20.500.12556/RUL-154739 Small demonstrator of a thermoelectric heat-pump booster for an ultra-low-temperature district-heating substation Heating 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%. district heating thermoelectrics heat pump booster energy efficiency heat pump booster daljinsko ogrevanje termoelektrika podporna toplotna črpalka energijska učinkovitost true false true Angleški jezik Slovenski jezik Članek v reviji 2024-02-27 13:45:43 2024-02-27 13:45:50 2024-05-24 03:56:49 0000-00-00 00:00:00 2024 0 0 14 str. Vol. 361, art. 122899 May 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 697 1872-9118 10.1016/j.apenergy.2024.122899 186961923 1-s2.0-S0306261924002824-main.pdf 1-s2.0-S0306261924002824-main.pdf 1 B1A0989D5584FD7A41339C8B806101FD 6a43a54906432156f7764924825e382942e1e5a98ef28f590de31f2f38d5e3e4 e255a1fb-1901-11ef-850a-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=183843 https://www.sciencedirect.com/science/article/pii/S0306261924002824 1 237a6ee9-d56e-11ee-9672-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=181290 Fakulteta za strojništvo 0 0 0