Life-Cycle Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power

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1 report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report energy center Report Summary Renewable Hydrogen Demonstration and Education Project Life-Cycle Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power January 2003 April, 2002 ENERGY CENTER OF WISCONSIN

2 Report Renewable Hydrogen Demonstration and Education Project January 2003 Prepared by Virent Energy Systems, LLC 100 South Baldwin Street, Suite 206 Madison, WI Contact: Kenneth Kenyon Prepared for 595 Science Drive Madison, WI Phone: Fax:

3 Copyright 2003 Energy Center of Wisconsin All rights reserved This document was prepared as an account of work conducted by the Energy Center of Wisconsin (ECW). Neither ECW, participants in ECW, the organization(s) listed herein, nor any person on behalf of any of the organizations mentioned herein: (a) makes any warranty, expressed or implied, with respect to the use of any information, apparatus, method, or process disclosed in this document or that such use may not infringe privately owned rights; or (b) assumes any liability with respect to the use of, or damages resulting from the use of, any information, apparatus, method, or process disclosed in this document. Project Manager Craig Schepp Energy Center of Wisconsin Acknowledgements This publication was funded in whole or in part by the State of Wisconsin, Wisconsin Department of Administration, Division of Energy, and was funded through the Focus on Energy program. We would like to acknowledge the following: Chip Bircher, Wisconsin Public Service, for his assistance with the Teachers workshop Steve Bower, Waunakee High School Jim Brown, Nicolet Technical College Bill Cora, Zimpro Division of U.S. Filter Deborah Engel-Di Mauro, University of Wisconsin Stephens Point Tehri Parker, Midwest Renewable Energy Association, for their assistance with the renewable hydrogen demonstrations Craig Schepp, The Energy Center of Wisconsin Don Wichert, Wisconsin Division of Energy, for their assistance with contacting demonstration organizers.

4 Contents Abstract...i Report Summary...iii Introduction...1 Method...5 Results...7 Discussion...9 Nicolet Technical College...9 High School Envrionmental Action Conference...10 Zimpro Division of US Filter...10 Southern Wisconsin High School Science Teachers & Waunakee High School Science Students...10 Teachers Workshop...11 References...13

5 Figures Figure 1. The transition from solid to liquid to gaseous fuel...2 Figure 2. The hydrogen to carbon ratio and the transition to the Hydrogen Economy...2 Figure 3. Actual and projected usage in US of primary fuels over time...3 Figure 4. Schematic of the ACR process...5 Figure 5. Reaction pathways for production of H 2 and alkanes from reactions of carbohydrates with water on metal catalysts. (x=1 and x=0 correspond to C OH and C=O groups, respectively; * represents a surface metal site).6 Figure 6: The renewable glycerol to hydrogen demonstration unit....7 Figure 7. HOPE curriculum, videos, and CD Rom...8 Figure 8. First public demonstration at Nicolet Technical College....9

6 Abstract The purpose of this project was to increase awareness and knowledge of renewable biomass-to-hydrogen energy conversion technology in Wisconsin. This was accomplished through the demonstration and presentation of a renewable hydrogen production technology and by a teacher s workshop introducing a hydrogen curriculum supplement. The project was funded by the Wisconsin Focus on Energy Pilot through the Energy Center of Wisconsin. The U.S. Department of Energy s Biobased Products and Bioenergy Roadmap calls for increasing the use of biobased products and bioenergy in the U.S. 3-fold over 2000 levels by the year By 2020 the Roadmap calls for increasing the use of biobased products and bioenergy in the U.S. by 10-fold over 2000 levels. At this level biomass would account for 25 percent of our nation s total energy and help create the foundation for a secure energy future. Virent Energy Systems (Virent) is developing a new technology called aqueous-phase carbohydrate reforming (ACR) that is capable of converting renewable, biomass based feedstocks to hydrogen. The first objective of this project was to use the ACR technology to demonstrate renewable hydrogen and electricity production in Wisconsin. To meet this objective we built a portable renewable hydrogen generation system, which was demonstrated in December of The second objective of this project was to provide educational materials on hydrogen energy and instructions on their use to Wisconsin teachers. We met the second objective by purchasing 10 sets of hydrogen energy curriculum and scheduling a teacher s workshop in March 2003 to train teachers. i

