Small demonstrator of a thermoelectric heat-pump booster for an ultra-low-temperature district-heating substationTomc, Urban (Avtor) Nosan, Simon (Avtor) Vidrih, Boris (Avtor) Bogić, Simon (Avtor) Navickaite, Kristina (Avtor) Vozel, Katja (Avtor) Bobič, Miha (Avtor) Kitanovski, Andrej (Avtor) district heatingthermoelectricsheat pump boosterenergy efficiencyheat pumpboosterHeating and cooling systems account for approximately 50% of global energy consumption and contribute 40% of carbon dioxide emissions. District-heating systems offer enhanced energy efficiency, diversification, independence from energy sources, and the utilization of waste and renewable energy sources. One key energy-efficiency measure in district heating is reducing the supply and return temperatures. Fourth-generation district-heating systems operate with supply temperatures of 50 to 60 °C, enabling better utilization of renewable and waste heat. Fifth-generation district-heating systems further lower the supply/return temperatures, requiring additional heat sources, such as boosters, to heat domestic hot water. Heat pumps, specifically vapour-compression heat pumps, are the most energy-efficient devices for converting fuels or electricity into heat for space and water heating. However, vapour-compression technology faces challenges related to environmentally friendly refrigerants, noise, vibration, compactness, and energy efficiency, especially for small units. In this study, we introduce a novel design of thermoelectric-based heat-pump booster. Despite its lower exergy efficiency, this technology offers advantages such as compactness, silent operation without vibration, easy power control, and longevity. We demonstrate that these thermoelectric heat-pump boosters can increase the supply-water temperature of district-heating systems from around 32 °C to 42 °C, with a heating coefficient of performance equal to 2.4 and an exergy efficiency of 9.9%.20242024-02-27 13:45:43Članek v reviji154739sl