Ceramic Gas Turbine Development: Need for a 10Year Plan

Abstract

Ceramic gas turbine development that started in the 1950s has slowed considerably since most of the large-scale ceramic gas turbine development programs of the 1970s–1990s ended. While component durability still does not meet expectations, the prospect of significant energy savings and emission reductions, potentially achievable with ceramic gas turbines, continues to justify development efforts. Four gas turbine applications have been identified that could be commercially attractive: a small recuperated gas turbine (microturbine) with ∼35% electrical efficiency, a recuperated gas turbine for transportation applications with ∼40% electrical efficiency with potential applications for efficient small engine cogeneration, a ∼40% efficient midsize industrial gas turbine, and a ∼63% (combined cycle) efficient utility turbine. Key technologies have been identified to ensure performance and component durability targets can be met over the expected life cycle for these applications. These technologies include a Si3N4 or SiC with high fracture toughness, durable EBCs for Si3N4 and SiC, an effective EBC∕TBC for SiC∕SiC, a durable oxide∕oxide ceramic matrix composite (CMC) with thermally insulating coating, and the next generation CMCs with high strength that can be used as structural materials for turbine components for small engines and for rotating components in engines of various sizes. The programs will require integrated partnerships between government, national laboratories, universities, and industry. The overall cost of the proposed development programs is estimated at U.S. $100M over 10years, i.e., an annual average of U.S. $10M.