but in a more
straightforward importance ranking (1, 2, 3, 4 and so on).

Table 4: Customer Needs Importance
No.                                              Need                                     Imp.
 1         Efficiency     Renewable Energy Source                                           1
                          Low Environmental Impact                                          1
                          Lost Cost of Energy                                               3
                          High Quality Hydrogen                                             4
                          Hydrogen and HCNG Dispensers                                      4
 2       User Friendly    Low Pumping Time                                                  1
                          Familiar Dispensing Mechanism                                     1
 3         Durability     Safe                                                              1
                          Low Maintenance                                                   2
                          Long Lasting Equipment                                            2
 4            Cost        Lost Cost Per Station                                             1
                          Low Initial Cost                                                  2
 5          Storage       Large Storage                                                     1
                          Underground/Hidden                                                2
 6        Aesthetics      Familiar Units                                                    1
                          Hidden Features                                                   2
                          Modern Look                                                       3
                          Flows With Community                                              3
 7    Additional Features Mini Mart                                                         1

5.0 External Research
The bulk of our external research cam in the form of the surveys of HCNG and
hydrogen production, research of renewable energy, benchmarking, and research about
choosing a city. A literature search and patent search were done as well.

       5.1 Literature Search
       Hydrogen is slowly becoming the new way to run our fast moving and highly
       developed nation. Without gasoline to fuel our vehicles our economy and way of
       life will crumble. Unfortunately, gasoline prices are skyrocketing and new forms
       of fueling are in necessity of being developed. Luckily for earthlings such as
       ourselves Hydrogen is found in exorbitant amounts and we have the capabilities
      of converting it into fuels to replace gasoline. We have decided to use the power
      of the sun to produce potential energy. Water is also located in abundance and
      through the process of electrolysis we have the capabilities of applying potential
      energy to split water into hydrogen and oxygen gas. Hydrogen fueling in an
      efficient and energy saving way to produce the fuel to potentially run our nation.

      5.2 Patent Search

      US Pat. 7048839
           System and method for generating high-pressure hydrogen
      US Pat. 7866354
           Hydrogen tank filling station and method of filling hydrogen tank with
      US Pat. 10340879
           Hydrogen fueling station
      US Pat. 12747261
           Hydrogen storage tank
      US Pat. 7152675
           Subterranean Hydrogen Storage Process
      US Pat. 4686322
           Solar panel
      US Pat. 4995377
           Dual Axis solar tracker assembly
      US Pat. 537179

The table below formats the patents searched by matching them with their
corresponding field of use.
Table 5: Patents

5.3 HCNG Survey
For our project, the HCNG fuel needed for the public transportation buses will be
30% hydrogen based, with the remainder being natural gas. The main purpose of
this HCNG fuel is to reduce the emissions of larger vehicles while still having the
power to run them. For example, when compared to natural gas alone, HCNG
reduces the nitrogen oxide emissions of a vehicle by 55%. The chart below
shows the differences in the emissions of the natural gas fuel (CNG) and the
blended natural gas-hydrogen fuel (HCNG).

Table 6: Pros and Cons of HCNG
                  Pros                                            Cons
           Reduces emissions                               Not as fuel efficient
   Stepping stone towards H2 vehicles
 Can be in same dispensing station as H2

5.4 Hydrogen Survey
Hydrogen itself is not an energy source, it is rather an energy carrier that must be
created from other primary energy sources. The diagram below depicts the
different methods of creating hydrogen from these energy sources.

For a more detailed look at how these processes work, we chose four of the
major methods to examine further. These four are biomass energy, solar PV
energy, and thermo chemical water splitting sources along with the standard
steam reformation for comparison purposes.
Production from Biomass
First off, biomass is an organic resource that includes crop and forest residues,
municipal solid waste, and animal wastes. Due to the reproduction of these
materials over time, biomass is considered a renewable resource.

These biomass materials are then put under pressure and extreme temperatures
that converts the biomass into a gaseous mixture of hydrogen, carbon monoxide,
and a few other compounds. The chemical reaction involved looks as follows:

           C6H12O6 + O2 + H2O → CO + CO2 + H2 + other species [3]

From here, absorbers or special filters can remove the hydrogen from the other
gases. The hydrogen can then be stored and used as a fuel itself.

This process is about 50% efficient and costs six times as much as natural gas
per unit energy. Due to that it runs off of natural materials, hydrogen production
from biomass can be conducted nearly anywhere.

The table below features the pros and cons of hydrogen production from

Table 7: Pros and Cons of Biomass Production
                 Pros                                     Cons
           Abundant resource                     High cost of production
               Renewable                     High cost of biomass feedstock
   Biomass consumes carbon dioxide           Not a completely clean process
     Can be used nearly everywhere

Production from Solar Photovoltaic

Solar PV can be broken up into two different categories: First the actual solar
panels, and then the electrolysis of water to create the hydrogen.

The solar panels are made from silicon, which is used to capture the sun‟s rays
and convert them into electricity. The sun‟s rays are actually composed of
photons, which are particles of solar energy. These photons energize the silicon
atom‟s valence electrons, giving them enough energy to escape the atom. A built
in electric field in the panels guides the electrons in an orderly fashion to create a
current, and thus electricity.
This process works best in areas with a lot of sunlight. The map below shows the
levels of solar radiation across the United States, with red being the highest and
blue/purple the lowest.

