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At least 1,423 records · Page 79

A Community-Based Approach to Leading the Nation in Smart Energy Use

Project Objectives The AEP Ohio gridSMART® Demonstration Project (Project) achieved the following objectives: • Built a secure, interoperable, and integrated smart grid infrastructure in northeast central Ohio that demonstrated the ability to maximize distribution system efficiency and reliability and consumer use of demand response programs that reduced energy consumption, peak demand, and fossil fuel emissions. • Actively attracted, educated, enlisted, and retained consumers in innovative business models that provided tools and information reducing consumption and peak demand. • Provided the U.S. Department of Energy (DOE) information to evaluate technologies and preferred smart grid business models to be extended nationally. Project Description Ohio Power Company (the surviving company of a merger with Columbus Southern Power Company), doing business as AEP Ohio (AEP Ohio), took a community-based approach and incorporated a full suite of advanced smart grid technologies for 110,000 consumers in an area selected for its concentration and diversity of distribution infrastructure and consumers. It was organized and aligned around: • Technology, implementation, and operations • Consumer and stakeholder acceptance • Data management and benefit assessment Combined, these functional areas served as the foundation of the Project to integrate commercially available products, innovative technologies, and new consumer products and services within a secure two-way communication network between the utility and consumers. The Project included Advanced Metering Infrastructure (AMI), Distribution Management System (DMS), Distribution Automation Circuit Reconfiguration (DACR), Volt VAR Optimization (VVO), and Consumer Programs (CP). These technologies were combined with two-way consumer communication and information sharing, demand response, dynamic pricing, and consumer products, such as plug-in electric vehicles and smart appliances. In addition, the Project incorporated comprehensive cyber security capabilities, interoperability, and a data assessment that, with grid simulation capabilities, made the demonstration results an adaptable, integrated solution for AEP Ohio and the nation.

24 POWER TRANSMISSION AND DISTRIBUTION↗

ARPA-E / Achieving at 10,000 GPU Permeance for Post-Combustion Carbon Capture with Gelled Ionic Liquid-Based Membranes

Carbon dioxide (CO 2 ) makes up 78% of anthropogenic greenhouse gas production and has been linked to global climate change and ocean acidification. Therefore, as climate change becomes an increasingly unavoidable environmental, industrial, and political issue, it is desirable to develop technology capable of economically separating and sequestering large amounts of CO 2 . This separation and sequestration technology is also likely to play a role in maintaining the economic value of fossil fuels in the event of a concerted global CO 2 mitigation effort. The initial step toward this technology is to identify and develop an economically viable method of separating CO 2 from flue gas at large point sources such as coal-fired power plants. As an alternate CO 2 capture technology, polymer-based membrane separations offer relatively low operating costs with low-maintenance requirements. Therefore, the development of highly selective and permeable membranes for the separation and ultimate sequestration of CO 2 is of vital importance.

36 MATERIALS SCIENCE↗

New Hampshire Better Buildings - Final Report

With $10 million in funding from the U.S. Department of Energy's (DOE) Better Buildings Neighborhood Program, the NH Better Buildings program was established as an initiative that initially empowered the three “Beacon Communities” of Berlin, Nashua and Plymouth to achieve transformative energy savings and reductions in fossil fuel use and greenhouse gases through deep energy retrofits and complementary sustainable energy solutions. The program also enabled those Communities to provide leadership to other communities around the state as “beacons” of energy efficiency. The goal of the program was to reduce energy use by a minimum of 15% through energy efficiency upgrades in residential and commercial buildings in the communities. The program expanded statewide in April 2012 by issuing a competitive solicitation for additional commercial projects non-profit, and municipal energy efficiency projects from any community in the state, and a partnership with the state’s utility-run, ratepayer-funded residential Home Performance with ENERGY STAR® (HPwES) program. The NH Better Buildings program was administered by the New Hampshire Office of Energy and Planning (OEP) and managed by the NH Community Development Finance Authority (CDFA). The program started in July 2010 and the last projects funded with American Reinvestment and Recovery Act (ARRA) funds were completed in August 2013. The program will continue after the American Recovery and Reinvestment Act program period as a Revolving Loan Fund, enabling low-interest financing for deep energy retrofits into the future.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Nanoscaled Components for Improved Efficiency in a Multiplanel Photocatalytic Water-Splitting System