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8 Report Summary Wisconsin possesses significant amounts of biomass that could be used to produce renewable hydrogen. The Energy Center of Wisconsin (The Center) contracted with Virent Energy Systems (Virent) to build awareness and knowledge of renewable biomass-to-hydrogen energy conversion technology in Wisconsin. We accomplished this by demonstrating and presenting a new renewable hydrogen production technology and by arranging a teacher s workshop introducing a hydrogen curriculum supplement. The Virent technology was developed at the University of Wisconsin-Madison and is discussed in the August 29, 2002 issue of the journal Nature [1]. The U.S. Department of Energy Biobased Products and Bioenergy Roadmap [2] calls for increasing the use of biobased products and bioenergy in the U.S. by 3-fold over 2000 levels by the year By 2020 the Roadmap calls for increasing the use of biobased products and bioenergy in the U.S. by 10-fold over 2000 levels. At this level biomass would account for 25 percent of our nation s total energy and help create the foundation for a secure energy future. Virent is commercializing a new catalytic process that allows the generation of hydrogen and/or hydrocarbon fuel gases via liquid-phase reforming of oxygenated compounds, including renewable biomass-derived sugars and sugar alcohols. This novel aqueous-phase carbohydrate reforming (ACR) process can generate hydrogen (H 2 ), which is a fuel source for fuel cells, internal combustion engines (ICEs), gas turbines, as well as being a commodity chemical. In addition, the ACR process is configurable to generate hydrocarbon fuel gases consisting of a mixture of methane, propane, butane, and hexane. These fuel gases are clean fuel sources for ICEs and turbines. The ACR process opens up an entirely new route for renewable fuel gas generation. The first objective of this project was to use the ACR technology to demonstrate renewable hydrogen and electricity production. This objective was met by building a portable ACR reactor system that converted glycerol into hydrogen. Glycerol is a byproduct of bio-diesel production and is therefore a renewable bio-product. The hydrogen produced by the ACR reactor system was then fed into a proton exchange membrane (PEM) fuel cell to produce electricity. The electricity powered a small electric motor. This unit was demonstrated at three sites in the pilot program area in December of The demonstrations were held at: 1. Nicolet Technical College, Rhinelander, on 12/3/02 2. High School Environmental Action Conference, Stevens Point, on 12/11/02 3. Zimpro Division of U.S. Filter, Rothschild, on 12/12/02 The second objective of this project was to provide educational materials on hydrogen energy and instructions on their use to Wisconsin teachers. We met the second objective by purchasing 10 sets of the Hydrogen Outreach Program for Education (HOPE) curriculum and scheduling a teacher s workshop in March 2003 at the Wisconsin Public Service Corporation s (WPS) SolarWise conference to train teachers to use the curriculum. The HOPE curriculum was developed to teach secondary school students about the potential and benefits of hydrogen as a fuel. The curriculum uses hydrogen topics to teach chemistry. Relevant topics in physics, biology, earth and life sciences, and environmental science are also included. iii

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10 Introduction Because water vapor is the only emission when hydrogen is burned as a fuel, hydrogen holds great promise as a future green energy source. However, while hydrogen itself is an environmentally friendly fuel, current industrial methods for making hydrogen consume non-renewable hydrocarbons (e.g. methane) and produce significant amounts of polluting emissions (e.g. carbon dioxide). These processes also require several reaction steps in separate reactors, use flammable starting materials and take place at high temperatures. Virent has developed a method to generate hydrogen fuel through low-temperature, aqueous-phase catalytic reforming of oxygenated hydrocarbons, such as glucose, xylose, sorbitol, xylitol, glycerol, and ethylene glycol. Unlike conventional starting materials for hydrogen production, which come from natural gas, these oxygenated hydrocarbons can be derived from renewable resources, like plant biomass. Moreover, although the Virent method also produces carbon dioxide as a byproduct, the use of plant biomass as a feed stock should make the net process greenhouse gas emissions neutral. This is because the biomass grown for next year s hydrogen production will fix and store the carbon dioxide released this year. Virent s method of aqueous-phase carbohydrate reforming (ACR) takes advantage of the unique thermodynamic properties of oxygenated compounds containing a C:O stoichiometry of 1:1 that allow complete conversion to H 2 and CO 2 at reaction temperatures less than 260 o C. At these conditions the ACR process generates hydrogen without the need to volatilize water, which represents a major energy savings compared to conventional, vapor-phase, steamreforming processes. In addition, the ACR process occurs at temperatures where the water-gas shift reaction is favorable for low CO concentrations, making it possible to generate PEM fuel cell-grade hydrogen utilizing a single chemical reactor. Furthermore, oxygenated hydrocarbons derived from carbohydrates are nonflammable as well as non-toxic, allowing them to be safe, transportable fuels. The heterogeneous catalysts utilized in the ACR process are expected to be effective for processing any watersoluble sugar or sugar alcohols, regardless of carbon number and stereoisomer. Accordingly, it is expected that this process will be able to produce hydrogen from a single sugar or a mixture of sugars. Accordingly, we expect to be able to process carbohydrates from a large range of biomass, including biomass waste streams as well as high starch content crops. Recently, a joint technical report to the U.S. Department of Agriculture and the U.S. Department of Energy outlined the following benefits of biobased products and bioenergy [see Enhance national energy security. As a domestic energy source, bioenergy can substantially reduce our nation s dependence on imported oil. Improved environmental protection. Bioenergy improves the environment by offsetting fossil fuel use and related emissions of carbon dioxide, nitrogen oxides, sulfur dioxides, and other pollutants. Rural economic growth. Growth in biobased products and bioenergy will stimulate rural development efforts in farming, forestry, and associated service industries. Sustainable global development. Currently, around 100 billion tons of biomass are created worldwide each year, with an energy value five times the total global energy consumption. Proper biomass utilization could provide sustainable development for nations around the world. 1

