Can coal keep gas turbines in utility generating plans

The future of the gas turbine in electric utility generating systems may depend on its ability to burn coal. Research programs to develop that ability that are being conducted by gas turbine manufacturers, the Electric Power Research Institute, and the Energy Research and Development Administration were the main points of discussion at the recent ASME gas turbine conference in Philadelphia. If coal-burning capability isn't developed, the gas turbine faces a very cloudy future with utilities. Existing gas turbine fuels--natural gas and distillate oil--may be impossible to get in the near future, particularly for new installations. Last winter's natural gas crisis makes it highly unlikely that a utility would be permitted to divert gas from the residential market to fuel a new gas turbine. The national effort to reduce oil imports puts No. 2 distillate, kerosene, and even resid into the doubtful category. Fortunately, gas turbines and coal form a promising symbiotic relationship for energy R and D planners. To some extent they depend on each other. Coal's future with electric utilities is being hamstrung by restrictive environmental regulations. If stack gas cleanup systems can't make coal acceptable, then utilities will have to turn to clean, coal-derived synthetic fuels. However, themore » energy loss in coal conversion systems is about 30 percent. It is attractive, conceptually, to consider using these coal synthetics in a combined cycle so that the energy loss in conversion is recovered via the enhanced efficiency of the combined gas turbine/steam cycle. Strong reservations do exist, though, regarding the reliability of present-day turbines burning oil, let alone coal. (MCW)« less