The goal of this program was to construct a multicell photochemical device for the direct conversion of solar energy directly to hydrogen by water splitting. We have fabricated a practical photolytic system for quantum efficient production of hydrogen. Our approach is based on the assembly of a multi-component integrated system for direct photocatalytic splitting of water for the efficient production of hydrogen. We propose to produce hydrogen as an energy source that is cost competitive with fossil fuels and without the concomitant production of greenhouse gases. The concept is quite straightforward. In order to achieve the over potential required for direct water splitting, the device is composed of multiple dye-sensitized cells directly linked in series, as illustrated in the figure below. The advantage of this concept is that each cell need contribute only a fraction of the overall potential required for water splitting, thus permitting device engineering to maximized efficiently without regard to electric potential. Progress and barriers to practical application will be described.

14 SOLAR ENERGY↗

Potential for the Use of Energy Savings Performance Contracts to Reduce Energy Consumption and Provide Energy and Cost Savings in Non-Building Applications

The findings of this study indicate that potential exists in non-building applications to save energy and costs. This potential could save billions of federal dollars, reduce reliance on fossil fuels, increase energy independence and security, and reduce greenhouse gas emissions. The Federal Government has nearly twenty years of experience with achieving similar energy cost reductions, and letting the energy costs savings pay for themselves, by applying energy savings performance contracts (ESPC) in its buildings. Currently, the application of ESPCs is limited by statute to federal buildings. This study indicates that ESPCs can be a compatible and effective contracting tool for achieving savings in non-building applications.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Geological Sequestration Training and Research Program in Capture and Transport: Development of the Most Economical Separation Method for CO2 Capture

The project provided hands-on training and networking opportunities to undergraduate students in the area of carbon dioxide (CO2) capture and transport, through fundamental research study focused on advanced separation methods that can be applied to the capture of CO2 resulting from the combustion of fossil-fuels for power generation . The project team’s approach to achieve its objectives was to leverage existing Carbon Capture and Storage (CCS) course materials and teaching methods to create and implement an annual CCS short course for the Tuskegee University community; conduct a survey of CO2 separation and capture methods; utilize data to verify and develop computer models for CO2 capture and build CCS networks and hands-on training experiences. The objectives accomplished as a result of this project were: (1) A comprehensive survey of CO2 capture methods was conducted and mathematical models were developed to compare the potential economics of the different methods based on the total cost per year per unit of CO2 avoidance; and (2) Training was provided to introduce the latest CO2 capture technologies and deployment issues to the university community.

Vahdat, Nader↗

Genetics and Molecular Biology of Hydrogen Metabolism in Sulfate-Reducing Bacteria

The degradation of our environment and the depletion of fossil fuels make the exploration of alternative fuels evermore imperative. Among the alternatives is biohydrogen which has high energy content by weight and produces only water when combusted. Considerable effort is being expended to develop photosynthetic systems -- algae, cyanobacteria, and anaerobic phototrophs -- for sustainable H 2 production. While promising, this approach also has hurdles such as the harvesting of light in densely pigmented cultures that requires costly constant mixing and large areas for exposure to sunlight. Little attention is given to fermentative H 2 generation. Thus understanding the microbial pathways to H 2 evolution and metabolic processes competing for electrons is an essential foundation that may expand the variety of fuels that can be generated or provide alternative substrates for fine chemical production. We studied a widely found soil anaerobe of the class Deltaproteobacteria, a sulfate-reducing bacterium to determine the electron pathways used during the oxidation of substrates and the potential for hydrogen production.

