The paper is devoted to some problems connected with last modification of EU directive on energy efficiency, viz.: free choice of the measure concerning the improvement of energy efficiency, i.e. final or primary energy consumption, corresponding energy savings or energy-consumption index; however without cumulative consumption or cumulative savings of primary energy. In EU directive it has been stressed the importance of measurements systems (reliable measurement information); but has not been recommended any advanced validation of measurements results, nor energy auditing or algorithms of calculating the energy savings due to improvement of energy efficiency concerning large industrial plants. Evaluation of complex buildings should be realized by means of the system method (input-output analysis). The separate problem is devoted to application of thermo-ecological approach in the analysis of complete results of improving the energy efficiency. Human activity is connected with the depletion of nonrenewable resources, including primary energy, due to not only production of consumer goods but also the necessity of compensating the unfavourable effects of harmful emissions from energy-technological processes. Therefore the index of energy-ecological efficiency has been proposed as the most competent evaluation of improvement energy efficiency of production processes and systems.
Szargut proposed the algorithm for determination of the influence of irreversibility of components of thermal process on the emission of CO2 [6]. In the presented paper, basing on Szargut's proposal, the example of analysis of influence of operational parameters of coal fired power plant on the local increase of CO2 emission is presented. The influence of operational parameters on the local exergy losses appearing in components of investigated power plant are simulating making use of the semi-empirical model of power plant.
The paper is devoted to the problems of exergetic cost determination. A brief description of theoretical fundamentals of exergetic cost determination and its application are presented. The applied method of calculations is based on the rules of determination of cumulative exergy consumption. The additional possibilities ensured by the exergetic cost analysis in comparison to the direct exergy consumption analysis are discussed. The presented methodology was applied for the analysis of influence of operational parameters on exergetic cost indices of steam power plant. Results of calculations concern one of the modern Polish power plant unit. Basing on the obtained results several conclusions have been formulated that show advantages of application of exergetic cost analyses.