Demonstration of a 43 % electric efficient 1,4 MWe gas turbine for the supply of heat in a district heating system in Nancy (FR) and the supply of electricity to the national grid in the contract period November - March and moreover to ameliorate the present negative environmental effect of energy from coal and fuel oil. Heat production is variable between 1,0 - 2,5 MWth. The innovations are an electric efficiency of 43%, compared to the 20 - 25% for gas turbines of comparable size and compared to the 38,5% of the THERMIE-supported proof of concept test model. NOx emission level is < 10 ppmv. Two-stage combustion, intercooling, heat recuperation, low temperatures and pressures, all so typical for the cycle, allow for the high electric efficiency, a high lifetime and low maintenance costs. The project saves 560 TOE/ a. The payback time is 10 years in project's 5 month operation and 6 - 7 years in future commercial applications.