No abstract

Air-cooled condensers in thermal power plants have recently become increasingly popular. Besides all the advantages they have, like no demands for water supply on the plant site and no need for taking care of environmental regulations, they also have some serious disadvantages. One of the biggest disadvantages air-cooled condensers do have is precisely the nature of the Earth?s atmosphere being their low temperature reservoir. Low density and low heat capacity of the air as the cooling medium combined with extremely stochastic behavior of the atmosphere itself put some serious challenges in front of the air-cooled condenser?s proper and steady functioning. In this paper, the operating parameters of the air-cooled condenser in the chosen thermal power plant were investigated to gain a clearer insight into the influence of the atmospheric changes on its entropy generation and consequently on its efficiency. Also, the acquired results were further proposed as a starting point for potential optimization of the process inside the device.

No abstract

Modern society and economic development are completely dependent on various forms of energy while the ever-increasing demand for energy, in combination with significant environmental topics, has resulted in state-of-the-art ideas and solutions for fulfilling these often-contradictory goals, i.e. increasing efficiency or environmental protection and economic goal. The efficiency of the existing operating units for electricity production based on the usage of low-quality coal does not go hand in hand with the requirements of this new concept.One of the most efficient ways to reduce specific energy consumption is using Combined Heat and Power plants. In comparison to classical, separate heat and power plants, the advantage for CHP plants comes from their high efficiency. The result of higher efficiency is lower primary energy consumption and lower environmental pollution due to low values of CO2 emissions.Several revitalization configurations can be applied in order to fit the existing thermal power plants into combined cycles. The idea is to install, at the existing location, one gas turbine to increase the overall efficiency. This paper analyzes the potential of a combined gas-steam facility in the situation where the gas facility is used for heating feed water, which enters the heat recovery steam generator.A comparison of energy efficiency for various operating regimes, with and without heat production, is performed for this option.