Evaluation of the cost of using power plant reject heat in low-temperature district heating and cooling networks

The purpose of this paper is to assess the economic impact following as a result of the conversion of conventional stations to cogeneration plants connected to a system for distributing heat and refrigeration. The analysis will be carried out through a financial evaluation in order to assess yearly variations of the whole scheme expenditure. In particular, yearly capital and operating costs of supplying cold and heat to urban areas that represent weather conditions in northern, central, and southern Europe were studied. In the base case scenario, today conditions are represented; they will be compared with alternative scenarios in which existing conventional thermal power stations will be converted into cogeneration plants. This research work contributes to the pool of existing knowledge by giving a (so far not addressed) weather centered system perspective. From the conducted evaluation, it was found that, in the case of deciding to convert the studied conventional thermal plants into cogeneration plants, investing in the necessary infrastructure associated means that yearly expenses for the power plants located in Oldenburg-Wilhelmshaven, Bristol, and Cartagena would decrease by 215, 89, and 192 million euros respectively, making this technology a highly attractive option from economic, energetic, and environmental perspectives.