11 Renewable Hydrogen Demonstration As this list shows, the benefits of biobased products and bioenergy are broad and far-reaching. As Figure 1 shows, the economy is expected to shift from non-sustainable economic growth based on solid and liquid fuels, to increasingly sustainable economic growth based on gaseous fuels. Figure 1. The expected transition from solid to liquid to gaseous fuel in the economy Another view of the same basic shift is provided in Figure 2, which shows the increasing ratio of hydrogen to carbon in the total fuel supply. Figure 2. The hydrogen-to-carbon ratio and the transition to the Hydrogen Economy 2

12 Introduction The right side of Figure 2 shows the transition to hydrogen as the primary global fuel. This is often referred to as the transition to the hydrogen economy. A final view showing actual consumption and projections for the primary fuels is shown in Figure 3. Figure 3. Actual and projected usage of primary fuel in the U.S. As the above figures show, hydrogen and biomass are both expected to play a significant role in future energy systems in Wisconsin, the United States and the world. 3

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14 Method Figure 4 below shows schematically how the ACR process converts biomass to hydrogen. First the biomass is harvested and the carbohydrates are extracted. A solution of water and carbohydrates is then fed to the ACR process where it is converted to hydrogen and carbon dioxide. The hydrogen can be used in fuel cells, internal combustion engines or chemical processing. The carbon dioxide is released to the atmosphere and consumed by the next year s biomass growth. Figure 4. Schematic of the ACR process Recycle of Carbon Dioxide For Biomass Growth Product Markets Biomass Harvest Extraction Process Recycle of Nutrients and Byproducts Aqueous-Phase Carbohydrates ACR Process Hydrogen Fuel Cells IC Engines Turbines Chemical Processing The ACR process takes advantage of the unique thermodynamic properties of oxygenated compounds having a carbon to oxygen (C:O) ratio of one to one (1:1) that allow complete conversion to gaseous hydrogen and/or hydrocarbons and carbon dioxide (CO 2 ), a neutral by-product, at reaction temperatures near 200 C. At a basic level, the process was implemented in the demonstration unit in the following manner: 1. A solution of water and an oxygenated compound (glycerol) is stored in a tank. 2. The liquid feedstock is pumped into the ACR reactor vessel, which contains the appropriate catalyst. 3. The feedstock undergoes both the reforming and water-gas shift reactions in the single reactor vessel, generating gaseous hydrogen and CO 2. 5

