Browsing by Subject "CAES"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Compressed Air Energy Storage (CAES) in Northern Minnesota Using Underground Mine Workings and Above Ground Features(University of Minnesota Duluth, 2015) Fosnacht, Donald R; Wilson, Elizabeth J; Marr, Jeffrey D; Carranza-Torres, Carlos; Hauck, Steven A; Teasley, RebeccaThe goal of this research project is to determine the potential viability, environmental sustainability, and societal benefits of CAES, as a vital, enabling technology for wind turbine based power generation. The intent of this research is to provide a clear roadmap for CAES development in Minnesota. This project is multifaceted and draws resources across the University System and from key industrial partners: Great River Energy and Minnesota Power. The results from the project will provide vital information to decision makers on the potential of CAES and give guidance on how the technology can be implemented using the unique assets of the Minnesota’ various Iron Ranges (Mesabi and Cuyuna) or in other areas, so that renewable mandates and greenhouse gas reduction can be effectively accomplished. The results show that the topography and water resources exist at various sites that could allow a 100 to 200 MW facility to be constructed if the overall economic, mineral rights, and environmental issues associated with a given site can be properly managed. This report delves into the possibilities and outlines selection criteria that can be used for site selection. Other information is developed to compare the potential economic impact of implementation of the project within the constraints of the factors that can be monetized using the current policy environment. Finally, potential life cycle, regulatory, environmental, and permitting issues that are associated with implementation of the concept are discussed.Item Increasing efficiency and power density of a liquid piston air compressor / expander with porous media heat transfer elements(2014-12) Wieberdink, Jacob HenryIn this thesis, a power dense and efficient air compressor/ expander is investigated experimentally. High power density and high efficiency are realized with a quasi-isothermal process, made possible by a liquid piston compressor/ expander and the addition of porous media heat transfer elements. Uniform and non-uniform distributions of porous media are considered and compared with a baseline case.Experiments are conducted using a 2.2 L displacement compressor/ expander. Air is compressed from 7 bar to 210 bar in compression tests and expanded from 210 bar to 7 bar in expansion tests. Baseline compression times vary from 2s to 400s and compression power density varies from 4 kW/m3 to 600 kW/m3. Baseline expansion times vary from 1s to 400s and expansion power density varies from 4 kW/m3 to 2 MW/m3. The baseline compression experiments covered. This study finds that as power density increases, efficiency decreases. At 90% efficiency, a moderate amount of porous media (uniform distribution of 76% porosity) improves compression power density by a factor of 10 and expansion efficiency by a factor of 17. Further improvements are possible with an optimized porous medium geometry.These results have implications for many applications where efficient gas compression/expansion is required including: compressed air for energy storage at scales that range from residential-scale to grid-scale, pneumatics, compressed industrial gasses, and compressed gaseous fuels like hydrogen and natural gas. Quasi-isothermal compression and expansion also enables the realization of thermodynamic cycles that require isothermal compression or expansion.