Once the electricity is created, it can be used to separate the hydrogen from        [4]
water via electrolysis. This process is pretty straightforward. The electricity is
used to create both positive and negative terminals that are placed in the water.
These terminals then “split” the water into hydrogen and oxygen. The hydrogen,
which is positively charged, will be attracted to the negative terminal, while the
oxygen, which is negatively charge, will be attracted to the positive terminal.
Once separated, the hydrogen can be collected and the oxygen can be released
into the air.

This process is depicted on the below on the left, while the chemical equation is
featured below on the right.

Even though electrolysis is a completely clean method of producing hydrogen, it
is only 10% efficient and costs nine times of much as natural gas per unit energy.
A table listing the pros and cons is featured below.

Table 8: Pros and Cons of Solar PV Production
                  Pros                                     Cons
              “Free” Energy                           High initial costs
               Renewable                            Weather dependent
      No carbon dioxide emissions                Only works during the day
            No noise pollution              Pollution during production (Silicon)
     Can be used in remote locations                   Poor efficiency
      Low/No maintenance needed

Production from Thermo Chemical Water Splitting
Thermo Chemical water splitting via the sulfur – iodine cycle (SI cycle) is a
method to create hydrogen through three chemical equations. The first equation
is the combinations of iodine, water, and sulfite into HI and H2SO4. The next two
are the decompositions of the two products that result in hydrogen, oxygen,
iodine, water, and sulfite. The iodine, water, and sulfate were the reactants at the
start, so they continue onto another cycle, while the hydrogen and oxygen are
products that can be stored (hydrogen) or released (oxygen). The reactions are
shown below.
Each reaction requires large amounts of heat, up to around 830 0C. The heat can
be obtained via multiple different sources, such as solar, wind, or fossil fuel
energy. This means thermo chemical water splitting can occur in a wide range of
locations as long as an adequate heat source can be obtained.
Thermo Chemical water splitting is 40% efficient and costs 18 times the cost of
natural cost per unit energy.

Table 9: Pros and Cons of Thermo Chemical Water Splitting Production
                   Pros                                  Cons
          Continuous operations            Very high temperatures involved
       Oxygen is the only emission               Relatively small scale
   Renewable heat sources available
         Relatively high efficiency

Production from Steam Reformation
Steam reformation is not a renewable way to produce hydrogen, but it is currently
the standard in hydrogen production. For example, 95% of the hydrogen
produced in the United States is done so via steam reformation. For this reason,
we thought it would be a good idea to compare steam reformation to the newer
methods to produce hydrogen, because we will be converting from steam
reformation to a renewable source.

Steam reformation begins with natural gas heated up to very high temperatures
(7500C – 8000C). At these temperatures, the hydrocarbons in the natural gas
react with the steam to form carbon monoxide and hydrogen. This process is
described by the chemical equation below:

              CH4 + H2O  CO + 3H2 + 191.7 kJ/mol
The carbon monoxide created is separated from the hydrogen and undergoes
further reactions with steam to produce more hydrogen and carbon dioxide. This
is accomplished by both high and lower temperature shifts during the reaction.
This process is described by the chemical equation:

                CO + H2O  CO2 + H2 – 40.4 kJ/mol
The hydrogen from both processes is added together. Impurities in the forms of
carbon dioxide, carbon monoxide, and hydrogen sulfide will exist and will need to
be filtered out.

This process can be carried out nearly anywhere. All that is needed is a plant to
perform the reformation, and trucks to transport the natural gas to the plant.
Steam reformation is 70% efficient, and the hydrogen produced costs three times
the cost of natural gas per unit energy. The table below features pros and cons of
steam reformation.

Table 10: Pros and Cons of Steam Reformation Production
                  Pros                                    Cons
                 Efficient                 A lot of carbon emissions produced
           Relatively low costs               Impurities exist in the product
    Know and widely used technology                   Not renewable

Benchmarking Hydrogen Sources
To determine the best possible method to produce hydrogen, a matrix was set up
to rank which of the four methods would best fit our needs. To do this, a list of
criteria was established based on the overall expectations of the project. The list
of the criteria, in no specific order, is shown below in the table.

Table 11: List of Criteria
          Criteria                                   Description
        Renewable                      The method only uses renewable energy
            Cost                   The hydrogen is produced relatively inexpensively
   Location independent                  Method can be used across the U.S.
         Pollution                        The method involves no pollution
       Maintenance                                 Easy to maintain
     Mass Production                       Can be made in large quantities
          Safety                                    Method is safe
         Efficiency                           High output to input ratio
Using this list of criteria, a design matrix was created, which ranked the four
methods of creating hydrogen. This was accomplished by using a plus (+) minus
(-) system to see how different methods compared to the benchmark. For this
table, the benchmark was steam reformation, because it is the industry standard
at the present time. The benchmark is given all 0‟s as the other three methods
are compared to it. Whichever method receives the highest positive score will be
ranked the highest.

