Having the current constraints of serious water shortage which might cause more concern rather the depleting fuel resources and also the worrying global warming phenomenon, the power plants performance has to be evaluated based on not only energy efficiency but also water efficiency and environmental emission point of view. Therefore, power plants water consumption and emission production should be optimized simultaneous with the optimization of energetic performance. In other words, a high performance power plant would be considered as a high efficient, low water consumer and low emitting plant. In this paper the main indicators for the evaluation of energetic performance, water consumption and emission level of different pollutants are studied and then the global trend of these indicators for IRAN power plants investigated over a ten-year period, ending to 2012. The results show that the energetic performance of gas power plants seems to be higher than that of for steam and combined cycle power plants. Obtaining a 28 percent growth in overall energy efficiency of gas plants compared to the first year and achieving an average 85 percent peak load provision during ten years proved this fact. The water consumption criterion for wet-cooling steam plants decreased significantly to 0.6 m3/MWh at the end of tenth year. Finally, using the low quality fuel, whether oil or gas, has led to an 8.5 g/kWh SOx emission level from steam power plants. The most increase in CO2 emission is related to the steam power plants which has been equal to overall CO2 emission from the gas power plants, 850 g/kWh, at the end of ten-year period. © 2006-2016 Asian Research Publishing Network (ARPN).