15 Renewable Hydrogen Demonstration 4. The hydrogen is separated from the liquid water in a simple phase separator. For hydrogen production the carbon monoxide (CO) content of the gas exiting the single reactor is below 300 ppm, the current detection limit of our CO monitor. 5. The hydrogen is sent to a fuel cell. 6. The CO 2 is absorbed in an absorber bed. CO 2 from biomass feedstock is part of a sustainable cycle and does not increase global CO 2 emissions because it is consumed by the next year s plant growth. The key breakthrough is the fact that the reforming is done in the liquid phase. Two collateral features of this liquidphase reforming are that only a single reactor vessel is needed and that, in hydrogen production, extremely low CO concentrations are obtained. Figure 5 shows a schematic representation of reaction pathways that we suggest are involved in the formation of H 2 and/or alkanes (hydrocarbons) from oxygenated hydrocarbons (shown as carbohydrates) over a metal catalyst. These are the reactions which occur within the ACR reactor. The carbohydrate first undergoes dehydrogenation steps to give adsorbed intermediates, prior to cleavage of C-C or C-O bonds. Subsequent cleavage of C-C bonds leads to the formation of CO and H 2, and CO reacts with water to form CO 2 and H 2 by the water-gas shift (WGS) reaction (i.e., CO + H 2 O CO 2 + H 2 ) [3,4]. The further reaction of CO and/or CO 2 with H 2 (e.g., on metals such as Ni and Ru) leads to alkanes (hydrocarbons) and water by methanation and Fischer-Tropsch reactions [5-7]. In addition, it is possible to form alkanes on the metal catalyst by first cleaving C-O bonds in adsorbed carbohydrate intermediates, followed by the hydrogenation of the resulting adsorbed C n H x species. Figure 5. Reaction pathways for production of H 2 and alkanes from reactions of carbohydrates with water on metal catalysts (x=1 and x=0 correspond to C OH and C=O groups, respectively; * represents a surface metal site) H H O O C C ] H H [ n H 2 H 2 O H H 2 C C * * H H x O C C * * OH x H x O C C-C cleavage C * * * * OH x H 2 CO,H 2 H 2 O WGS CO 2,H 2 6 alkanes H 2 O

16 Results Using the ACR technology, Virent designed and built a portable hydrogen generation system which converted glycerol into hydrogen. Glycerol is a byproduct of bio-diesel production and is therefore a renewable bio-product. The hydrogen produced by the ACR reactor system was then fed into a proton exchange membrane (PEM) fuel cell to produce electricity. The electricity powered a small electric motor. A picture of the demonstration unit is shown in Figure 6 below. Figure 6: The renewable glycerol-to-hydrogen demonstration unit 7

17 Renewable Hydrogen Demonstration The above unit was demonstrated at three sites in the pilot program area in December of The demonstrations were held at: 1. Nicolet Technical College, Rhinelander, on 12/3/02 2. High School Environmental Action Conference, Stevens Point, on 12/11/02 3. Zimpro Division of U.S. Filter, Rothschild, on 12/12/02 The second objective of this project was to provide educational materials on hydrogen energy and instructions on their use to Wisconsin teachers. We met the second objective by purchasing 10 sets of the Hydrogen Outreach Program for Education (HOPE) curriculum and scheduling a teacher s workshop in March 2003 at the Wisconsin Public Service (WPS) Solar Wise conference to train teachers to use the curriculum. The HOPE curriculum was developed to teach secondary school students about the potential and benefits of hydrogen as a fuel. The curriculum uses hydrogen topics to teach chemistry. The HOPE curriculum and accompanying videos and CD are show in Figure 7 below. Figure 7. HOPE curriculum, videos, and CD Rom 8

18 Discussion We conducted three demonstrations of the new Virent ACR hydrogen manufacturing process in northeast Wisconsin. Following are brief descriptions of those demonstrations. Nicolet Technical College Virent was invited to demonstrate the ACR process as part of the Nicolet workshop on renewable energy. Nicolet has an active renewable energy programs involving wind and solar power. The workshop included descriptions of these programs as well as a local solar project in a private home. The Virent mobile demonstration unit was set up and operated in the workshop room. The demonstration unit produced hydrogen, and a fuel cell-powered electric motor was operated on that hydrogen. We delivered a 45- minute PowerPoint slide presentation that covered the application of fuel cells to power generation, the status of the fuel cell industry, the Virent ACR hydrogen production technology, and the status of the company. We answered questions on many aspects of the presentation. This was the first public demonstration of the ACR process. A picture taken at this event is shown in Figure 8. Figure 8. First public demonstration of the ACR unit at Nicolet Technical College 9