Table 12: Hydrogen Producing Method Screening Matrix
  Criteria      Biomass        Solar     Water Splitting             Steam Reformation

*Renewable            +                 +                +                     0
     Cost             -                 -                -                     0
   Location           0                 -                +                     0
  *Pollution          0                 +                +                     0
Maintenance           0                 +                0                     0
     Mass             0                 +                -                     0
    *Safety           +                 +                0                     0
  Efficiency          0                 -                -                     0

  Sum +‟s            2                 5                3                      0
  Sum 0‟s            5                 0                2                      8
  Sum –„s            1                 3                3                      0
 Net Score           1                 2                0                      0
   Rank              2                 1                3                      3
 Continue            No               Yes               No                    No

Solar powered electrolysis was chosen as the method to produce the hydrogen
for the city, as it met the criteria the best out of the four options.
*The main objectives of this project are to create system of hydrogen fueling
stations in a city that are:
        1) Powered by renewable energy
        2) No pollution created
        3) Produce hydrogen safely
Extra consideration was taken into these three criteria, and as solar powered
electrolysis was the only method to receive a “+” in all three, it was the obvious
choice despite the close outcome in net scores of the four methods.

Method of Hydrogen Production = Solar Powered Electrolysis
      5.5 Benchmarking
      Benchmarking of fueling stations was then completed, using a gasoline station,
      current hydrogen station, and what we plan on creating as an improved hydrogen
      station. The results are shown below, and help to further explain why we plan to
      build an improved hydrogen station. The criteria used were our customer needs
      described earlier.

      Table 13: Fueling Station Comparison

Benchmarking was then done for methods of transportation of hydrogen. Pipelines,
trucks, and onsite production were all considered. In the end, onsite production was by
far the best, as no money would need to be spent transferring hydrogen. The criteria for
this table were created via research of how to transport hydrogen.
Table 14: Transportation of Hydrogen

      5.6 Choosing an Energy Source
      For our project, we chose to create hydrogen by electrolysis of water. The energy
      needed for electrolysis would have to be from a renewable resource. The
      following are descriptions of each of the major renewable energy sources.

      Solar Energy
      Solar Panels are groups of Photovoltaic cells that produce electricity by receiving
      the photons of light from the sun. The silicon in the cells converts the photons
      directly into electricity, which can be used in electrolysis to take hydrogen out of

      Table 15: Pros and Cons of Solar Energy
                        Pros                                             Cons
            No Carbon Dioxide emissions                            High Initial Costs
                     Renewable                                   Weather Dependent
                  No Noise Pollution                                Day Time Only
               “Free” source of energy                     Doesn‟t work in polluted areas
                 Possible tax returns                  Pollution created during manufacturing
                  Maintenance Free                        Separate storage device needed
            Can be used in remote areas                 Separate device to convert DC to AC

      The best location for solar panels would be somewhere with a high percentage of
      sunny, non-cloudy days. Solar panels can be stationary, single, or duel axis.
Wind Energy
Wind energy is a straightforward process that involves a wind turbine and a
generator. Naturally occurring wind rotates the turbine, which in turn turns an
alternator, which generates electricity. The electricity then runs down to the base
of the windmill where it can be redirected and used elsewhere.

A major problem with wind energy is that is can be very unpredictable. The
power generated by the windmill relates directly to the wind on that given day.
Having a system powered purely off of wind power could be costly, because one
would have to make more windmills than they think to be sure to have enough
electricity on not so windy days. Then, during the windy days, too much electricity
can be generated which cannot be stored, thus wasting the output of the
windmills. Wind energy would work best as a sidekick to another energy source.

Table 16: Pros and Cons of Wind Energy
                  Pros                                               Cons
      No carbon dioxide emissions                              Noise pollution
            Relatively cheap                             Weather/wind dependent
        Permanent type of energy                              Poor aesthetics
    Can be used anywhere with wind                      Electricity cannot be stored

Tidal Energy
 As with wind energy, tidal energy relies on the same concept of turning a
turbine. In this case however, the turbines are underwater and the water acts as
the air would for a windmill. The water, as the tide goes in and out, turns the
turbine, which again, turns an alternator to generate electricity.

The problem with tidal energy is that it is too limited to the coastal areas of any
country. Again, a whole system of renewable power could not be set up just
using tidal energy. It must be in conjunction with another source.

Table 17: Pros and Cons of Tidal Energy
                  Pros                                             Cons
               Renewable                                 Effects ecosystem of fish
              No pollution                              Tide only goes twice a day
              Very efficient                                 Expensive set up
     Waves exist all along the coast
Geothermal Energy
Geothermal energy uses the turbine concept as well. In an appropriate area
where underneath the surface of the Earth is at extremely high temperatures, a
hole is drilled far down into the Earth‟s crust to reach these areas of high
temperatures. Water is then pumped down the hole, evaporates due to the
extreme heat, comes up as steam in another hole, and turns a turbine that
creates electricity. The diagram below depicts the process.