08 HYDROGEN↗

Agua Caliente Wind/Solar Project at Whitewater Ranch

Agua Caliente Band of Cahuilla Indians (ACBCI) was awarded a grant by the Department of Energy (DOE) to study the feasibility of a wind and/or solar renewable energy project at the Whitewater Ranch (WWR) property of ACBCI. Red Mountain Energy Partners (RMEP) was engaged to conduct the study. The ACBCI tribal lands in the Coachella Valley have very rich renewable energy resources. The tribe has undertaken several studies to more fully understand the options available to them if they were to move forward with one or more renewable energy projects. With respect to the resources, the WWR property clearly has excellent wind and solar resources. The DOE National Renewable Energy Laboratory (NREL) has continued to upgrade and refine their library of resource maps. The newer, more precise maps quantify the resources as among the best in the world. The wind and solar technology available for deployment is also being improved. Both are reducing their costs to the point of being at or below the costs of fossil fuels. Technologies for energy storage and microgrids are also improving quickly and present additional ways to increase the wind and/or solar energy retained for later use with the network management flexibility to provide power to the appropriate locations when needed. As a result, renewable resources continue to gain more market share. The transitioning to renewables as the major resources for power will take some time as the conversion is complex and can have negative impacts if not managed well. While the economics for wind and solar systems continue to improve, the robustness of the WWR site was validated by the repeated queries of developers to place wind and/or solar there. The robust resources and improving technologies portends toward WWR land as a renewable energy site. The business case, however, is not so clear, especially when the potential investment portfolio for ACBCI has several very beneficial and profitable alternatives.

17 WIND ENERGY↗

Water Use in Enhanced Geothermal Systems (EGS): Geology of U.S. Stimulation Projects, Water Costs, and Alternative Water Source Policies

According to the Energy Information Administration (EIA) of the U.S. Department of Energy (DOE), geothermal energy generation in the United States is projected to more than triple by 2040 (EIA 2013). This addition, which translates to more than 5 GW of generation capacity, is anticipated because of technological advances and an increase in available sources through the continued development of enhanced geothermal systems (EGSs) and low-temperature resources (EIA 2013). Studies have shown that air emissions, water consumption, and land use for geothermal electricity generation have less of an impact than traditional fossil fuel–based electricity generation; however, the long-term sustainability of geothermal power plants can be affected by insufficient replacement of aboveground or belowground operational fluid losses resulting from normal operations (Schroeder et al. 2014). Thus, access to water is therefore critical for increased deployment of EGS technologies and, therefore, growth of the geothermal sector. This paper examines water issues relating to EGS development from a variety of perspectives. It starts by exploring the relationship between EGS site geology, stimulation protocols, and below ground water loss, which is one of the largest drivers of water consumption for EGS projects. It then examines the relative costs of different potential traditional and alternative water sources for EGS. Finally it summarizes specific state policies relevant to the use of alternative water sources for EGS, and finally explores the relationship between EGS site geology, stimulation protocols, and below ground water loss, which is one of the largest drivers of water consumption for EGS projects.

58 GEOSCIENCES↗

Laboratory Studies of the Role of Amines in Particle Formation, Growth and Climate

Organosulfur compounds have a variety of sources, particularly biological processes in the oceans. Their oxidation in air forms sulfur dioxide, which is further oxidized to sulfuric acid, as well as methanesulfonic acid (MSA). While sulfuric acid is a well known precursor to particles in air, MSA had not been regarded as a source of new particle formation. Laboratory studies were carried out under this project that showed MSA forms new particles quite efficiently in the presence of amines and water vapor. The data could be reproduced with a relatively simple kinetics model representing cluster formation and growth, which is promising for representing this chemistry in global climate models. The initial steps in the kinetics scheme are based on quantum chemical calculations of likely clusters. The organosulfur chemistry was introduced into an atmospheric model for southern California and used to predict the impact of going to a fossil-fuel free world in which anthropogenic emissions of SO 2 are removed, but the natural processes remain.

