Power Dense Bottoming Cycles for Microturbine Energy Recovery Navy SBIR FY2009.1 Sol No.: Navy SBIR FY2009.1 Topic No.: N091-072 Topic Title: Power Dense Bottoming Cycles for Microturbine Energy Recovery Proposal No.: N091-072-0824 Firm: TIAX LLC 15 Acorn Park Cambridge, Massachusetts 02140 Contact: John Dieckmann Phone: (617) 498-5818 Web Site: http://www.TIAXLLC.com Abstract: TIAX LLC proposes to develop an organic Rankine bottoming cycle utilizing a scroll expander with HFC-245fa working fluid, which will use the waste heat content from the exhaust from a microturbine to generate additional elecric power. The scroll expander provides high efficiency at both on and off design conditions and at full and part load conditions. THe design of the scroll expander is a derivative of the existing TIAX carbon dioxide expander technology. HFC-245fa is a benign, readily available working fluid whose thermodynamic properties allow a large amount of the heat content of the microturbine exhaust to be utilized. The proposed scroll expander technology is also applicable to bottoming cycles for heavy duty truck engines, where the expander would be mechanically connected to the engine shaft via the accessory belt drive. Benefits: Technically and commercially viable exhaust gas driven bottoming cycles will improve the efficiency of a variety of prime movers, microturbines and heavy duty truck engines being two prime examples. Efficiency improvements on the order of 25 to 30% are possible with microturbines. With this increased efficiency level, microturbines will be able to provide electric power at better efficiency than the electric grid, while reducing the load on the grid at the sametime. Fuel mileage improvements on the order of 10 to 15% are possible for long haul trucking. The proposed scroll expander can be easily connected to the truck engine via the accessory belt drive Return