Like tidal power, geothermal energy is too limited location                    wise.
There are only a few places where temperatures under the Earth‟s surface are
hot enough, and the crust is in the right conditions to drill through. Also, once set
up, the fixtures are quite permanent, having holes drilled down thousands of feet,
leaving little room for change in the future.
Table 18: Pros and Cons of Geothermal Energy
                   Pros                                           Cons
               No pollution                                 High initial costs
                    24/7                                Only exists in a few areas
                  Efficient                                   Health risks
        Inexpensive running costs
          Direct source of power

After weighing all the options, we chose to go with solar power. We did this for a
few reasons. The first of which is that solar power is reasonably portable, can
span the whole U.S., and will not leave any sort of environmental footprint
wherever it goes. This makes it the most environmentally friendly option.

While solar power may not be as efficient as the other sources of electricity, it
makes up for it by being the most environmentally friendly. Adding in the fact of
no maintenance costs, being that solar panels work for 20 years on their own, we
believe solar energy is the direction we should head towards.

The screening matrix below, along with a list of characteristics tested for, further
explains why solar energy was chosen.

Table 19: Characteristics of Renewable Energy
Table 20: Renewable Energy Screening

5.7 Choosing a Location
The city of Irvine is located perfectly in Southern California neighboring major
cities such as L.A and tourist hot spot Laguna Beach. Geographically Irvine has
272 days of sun a year and is located twelve miles away from the west coast. In
this case it is in the perfect area for Hydrogen production through electrolysis,
while using solar energy. In 1959 the University of California hired an architect to
carefully map out Irvine in order to make a flowing and organized city. This
modernized city focuses on clean environmental standards and maintaining the
beautiful aesthetics that have been developed in earlier years. With all this
already established Irvine is the perfect city where we have the capabilities of
developing a high class and flourishing hydrogen city.

A map of solar radiation across the country is shown below, followed by further
facts about Irvine, California.

           City Fundamentals
                o 69.7 Square Miles
                o Elevation: 45 ft
           Population
                o 217000 citizens
                o 3150 square miles
           Top Employers
                o # Employer # of Employees             Sector
                o 1 University of California, Irvine    18,284      Education
                o 2 Irvine Unified School District      2,571 Education
                o 3 Broadcom 2,439 Semiconductor
                o 4 Edwards Lifesciences          1,934 Medical
                o 5 Allergan        1,922 Medical
                o 6 New Century 1,741 Financial
                o 7 Parker Hannifin       1,650 Aircraft
                o 8 St John Knits 1,619 Clothing
                o 9 B. Braun Medical 1,500 Medical
                o 10 Capital Group Companies 1,077 Financial
           City Budget
                o $403.8 million in revenues annually
                o $261.4 million in expenditures annually
6.0 Concept Generation
Concept generation contained three main parts – A black box model, concept
classification tree, and ideas of individual parts.

The black box model, as shown below, is a flow diagram of how our fuelling station
should work, showing inputs to the station, processes, and outputs.
                               Black Box
 Input                         Model                                   Output

  Energy                                                               Electricity
             Provides           Converts              Converts
Sun          Material           materials             Electrical
             Needed to          into                  Energy into
Solar        Make               Electricity           Potential
Panels       Solar                                    Energy
Solar Rays

Materials    Provides          Converts                                Hydrogen
             Material          Material                                Fuel
Natural      Needed to         Needed to
Gas          produce           produce
             Hydrogen          Hydrogen
Water        Fuel              Fuel

Pressure                                                                 Lock
                Pull Trigger               Pressure

               classification tree, featured below, depicts the main features of a fueling station, as well
               as ideas for each one of the main features.

                                    Hydrogen Fueling Station

    Production                Storage               Dispensing            Transportation          Additional Features

Solar                    Over ground              Pressure Locks         Trucking                Mini Mart
Biomass                                           5000 psi (350          Pipes                   Bathrooms
                         Underground              BAR)
Wind                     Tanks                                           On Site                 Car Wash
                                                  10000 psi (700
Thermo                   Off Site Storage         BAR)                                           Oil Change
chemical Water
Splitting                                         Pump Sizes                                     Mechanic

From the main categories in the concept classification tree, concept sketches were
drawn for each and were put in the table below.

Table 21: Individual Concepts

The first column features possible power sources/production methods. They are, in
order, solar panels, biomass, wind power, hydroelectric power, and themochemical
water splitting.

The second column shows three possible storage location - the first being offsite, onsite
above ground, and onsite below ground.

The third show the dispensing mechanisms. For these, we decided to stick with the
current standards that exist today, as in having different sizes of nozzles for the different
pressures of hydrogen. Also sketches of having the dispensers in the same of different
location were considered.

The fourth column show transportation possibilities, those being via truck, pipelines, and
onsite production.

The final column lists additional features, such as a mini mart, mechanic, and car wash.
7.0 Concept Selection
Using parts from the table of individual concepts, five complete concepts were drawn as
shown below.