19 Renewable Hydrogen Demonstration High School Envrionmental Action Conference Virent was invited to participate in this conference which hosted 285 high school students from around Wisconsin in cooperation with the Midwest Renewable Energy Association. The Virent ACR mobile demonstration unit was set up in the main meeting hall along with the displays from other organizations. Hydrogen produced by the demonstration unit was used to run a fuel cell-powered electric motor. A poster board display showed the ACR process chemistry, its advantages and potential applications. The students and their teachers viewed the demonstration during registration, break and lunch periods. The process operated continuously for about seven hours. MREA conducted a 15-minute presentation at a renewable energy break-out session. The MREA personnel presented information on wind and solar renewable energy systems. The presentation also described the potential of fuel cells and the Virent ACR renewable hydrogen generation process. Many questions were answered. About 30 students and teachers attended. Zimpro Division of US Filter Virent Energy Systems personnel visited Zimpro in Rothchild, Wisconsin to discuss potential common interests in the development and implementation of the ACR process. Zimpro specializes in equipment for the processing of municipal and industrial wastes by air oxidation. They are familiar with many waste streams that might be feedstocks for the Virent ACR process. They also have an extensive pilot plant that could prepare selected waste streams for use in the Virent ACR process. The Virent ACR demonstration unit was set up in the Zimpro conference room and the hydrogen produced by it was used to run the fuel cell-powered electric motor. We described the operation and potential of the ACR process and explored potential synergies with Zimpro s capabilities. Southern Wisconsin High School Science Teachers & Waunakee High School Science Students The presentation was not directly a part of the Focus on Energy Pilot contract. It was done by Virent at its own expense using the demonstration unit. Waunakee High School teacher Steve Bower is very active in teaching fuel cell and renewable energy concepts and is active in the Southern Wisconsin High School Teachers group. Since we wanted to encourage education in fuel cells and hydrogen we offered to conduct a workshop on these topics. High school science teachers from southern Wisconsin and students from Waunakee High School attended. Attendance was about 30 people. The Virent ACR mobile unit was operated as at the other demonstrations, and fuel cells owned by Waunakee HS were also demonstrated. We gave two 30-minute presentations, one on fuel cells and the other on the Virent ACR process. Many questions were answered. 10

20 Discussion Teachers Workshop We determined that the most suitable forum for the teachers workshop was the SolarWise workshop in Green Bay hosted by Wisconsin Public Service Corporation (WPS) in March of We have confirmed arrangements with Chip Bircher of WPS for M.R.S. Enterprises to conduct the workshop. Ten copies of the HOPE curriculum have been sent to WPS for the event. HOPE Pilot tm was developed to teach secondary school students about the potential and benefits of hydrogen as a fuel. The curriculum is intended to supplement existing instructional materials. The curriculum involves plenty of fun-filled, hands-on activities for secondary school education. It includes over 75 lessons with labs, exercises, and demonstrations. The curriculum highlights the role of environmentally friendly hydrogen technologies, notably fuel cell technology. The complete HOPE package consists of the curriculum, four videos and a CD ROM. The curriculum uses hydrogen topics to teach chemistry. Relevant topics in physics, biology, earth and life sciences as well as environmental science, are also included. In addition, the lesson activities are designed to reinforce mathematics. All learning is keyed to both national and state science standards. Content and approach reflect current science education practices. HOPE is an integrated student/teacher curriculum organized into modules that consist of multiple lessons. The lessons provide guidance to the teacher. They include student activities and student assessment material. The curriculum contains seven modules: 1. Fundamentals 2. Production 3. Storage 4. Distribution and Safety 5. Utilization 6. Renewables & Renewable Hydrogen 7. CD Rom Scavenger Hunts The curriculum also includes a final project the HOPE Hydrogen Fueling Station Project. 11

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22 References 1. R.D. Cortright, R.R. Divada, J.A. Dumesic, Nature 418, (2002). 2. Biobased Products and Bioenergy Roadmap, Framework for a Vital New U.S. Industry, Draft 7/18/ Grenoble, D. C., Estadt, M. M. & Ollis, D. F., Journal of Catalysis 67, (1981). 4. Hilaire, S., Wang, X., Luo, T., Gorte, R. J. & Wagner, J., Applied Catalysis, A 215, (2001). 5. Iglesia, E., Soled, S. L. & Fiato, R. A., Journal of Catalysis 137, (1992). 6. Kellner, C. S. & Bell, A. T., Journal of Catalysis 70, (1981). 7. Vannice, M. A., Journal of Catalysis 50, (1977). 13

23 ENERGY CENTER OF WISCONSIN 595 Science Drive Madison, WI Phone: Fax: Printed on Plainfield Plus, a recycled chlorine-free stock containing 20% post-consumer waste.