Energetic and economic assessment of cogeneration plants: a comparative design and experimental condition study

In the present paper, the nominal design data and the experimental data of eleven industrial cogeneration power plants, based on different prime mover technologies and actually in operation in Italy, have been compared. The aim of the study is to compare the expected energetic and economic results with the real performance and economic profitability of the plants in operation: the analyses have highlighted that, in the design phase, the simple payback time is usually underestimated. An assessment of the European incentives policy on cogeneration has also been undertaken, focusing on Italian legislation, which foresees a tax reduction for fuel and Tradable White Certificate support mechanisms: these incentives allow an average SPB reduction of about 15-20%. A sensitivity analysis on the SPB has also been performed, changing the fuel and maintenance costs, and the thermal and electrical energy prices, and the particular features of the different CHP technologies have been pointed out.