Concept #1
The first main concept constructed from the individual part concepts features off site wind
powered electrolysis. This wind farm would be located outside of Irvine, and the hydrogen
produced will be transported along with the natural gas to each individual station via pipelines.
Storage for the natural gas and hydrogen will both be buried underground, and brought up to
separate dispensers for hydrogen and HCNG. A mini-mart will be built along with the station.
Concept #2
Featuring off site solar powered electrolysis, concept 2 also faces the challenge of transporting
the produced hydrogen to the individual stations. In this case, the hydrogen is cooled into a liquid
and transported with a truck, while the natural gas comes from a pipeline. The fuels are stored in
above ground tanks and dispensed via the same dispensing machine for hydrogen and HCNG. In
addition to a mini-mart, a car wash was added for user convenience.
Concept #3
This concept produces hydrogen off site by the use of biomass from a landfill, where the
hydrogen is stored as well. Pipelines transport the hydrogen and natural gas to the station, where
hydrogen and HCNG can be individually dispensed in separate areas. As with the others, a mini-
mart is included.
Concept #4
By use of thermo chemical water splitting, concept 4 produced hydrogen off-site by use of varies
chemicals that split water molecules apart at high temperatures. Pipelines transport natural gas
and hydrogen to the station, where both are stored in underground tanks. The fuel can then be
dispensed using the same machine for both hydrogen and HCNG. A mini-mart is included as
Concept #5
Our final concept produces hydrogen on-site by use of solar powered electrolysis at each station.
Solar panels will be placed on top of the mini-mart and car wash to collect the energy from the
sun to run the electrolysis. The water needed, as well as the natural gas, will be trucked in to the
station, where the resulting hydrogen and HCNG will be stored in above ground tanks. The fuels
are dispensed separately in different areas of the station.
Our five concepts were then compared with one another by use of a concept-screening matrix, as
shown below. The selection criteria are the customer needs established earlier in the design
process. For the matrix below, concept number 2 was chosen as the benchmark, or standard, to
compare the other concepts to. As shown, concept number 2 was given all 0’s, while the others
received a + if they met the need more effectively, a – if they did not, and a 0 if the concept was
on par with number 2.

Table 22: Concept Screening Matrix
    Selection Criteria              1              2            3                4              5

    Efficiency                     +               0              -              +              -
    User Friendly                  -               0              -              -              0
    Durability                     +               0              -              0              -
    Cost (Consumers)               0               0              +              -              0
    Cost (Producers)               -               0              +              -              0
    Storage                        +               0              -              +              -
    Aesthetics                     -               0              -              -              -
    Additional Features            -               0              -              -              +

    Sum +‟s                         3             0               2              2             1
    Sum 0‟s                         1             8               0              1             3
    Sum –„s                         4             0               6              5             4
    Net Score                      -1             0              -4             -3             -3
    Rank                            2             1               5              3             3
    Continue?                  Combine           Yes             No            Yes         Combine
                                with #5                                                     with #1

Upon completion of the matrix, concepts number 2 and 3 along with a combination of numbers 1
and 5 were continued to examine further.
#1 and 5 Combined
After examining the concepts we had, we determined none of the above had what we were
looking for, so we pulled our best ideas together into one design. From concept #1, we took the
idea of the pipelines for transporting water and natural gas, because that was the most efficient
(yet high initial cost) method of transporting fuels. We also took the underground storage from
number 1, so the tanks wouldn’t affect the aesthetic appeal of the stations. Producing off-site was
a risk, as if the station went down, all fueling stations in the city would be out of operational, so
we decided to use the on-site solar powered electrolysis to produce the hydrogen form concept 5.
Using a combination of these two ideas, a new concept was created as shown below.
      A concept selection matrix was then used with the remaining concepts. This time, a 1 through 5
      number scale was used to rank each concept, with concept given all 3’s as the benchmark. In
      addition, the selection criteria were given a weight that was the same as its weight in the
      customer needs criteria. The weight was multiplied by the rank to get a weighted score that will
      be added for each category to achieve an overall ranking.

      Table 23: Concept Selection Matrix

                                  #2                            #4                Combination of 1 and 5
 Selection      Weight
                          Ranking   Weighted         Ranking         Weighted     Ranking      Weighted
  Criteria       %
                                     Score                            Score                      Score

 Efficiency     36.4%         2            .728          3             1.092          4              1.456

User Friendly   18.2%         4            .728          3             .546           4              .728

 Durability     12.5%         3            .375          3             .375           5              .625
                    4%        5             .2           3              .12           5                  .2
                    5%        4             .2           3              .15           4                  .2
  Storage           9%        2            .18           3              .27           3                  .27

 Aesthetics       7.2%        3            .216          3             .216           4              .228
                  7.2%        4            .228          3             .216           3              .216
      Total Score                  2.855                       2.985                         3.923
         Rank                        3                           2                             1

      Continue?                     No                          No                           YES

      Our new combined concept performed the best in the selection matrix, scoring nearly 1 point
      higher than the other two concepts. The combined concept of 1 and 5 will now be continued into
8.0 Embodiment Design and Final Design Description
Having chosen our final design, the combination of concepts 1 and 5, a full detailed
description is shown below.

      8.1 Hydrogen Production Process
      The picture below details the entire production process for the production of
      hydrogen and HCNG for our fueling station.
8.2 Calculations
The following calculations/assumptions were used to determine the overall
hydrogen need in the Irvine area, and the energy needed to supply that need.

