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Hydrogen Fueling Station Team #: 2 Course #: EDSGN 100 Section #: 2 Submitted to: Ming-Chuan Chiu Date: 4/27/11 Jonathan Retter email@example.com www.personal.psu.edu/jer5272 Christopher Bergman firstname.lastname@example.org www.personal.psu.edu/ctb5101 Karim Kabbara email@example.com www.personal.psu.edu/kyk5150 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 environment. 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 Durability Efficiency Storage Cost Aesthetics 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 hydrogen 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 Electrolysis 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  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 biomass. 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  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 Methods Criteria Biomass Solar Water Splitting Steam Reformation *Renewable + + + 0 Cost - - - 0 Location 0 - + 0 Independent *Pollution 0 + + 0 Maintenance 0 + 0 0 Mass 0 + - 0 Production *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 water. 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 Maintenance 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 Conclusions 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.  Stats 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 Energy Solar Rays Materials Provides Converts Hydrogen Material Material Fuel Natural Needed to Needed to Gas produce produce Hydrogen Hydrogen Water Fuel Fuel Signal Pressure Pressure Lock Lock Unlock Pull Trigger Pressure Unlock The concept 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 Tanks 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 Electrolysis 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 well. 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 Concepts 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 Cost 4% 5 .2 3 .12 5 .2 (Consumers) Cost 5% 4 .2 3 .15 4 .2 (Producers) Storage 9% 2 .18 3 .27 3 .27 Aesthetics 7.2% 3 .216 3 .216 4 .228 Additional 7.2% 4 .228 3 .216 3 .216 Features 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 production. 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 household. 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.  = 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 . 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 Results Solar AC Energy Month Radiation Energy Value 2 (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. Safety 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 . 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 . 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. Maintenance 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. Electrolyzer 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. Safety 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. Maintenance 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. Compressor 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. Safety 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. Maintenance 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 . A liquid form of natural gas, also known as LNG, will need to be stored at under minus 258 degrees Fahrenheit . Both tanks will be insulated, minimizing the effect of evaporation. Safety 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. Maintenance 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. Dispensers 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. Safety 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. Maintenance 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 needs. Efficiency 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. Durability 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. Cost 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. Storage 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 days. Aesthetics 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 well. 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  http://www.afdc.energy.gov/afdc/fuels/natural_gas_blends.html https://cms.psu.edu/section/content/default.asp?WCI=pgDisplay&WCU=CRSC NT&ENTRY_ID=B9EE674B3FAC48FC81937D4EC0C8927A http://www1.eere.energy.gov/hydrogenandfuelcells/production/biomass_gasific ation.html  http://www.kqed.org/quest/blog/tag/solar/  http://planetlight.blogspot.com/2011/02/free-energy-discovered-infinite- battery.html http://www.rowan.edu/colleges/engineering/clinics/cleanenergy/rowan%20univ ersity%20clean%20energy%20program/Energy%20Efficiency%20Audits/Energy %20Technology%20Case%20Studies/Geothermal/geothermal.html  http://mapserve3.nrel.gov/PVWatts_Viewer/index.html  http://www.cityofirvine.org/  http://www.newagesolar.com/products.php  http://www.nasa.gov/mission_pages/shuttle/launch/LOX-LH2-storage.html  http://www.canveylng.co.uk/what-is-lng.html  http://venturebeat.com/2009/01/14/solar-panels-pose-an-environmental- hazard-claims-report/  http://www.eco-smart.org/productdocs/1-Eco-$mart- Solar_Dual_Axis_Tracker.pdf
"Hydrogen Fueling Station Team _ 2 Course _ EDSGN 100 Section "