Small demonstrator of a thermoelectric heat-pump booster for an ultra-low-temperature district-heating substation

Tomc, Urban (author), Nosan, Simon (author), Vidrih, Boris (author), Bogić, Simon (author), Navickaite, Kristina (author), Vozel, Katja (author), Bobič, Miha (author), Kitanovski, Andrej (author)

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%.

• Language: English
• Keywords: district heating, thermoelectrics, heat pump booster, energy efficiency
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 14 str.
• Numbering: Vol. 361, art. 122899
• PID: 20.500.12556/RUL-154739
• UDC: 697
• ISSN on article: 1872-9118
• DOI: 10.1016/j.apenergy.2024.122899
• COBISS.SI-ID: 186961923
• Publication date in RUL: 27.02.2024

Record is a part of a journal

• Title: Applied energy
• Publisher: Elsevier
• ISSN: 1872-9118
• COBISS.SI-ID: 23073029

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: daljinsko ogrevanje, termoelektrika, podporna toplotna črpalka, energijska učinkovitost