Irvine, CA
Population: 217,000 people
 In Irvine there are on average 2 cars per household and 2.9 people per
Percentage of people with cars: 69%
 Assume only 60% of those cars get used regularly.
People would use cars on a daily basis: 89,838 people
 Assumption of each car holding 5kg of hydrogen per tank and each car is filled
up 1.5 a week.
Hydrogen needed for cars: 673,785kg of hydrogen per week
 Assumption that there is 1 bus per every 500 people, each bus has a 30kg
tank for a 30% hydrogen blend of HCNG (9kg hydrogen), and each bus is filled
up twice a week.
Number of buses: 434
Hydrogen needed for buses: 7,812kg of hydrogen per week
Total hydrogen needed: 681,597kg of hydrogen per week
 Irvine is known to have 24 gas stations.
Total hydrogen needed per station: 28,399.875 per week  4,057.125kg per
day per station
 For electrolysis, 1kg of hydrogen requires 60kWh of electricity. Solar panels in
Irvine produce on average 709 kWh per meter squared per day. [7]

= 344m2 of solar panels per station (3,692ft2)

8.3 Examination of Materials
The main features of the fueling station include the solar panels, electrolyzer,
compressor, storage tanks, and the dispensers themselves. These features will
be examined further below.

Solar Panels
The source of power for our fueling station will be electricity generated from the
light from the sun via dual axis solar panels. Dual axis solar panels were chosen
over regular fixed panels, because dual axis panels track the sun‟s rays
throughout the day allowing them to receive more solar radiation than panels that
remain in one spot. On a yearly basis, dual axis panels produce 40% more
electricity than an equivalently sized fixed panel [9].

The solar panels are made from silicon, which is used to capture the sun‟s rays
and convert them into electricity. The sun‟s rays are actually composed of
photons, which are particles of solar energy. These photons energize the silicon
atom‟s valence electrons, giving them enough energy to escape the atom. A built
in electric field in the panels guides the electrons in an orderly fashion to create a
current, and thus electricity.

Our location is Irvine, California that receives on average 709 kWh per meter
squared per day. See the results table below.

                   Table 24: Solar Radiation in Irvine
                               Solar         AC      Energy
                    Month     Radiation    Energy    Value
                            (kWh/m /day)   (kWh)       ($)
                        1        5.71          510    66.62
                        2        6.29          508    66.36
                        3        7.28          650    84.91
                        4        8.03          691    90.27
                        5        8.74          771   100.72
                        6        8.97          756    98.76
                        7        9.26          796   103.98
                        8        9.08          775   101.24
                        9        8.00          664    86.74
                       10        6.83          593    77.46
                       11        6.33          544    71.06
                       12        5.51          495    64.66
                     Year        7.51         7753   1012.77
Using the results table and the calculations above, it was determined that 344m 2
(3,692ft2) of solar panels would be needed at each station to meet the fuel
demand of the citizens in Irvine. Each station will have 20 solar panels that are
12ft by 18ft.

Outside of toxic byproducts produced while manufacturing the solar panels
(described below), during the run time of the solar panels, there are no major
safety concerns. The largest concern is during times of harsh winds the panels
may be blown off the roof of the station, possibly causing harm to those below.
To combat this problem, the solar panels automatically are stowed in a horizontal
position during periods of high winds (>43 mph) and slanted positions during
periods of snow. This way, no precipitation or wind can damage the panels [13].
Environmental Concerns
The only environmental concern with solar panels has to do with their production.
The manufacturing of solar panels leads to toxic byproducts such as silicon
tetrachloride that can harm human beings [12]. Proper disposal of these wastes
is necessary in order to not harm the environment.

Outside of the initial production, the actual operation of solar panels does nothing
to harm the environment, as solar panels are a zero emission source of energy.

Dual axis solar panels have very little maintenance. In addition to a 25-year
warrantee, the panels must only be inspected once a year to check for any
possible damages to the panels.

Once the electricity is created, it can be used to separate the hydrogen from
water via electrolysis. This process is pretty straightforward. The electricity is
used to create both positive and negative terminals that are placed in the water.
These terminals then “split” the water into hydrogen and oxygen. The hydrogen,
which is positively charged, will be attracted to the negative terminal, while the
oxygen, which is negatively charge, will be attracted to the positive terminal.
Once separated, the hydrogen can be collected and the oxygen can be released
into the air. The catalyst KOH is used to speed up the reaction.

For electrolysis, 8.9kg of water and 60kWh of electricity are needed to produce
1kg of hydrogen.

Electrolysis is very safe. The only issue is that high potential differences are
involved, so the user could become electrocuted if they came into contact with
the two nodes.

Environmental Concerns
Electrolysis of water really has no environmental concerns. Outside of producing
hydrogen, the only other byproduct is oxygen that is friendly to the environment.

After running for a while, the electrolysis machine must be washed. Over time,
the water erodes some of the metal off of the charged nodes, causing pieces of
metal to enter the water. This, in addition to impurities in the water, dirties the
water, which then must be cleaned. Simply draining the electrolyzer and
scrubbing down the machine will lead to higher efficiency of hydrogen production
in the long run. An annual cleaning is more than enough to keep the machine
operating at a high level.

For our station, three separate compressors will be used, one to get the
hydrogen up to 250 Bar, then 350 Bar, and the last to increase it to 700 Bar. The
250 Bar hydrogen will be blended with natural gas to create HCNG, and the other
two pressures will be used to dispense hydrogen directly to the vehicles.