54 ENVIRONMENTAL SCIENCES↗

PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems

These funds were used for partial support of the PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems, that was held on 8-11 August, 2013, at Washington University, St. Louis, MO. This conference, held in conjunction with the 16th International Congress on Photosynthesis/St. Louis, continued a long tradition of light-harvesting satellite conferences that have been held prior to the previous six international photosynthesis congresses. In this Workshop, the basis was explored for the current interest in replacing fossil fuels with energy sources derived form direct solar radiation, coupled with light-driven electron transport in natural photosynthetic systems and how they offer a valuable blueprint for conversion of sunlight to useful energy forms. This was accomplished through sessions on the initial light-harvesting events in the biological conversion of solar energy to chemically stored energy forms, and how these natural photosynthetic processes serve as a guide to the development of robust bio-hybrid and artificial systems for solar energy conversion into both electricity or chemical fuels. Organized similar to a Gordon Research Conference, a lively, informal and collegial setting was established, highlighting the exchange of exciting new data and unpublished results from ongoing studies. A significant amount of time was set aside for open discussion and interactive poster sessions, with a special session devoted to oral presentations by talented students and postdoctoral fellows judged to have the best posters. This area of research has seen exceptionally rapid progress in recent years, with the availability of a number of antenna protein structures at atomic resolution, elucidation of the molecular surface architecture of native photosynthetic membranes by atomic force microscopy and the maturing of ultrafast spectroscopic and molecular biological techniques for the investigation and manipulation of photosynthetic systems. The conferees represented a diverse international and multidisciplinary group, with over 160 individuals attending from a total of 17 different countries. Attendees came from a wide range of fields assuring that the widest possible interdisciplinary exchanges. They included prominent biochemists, biophysicists, plant physiologists, chemical physicists, as well as theoretical and computational physical chemists, who presented their research findings or to hear the latest advances in this very dynamic field. In the choice of speakers, a balance was created between established scientists and young, emerging researchers, given this opportunity to showcase their results. Sessions were held on electronic and vibrational coherence including coherent sharing of excitations among donor and acceptor molecules during excitation energy transfer, nonphotochemical quenching, acclimation to light environments, evolution, adaptation and biodiversity of light-harvesting pigment-protein complexes, their structure and membrane organization, spectroscopy and dynamics, as well as artificial antenna systems. A joint session was also held with the participants from the Cyanobacterial Satellite Conference. A special issue of Photosynthesis Research devoted to light harvesting (Volume 121, Issue No. 1, July 2014) has recently appeared which contains peer-reviewed original research contributions arising from talks and posters presented at the PS2013 Satellite Workshop on Photosynthetic Light-Harvesting Systems. Edited by the Organizers of the Workshop, Robert E. Blankenship, Harry A. Frank and Robert A. Niederman, it includes topics ranging from the isolation of new bacteriochlorophyll species from green bacteria, temperature effects on the excited states of the newly discovered chlorophyll (Chl) ƒ, new architectures for enhancing energy capture by biohybrid light-harvesting complexes, forces governing the formation of light-harvesting rings, spectroscopy of carotenoids of algae and diatoms and the supramolecular organization of caroteno-Chl proteins in diatoms, the molecular basis for urea dissociation of phycocyanin trimers and the role of vibronic molecular excitation theory in describing the spectral dynamics of pigment-protein complexes.

14 SOLAR ENERGY↗

Atomic Scale Imaging of the Electronic Structure and Chemistry of Graphene and Its Precursors on Metal Surfaces

The objectives of this project were to reveal the mechanisms and reaction processes that solid carbon materials undergo when combining with gases such as oxygen, water vapor and hydrocarbons. This research was focused on fundamental chemical events taking place on single carbon sheets of graphene, a two-dimensional, polycyclic carbon material that possesses remarkable chemical and electronic properties. Ultimately, this work is related to the role of these materials in mediating the formation of polycyclic aromatic hydrocarbons (PAH’s), their reactions at interfaces, and the growth of soot particles. Our intent has been to contribute to a fundamental understanding of carbon chemistry and the mechanisms that control the formation of PAH’s, which eventually lead to the growth of undesirable particulates. We expect increased understanding of these basic chemical mechanisms to spur development of techniques for more efficient combustion of fossil fuels and to lead to a concomitant reduction in the production of undesirable solid carbon material.

