Preparing for the Future: Reducing Gas Turbine Environmental Impact

Abstract

In the long term the price of fuel will rise and it is now urgent to reduce carbon dioxide emissions to avoid catastrophic climate change. This lecture looks at power plant for electricity generation and aircraft propulsion, considering likely limits and possibilities for improvement. There are lessons from land-based gas turbines which can be applied to aircraft, notably the small increases in efficiency from further increase in pressure ratio and turbine inlet temperature. Land-based gas turbines also point to the benefit of combining the properties of water with those of air to raise efficiency. Whereas the incentive to raise efficiency and reduce CO2 will force an increase in complexity of land-based power plant, the opportunities for this with aircraft are more limited. One of the opportunities with aircraft propulsion is to consider the whole aircraft operation and specification. Currently the specification for new aircraft of take-off and climb thrust are not fully consistent with designing the engine for minimum fuel consumption and this will be addressed in some depth in the lecture. Preparing for the future entails alerting engineers to important possibilities and limitations associated with gas turbines which will mitigate climate change due to carbon dioxide emissions.