The only safety concerns would be of any leaks in the compressor. The
compressor itself would have built in checks, shutting the system down in the
case of a leak. Also, the compressor will be made to withstand more than the
maximum 700 Bar hydrogen pressure that will be in the system.

Environmental Concerns
Dealing only with hydrogen, the compressors themselves will have no impact on
the environment.

Each compressor will need to be checked once a week for leaks.

Storage Tanks
The station will feature two storage tanks that will hold liquid hydrogen and liquid
natural gas underground. Storing these fuels in liquid form allows for a higher
volume of fuel to be stored, as liquid is more dense than gas.

The hydrogen must be stored in a tank at minus 423 degrees Fahrenheit [10]. A
liquid form of natural gas, also known as LNG, will need to be stored at under
minus 258 degrees Fahrenheit [11]. Both tanks will be insulated, minimizing the
effect of evaporation.

The main safety issue is keeping the temperature low enough for each fuel to
remain in the liquid state. If too much evaporates into a gas, the pressure will
build up. While there will be pressure release systems for both tanks, releasing
excess hydrogen and natural gas into the air is not ideal.

Environmental Concerns
The concern with these tanks being underground is the possibility of leaks or
explosions. Leaks are the more prominent problem (as it would be hard to ignite
the fuel buried underground), as the natural gas could affect any ground water in
the area.
Computerized systems will monitor the temperatures and pressures of each tank.
The only maintenance that is needed is to make sure the temperatures and
pressures are within safe ranges.

There will be two distinctly different nozzles that will be used for fueling vehicles.
Both will have the same basic shape, with the one dispensing HCNG and the
higher-pressure hydrogen being larger in size. This is because the HCNG and
the higher pressure H2 require safer, stronger, and bigger nozzles. Both will be
made of lightweight metal coated with a rubber covering for easy
maneuverability. A sketch of a nozzle is featured below.

To operate the nozzle, the user must connect the fueling end to the car, allowing
the nozzle to lock into place. One the pressure lock is secure, a green light will
appear on the nozzle handle, signaling that the hydrogen (or HCNG) is ready.
The user can then turn the handle allowing the hydrogen to go into the car via the
pressure differential in the car‟s tank and the compressor.

Dealing with high-pressured gas requires a lot of safety precautions to be taken.
The first was mentioned above about the pressure lock on the fueling end of the
nozzle. Only if no leaks are detected can the fuel begin to flow.

The next deals with the issue of the temperature of the tank becoming too hot for
the gas. First off, the tanks in the cars are built to well exceed the pressure of the
hydrogen being inserted. Also, a sensor in the nozzle detects the temperature,
and if it gets too high, the hydrogen stops flowing until an acceptable temperature
can be reached.

The final safety check is with the hoses that attached the nozzle to the fueling
source. The hoses connect through the ceiling of the station, and if any leaks
were detected, the hoses would be sealed. Also, if they were pulled too hard, a
quick release system would disconnect the hoses from the tanks, minimizing the
amount of hydrogen released into the air.
In case a leak were to occur, there are vents above each dispenser that allows
the hydrogen to escape, preventing the hydrogen from collecting overhead that
could explode upon ignition.

Environmental Concerns
Any environmental concern related to the dispenser would be the release of an
excess amount of hydrogen or HCNG into the air. However, with all of the safety
features, this will not be a problem unless the safety systems fail.

The dispensers themselves are run by computerized sensors that detect leaks,
taking the human factor out of the equation. These will monitor the nozzle for
leaks, and will only need to be checked monthly for any physical damage.

8.4 Station Layout and Description
The overall layout of our fueling station features a few key components, which
are the dispensers, mini mart, solar panels, underground storage, and the
electrolysis/compressor station. The following Solidworks model depicts all of
these, with the electrolysis/compressor station being connected to the minimart.

With this view, the three underground storage tanks can be seen - One for water,
one for hydrogen, and the last one for natural gas. Both the water and natural
gas will be pipelined in, while the hydrogen is made onsite.
The following sketch features the basic layout of the station. For this drawing, the
roof is removed, so the actual pumps can be seen. The overall dimensions are
given, as well as the location of the five pumps. The one pump by itself is the
HCNG pump used for buses. The other four feature the 350 Bar and 700 Bar
hydrogen for cars (a set of both pumps on each side of the pillars). Each pump
will feature a touch screen as well as options to pay via credit/debit card, or cash.
This sketch is of the roof only, depicting the solar panels and vents. There are, as
described in the examination of materials, 20 dual axis solar panels, each of
which is 18ft by 12ft. The vents are a safety precaution in case if hydrogen in the
pumps were to leak. The vents will prevent the hydrogen from building up, which
could result in an explosion if ignited. This roof fits over both the mini mart and
the five pumps.