25 ENERGY STORAGE↗

Achieving a Net Zero Energy Retrofit - In a humid, temperate climate: Lessons from the University of Hawai'i at Manoa

The University of Hawaii at Manoa (UHM) partnered with the US Department of Energy (DOE) to develop and implement solutions to retrofit exiting buildings to reduce energy consumption by at least 30% as part of DOE’s Commercial Building Partnerships (CBP) Program.1 Kuykendall Hall, located on the UHM campus in Honolulu, was the focus of a CBP analysis and design collaboration among the University of Hawai’i, their consultants, and Lawrence Berkeley National Laboratory (LBNL). Kuykendall Hall consists of two 1960s-era wings – a four-story wing containing classrooms, and a seven-story tower containing offices – with a total floor area of approximately 76,000 square feet (ft2). The retrofit design, which uses local prevailing winds to aid ventilation and cooling and incorporates envelope and lighting elements that reduce the need for cooling, was initially on track to use about 50% less energy than the current building, exceeding the CBP’s 30% savings goal. With the addition of building-mounted solar electric panels, the retrofitted building is projected to achieve net-zero annual energy use. Achieving net-zero energy addressed an emerging challenge to the university – how to lower energy usage and reduce dependence on imported fossil fuel in the face of already-high energy prices that are forecast to double by 2040. Not only will the retrofit dramatically reduce Kuykendall Hall’s annual energy costs, but the project lays the groundwork for new campus policies and processes and low-energy design approaches and is building a campus knowledge base on low-energy practices. This project is a model of integrated design and building delivery that will be replicated in future projects on the campus.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High-T and Dynamic Gas Pressure in Harsh Environments

This is the final report for the program “Micro-Structured Sapphire Fiber Sensors for Simultaneous Measurements of High Temperature and Dynamic Gas Pressure in Harsh Environments”, funded by NETL, and performed by Missouri University of Science and Technology, Clemson University and University of Cincinnati from October 1, 2009 to September 30, 2014. Securing a sustainable energy economy by developing affordable and clean energy from coal and other fossil fuels is a central element to the mission of The U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL). To further this mission, NETL funds research and development of novel sensor technologies that can function under the extreme operating conditions often found in advanced power systems. The main objective of this research program is to conduct fundamental and applied research that will lead to successful development and demonstration of robust, multiplexed, microstructured silica and single-crystal sapphire fiber sensors to be deployed into the hot zones of advanced power and fuel systems for simultaneous measurements of high temperature and gas pressure. The specific objectives of this research program include: 1) Design, fabrication and demonstration of multiplexed, robust silica and sapphire fiber temperature and dynamic gas pressure sensors that can survive and maintain fully operational in high-temperature harsh environments. 2) Development and demonstration of a novel method to demodulate the multiplexed interferograms for simultaneous measurements of temperature and gas pressure in harsh environments. 3) Development and demonstration of novel sapphire fiber cladding and low numerical aperture (NA) excitation techniques to assure high signal integrity and sensor robustness.

01 COAL, LIGNITE, AND PEAT↗

Biomass Resource Demand Characterization Study: Cooperative Research and Development Final Report, CRADA Number CRD-11-436

Competing demands for U.S. biomass resources and resulting impacts on regional feedstock availability could have a significant impact on the ability of the biofuels industry to transition to lower cost feedstocks, such as wood, agricultural residues, and energy crops, as well as on the ability of U.S. electric utilities and consumers to meet Renewable Portfolio Standards (RPS) and transition to lower carbon-footprint sources of electricity. Promulgation of regulations that place a cost on CO2 emissions from fossil fuels will also impact this situation as biomass to power applications become increasingly cost competitive. This increased competition for biomass feedstocks could create technical and economic risks for the Government, industry, and investors, and has the potential to impede commercialization of bio-energy in the U.S. at a meaningful scale.

