The U.S. Department of Energy/Federal Energy Technology Center (DOE/FETC)-sponsored High Performance Power Systems (HIPPS) program headed by United Technologies Research Center has identified coal-based combined-cycle power systems using advanced technology gas turbines that could operate at efficiencies approaching 55% (HHV). The HIPPS uses a High Temperature Advanced Furnace (HITAF) to preheat combustion turbine air. The HITAF’s metallic air heaters include a radiator section located in the furnace slagging zone and a convection section located in the downstream portion. The compressor discharge air is heated to 925 C – 1150 C. Additional heat for the turbine, if required in the cycle, is added by special low-NOx gas-fired combustors. The HITAF design has been successfully tested at the desired temperatures for short durations at the Energy and Environmental Research Center, Grand Forks, ND, with tests continuing to expand the systems experience and capabilities. The HIPPS concept with its HITAF advanced air heater are valuable technology candidates for integration into Vision 21, the DoE’s evolving plan to utilize coal and other fossil fuels in energy complexes producing power, chemicals, process heat and other byproducts. For example, the HIPPS would be combined with high temperature fuel cells, e.g., the solid oxide fuel cell (SOFC), resulting in power systems having overall electrical efficiencies greater than 60% (HHV) with 50% or more of the energy input from coal. These power plants would have near zero emissions with a goal for power costs 10% below current coal-fired systems. Emissions of CO2, an important greenhouse gas, will be drastically reduced by the higher efficiencies of HIPPS cycles. Very important from a power and coproduction market viewpoint, HIPPS can be an attractive repowering technology. This will allow Vision 21 technology to be used in those plants that seek to continue using coal and other alternative solid fuels to capture the economic benefits of their low energy costs. Here, HIPPS adds high efficiency; increased capacity; load following and dispatching flexibility, as well as important environmental benefits to sites having existing fuel and transmission infrastructure.

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We present an update on the development of technologies required for the Zero Emission Carbon (ZEC) concept being pursued by ZECA Corporation. The concept has a highly integrated design involving hydrogasification, a calcium oxide driven reforming step that includes simultaneous C02 separation, coal compatible fuel cells for electricity production and heat recovery, and a closed loop gas system in which coal contaminants are removed either as liquids or solids. The process does not involve any combustion and as such has neither smokestack nor air emissions. An independent assessment of the concept by Nexant, a Bcchtel affiliated company, suggests a net efficiency of approximately 70% for conversion of the higher heat value fuel energy into electrical output. This is even after the penalties of carbon dioxide separation and pressurization to 1000 psi are taken into account. For carbon dioxide sequestration a variety of options are being considered, which include enhanced oil recovery in the nearterm and mineral carbonation as a long-term approach. We report on our early results in the development of sulfur tolerant anode materials for solid oxide fuel cells; a critical analysis of the calcium oxide