The following are pictures of our physical prototype. The Styrofoam sections are
pumps, the three rectangular prisms wrapped in masking tape are the
compressors, the largest box is the mini mart, the smaller box is the electrolysis
machine, and the metal pieces are the solar panels. Things no note on the
prototype – the vents in the roof of the station to all any leaked hydrogen to
escape safely into the air, and the car used is close to the scale a regular car
would be, showing the approximant sizes of each feature relative to the car.
8.5 Cost
Using the NPV method (shown below) to determine what price we should charge,
we determined $6 a kg would work best. After development and testing, each
station would cost $1.6 million ($400,000 over 4 periods). Also, because our
hydrogen is produced from solar power (“free energy”), the hydrogen costs us
nothing. The cost is only the initial cost of the solar panels. We then determined
the ongoing cost to produce hydrogen would only be due to the water costs for
electrolysis, and the natural gas costs for the HCNG, which we found to be
roughly a total of $2 per kg of hydrogen.

Table 25: NPV Method
      Given our initial colsts and ongoing costs along with our selling price of $6 per kg
      of hydrogen, the following graph shows when we will begin to make a profit. By
      the 16 period, or four years, each one of our stations should break even and
      begin making a profit.

        Knowing that the current selling price is $5 per kilogram for hydrogen, our price
will be a little high. However, we decided the additional benefit of making hydrogen
renewably without damage to the environment was more important than one extra dollar
per kilogram (see customer needs rankings). Also, after 4 years (once we break even),
we can slower lower our price to become more competitive.

9.0 Conclusions

   9.1 Meeting Customer Needs
   Feature below is an analysis of how our station meets each of our original customer
Our fueling station is completely operational on renewable solar energy. Solar
energy is completely pollutant free, thus being environmentally friendly. Also, our
hydrogen is produced with electrolysis, which is the purist way to produce hydrogen,
allowing our hydrogen to be directly dispensed into the cars, skipping the filter step
required by other production methods. To further our station‟s efficiency, there are
separate pumps for the dispensing of hydrogen and HCNG. This will prevent traffic
jams from occurring at each station.

While solar energy is a great option for Irvine, California, other less-sunny places will
not have the option of solar powered station, making a design location dependent.

User Friendly
To make our station as most user friendly as possible, we kept a lot of the traditional
features of a gas station. This will prevent confusion on the consumer‟s part, as they
will be familiar with the dispensing experience. In addition, a sleeker touch screen
display will be used at each pump with very clear options and instructions.
Customers will also be able to pay with credit/debit cards as well as cash at the
pump, instead of having to go inside the station if they wanted to pay with cash.

Our stations for the most part run themselves. The dual axis solar panels follow the
sun by themselves, protect themselves from dangerous weather, and have a 25-
year warranty. The storage tanks have computer-monitoring systems to make sure
appropriate temperatures are obtained, and pressure release systems in case the
pressure builds up too high. The dispensers have leak checks and pressure checks
built in, as well as have vents above them incase a leak were to happen. All these
features allow our station to run by itself very safely.

In addition, our stations are independent of one another, meaning if one were to
malfunction, all the others in the city would remain operational. This minimizes total
malfunction due to one cause.

The $1.6 million price tag for each of our stations is quite high. However, selling
hydrogen at $6 a kilogram will enable for a profit to be reached at 4 years of
operation, which is a short amount of time considering the initial cost.
The station will feature three underground tanks. The natural gas and hydrogen
tanks (the third is water) will be cooled so the fuels can be kept in liquid form,
allowing more volume of the fuel to be stored. This is essential because hydrogen
can only be made during the day when the sun is out (solar powered), so the more
storage each station has, the more fuel they can dispense at night or on cloudy

The important point for aesthetics is that the station is not over the top in innovation.
Having a station that is too modern will cause confusion in the usage of the
dispensing. To prevent this, our station is a more traditional style station, allowing
the user to feel comfortable will transitioning to hydrogen fuel. Another important
aspect is having the hydrogen tanks underground. This way they are not displeasing
to look at, because no one can see them.

Additional Features
Additional Features is pretty straightforward. Besides a mini mart, our station will
feature a touch screen at each pump, and the ability to pay with cash at the pump as

In the end, we stuck to our customer needs very well. The only concern, as
addressed in the efficiency section, is that our station is location dependent due to
our solar panels. Our station would be a fantastic option in the southern United
States, but not so much the north.

9.2 Building a Hydrogen City
Our hydrogen fueling station will easily and efficiently help to build a hydrogen city.
This is due to the physical layout of our station, as well as our production technique.

The physical layout of each station will be very similar to those for gasoline station.
The pumps will look the same, and will have to same paying process, only with a
different dispensing nozzle. This will enable customers to flow into the new stations
without any issues. They will just continue to do what they have always done, except
now with hydrogen fueling their cars.

Our stations produce hydrogen independently of one another, enabling each station
to be built one at a time and be fully operation at the end, not having to be reliant on
a central production facility. In addition, all we will do is replace the existing 24
gasoline stations in Irvine so the locations and overall scenery of the dispensers will
be the same as before. Also, we will slowly incorporate the city by replacing these
gasoline stations over two years, so no two hydrogen stations are build at once. This
enables us, when the time comes, to replace the solar panels of each station after
  25 years (warranty) one station at a time. This will minimize the amount of stations
  under renovation at one time.

  Overall, the transition from the old age gasoline fuel to the new age hydrogen fuel
  will be very smooth with our new solar powered hydrogen station design.

10.0 References













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