09 BIOMASS FUELS↗

Conversion of CO 2 into Commercial Materials Using Carbon Feedstocks

In this project, our research focused on developing reaction chemistry that would support using carbon as a reductant for CO 2 utilization that would permit CO 2 consumption on a scale that would match or exceed anthropomorphic CO 2 generation for energy production from fossil fuels. Armed with the knowledge that reactions attempting to produce compounds with an energy content greater than CO 2 would be thermodynamically challenged and/or require significant amounts of energy, we developed a potential process that utilized a solid carbon source and recycled the carbon to effectively provide infinite time for the carbon to react. During testing of different carbon sources, we found a wide range of reaction rates. Biomass-derived samples had the most reactivity and coals and petcoke had the lowest. Because we had anticipated this challenge, we recognized that a catalyst would be necessary to improve reaction rates and conversion. From the data analysis of carbon samples, we recognized that alkali metals improved the reaction rate. Through parametric testing of catalyst formulations we were able to increase the reaction rate with petcoke by a factor of >70. Our efforts to identify the reaction mechanism to assist in improving the catalyst formulation demonstrated that the catalyst was catalyzing the extraction of oxygen from CO 2 and using this extracted oxygen to oxidize carbon. This was a significant discovery in that if we could modify the catalyst formulation to permit controlled the oxidation, we would have a very power selective oxidation process. With selective oxidation, CO 2 utilization could be effective used as one of the process steps in making many of the large volume commodity chemicals that support our modern lifestyles. The key challenges for incorporating these functionalities into the catalyst formulation were to make the oxidation selective and lower the temperature required for catalytic activity. We identified four catalyst families that had the potential to meet these challenges. Initial screening of the catalyst families did show that the reduction/oxidation activity did occur at lower temperatures and that these catalysts were able to cause carbon chain growth as well as C—C cleavage. A preliminary techno-economic feasibility of using petcoke/catalyst to produce a CO-rich syngas product was completed and showed significant economic promise. Testing of the different catalyst families demonstrated that Catalyst A was able to stably produce 5 sccm of ethylene/gram of catalyst at 900°C for one hour. For dry methane reforming, our Catalyst 4 was able to achieve production rates of > 10 sccm of CO and > 3 sccm of H2 per gram of catalyst at 600°C and 350 psig. Based on these developments, the potential for CO 2 utilization in the production of large volume commodity chemicals is very promising.

10 SYNTHETIC FUELS↗

Modular Undersea Compressed Air Energy Storage (UCAES) System

This project has been devoted to the design, optimization, and cost analysis of a unique power plant with integral energy storage. The proposed facility combines a novel underwater compressed air energy storage (UCAES) system with a customized gas turbine generator, providing exceptional power management and overall efficiency. Unlike conventional CAES, opportunities for underwater storage are plentiful and proximal to the power grid. The UCAES system provides coastal and island communities a practical means for managing the volatility of large-scale wind and solar power resources. The result is higher renewable energy absorption and improved electrical reliability with reduced fossil fuel consumption. The UCAES power plant is composed of three major subsystems: The underwater air containment system (ACS), the air transport pipe (ATP), and the land-based power conversion system (PCS). The underwater ACS is made up of modular concrete shell units, structurally optimized for minimal material usage while employing conventional production methods and equipment. Each shell is designed to receive and control loose fill or gravel, serving as the ballast. The static nature of the final structures make them an asset to marine habitats and includes features intended to permit safe and cost-effective deployment. The ATP Connects the ACS modules to each other and to the on-land power conversion system and utilizes high density polyethylene (HDPE) pipe for low cost and long life. The PCS Houses the turbine-generator ‘expander modules’, with peak capacity of 12.3 MWe each, engineered from existing gas turbine equipment and includes electrically driven commercial 3-stage intercooled centrifugal compressors, each nominally drawing 6.6 MWe when matching the turbine flow requirements. The subsystems listed above are designed with the intent to serve as building-blocks to achieve a peak power output rating in the 40 to 120 MWe range, with 0.25 to 4 hours of energy storage capacity. The modular facility with integral energy storage provides some remarkable transient maneuvers and load-following features unachievable by competing technologies. The system can operate as a dispatchable power plant with a fuel-to-electric efficiency over 41%; substantially better that the average existing Hawaiian peak power generation assets. Optimal efficiency can be maintained while load-following due to modular PCS design and is operable with a range of liquid or gaseous fuels while meeting the most stringent California (CARB) emission standards. The system can operate as a peaking energy plant in discharge mode. Power ramp-up equivalent to 215% of continuous load rating within 1 second accomplished by simply turning off the electric compressor(s). Contrarily, the system can offer energy absorption during periods of grid surplus generation. The electric compressors may be sequenced on to absorb power within seconds. More moderate transitions are easily achieved with standard compressor control functions. The system offers unique features as compared to energy storage systems. ‘Round-trip efficiency’, as calculated by industry standard methods, is in the 90% range. The PCS equipment has a mean-time between overhauls of 80,000 hours, with maintenance costs of less than $0.005/kW-hr of electricity delivered. The underwater ACS structures and piping employ materials and designs specified to achieve a 75 year life. With the underwater containment modules qualified as a marine habitat, there would be no decommissioning costs. In conjunction with the engineering work invested in the design of the UCAES power plant, Brayton Energy has employed a team of manufacturing specialists, marine construction engineers, and power industry experts to create a comprehensive economic model that captures the many site-related variables and configuration options. The cost results and methodology have been validated by suppliers, engineers, and deployment specialists through a detailed case study on Hawaii. While creation of the parametric cost model was based on inputs specific to Hawaii, the proposed construction and deployment steps were chosen to be general enough to allow extrapolation across locations world-wide. Analysis of the proposed system shows it to be a viable option and addresses the principal challenges described by the Department of Energy by offering competitive costs, validated safety and reliability, consideration of the regulatory environment, and utilization of industry accepted practices and equipment. The UCAES system is recommended for immediate consideration in Hawaii. Estimation of time to complete planning, design, and construction of the facility is anticipated to take 3 to 5 years. Other coastal and island communities world-wide should realize similar benefits; as the results presented in this report are considered generally transferable to other locations.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Recovery Act: Analysis of Low-Temperature Utilization of Geothermal Resources (Final Technical Report)

Full realization of the potential of what might be considered “low-grade” geothermal resources will require that we examine many more uses for the heat than traditional electricity generation. To demonstrate that geothermal energy truly has the potential to be a national energy source we will be designing, assessing, and evaluating innovative uses for geothermal-produced water such as hybrid biomass-geothermal cogeneration of electricity and district heating and efficiency improvements to the use of cellulosic biomass in addition to utilization of geothermal in district heating for community redevelopment projects. The objectives of this project were: 1) to perform a techno-economic analysis of the integration and utilization potential of low-temperature geothermal sources. Innovative uses of low-enthalpy geothermal water were designed and examined for their ability to offset fossil fuels and decrease CO 2 emissions. 2) To perform process optimizations and economic analyses of processes that can utilize low-temperature geothermal fluids. These processes included electricity generation using biomass and district heating systems. 3) To scale up and generalize the results of three case study locations to develop a regionalized model of the utilization of low-temperature geothermal resources. A national-level, GIS-based, low-temperature geothermal resource supply model was developed and used to develop a series of national supply curves. We performed an in-depth analysis of the low-temperature geothermal resources that dominate the eastern half of the United States. The final products of this study include 17 publications, an updated version of the cost estimation software GEOPHIRES, and direct-use supply curves for low-temperature utilization of geothermal resources. The supply curves for direct use geothermal include utilization from known hydrothermal, undiscovered hydrothermal, and near-hydrothermal EGS resources and presented these results at the Stanford Geothermal Workshop. We also have incorporated our wellbore model into TOUGH2-EGS and began coding TOUGH2-EGS with the wellbore model into GEOPHIRES as a reservoir thermal drawdown option. Additionally, case studies for the WVU and Cornell campuses were performed to assess the potential for district heating and cooling at these two eastern U.S. sites.

15 GEOTHERMAL ENERGY↗