Where DUOHEAT is aiming
A temperature lift of at least 100 K, heat delivered at up to 200 °C, and a coefficient of performance (COP) of 2.5–8 — a step beyond published high-temperature heat pump designs.
A commercially viable high-temperature heat pump
DUOHEAT's goal is to design, build and prepare for commercialisation a two-stage high-temperature heat pump capable of producing heat at up to 200 °C, with a temperature lift — the gap between the source and delivery temperature — of at least 100 K. Reaching that lift efficiently is what the rest of this page compares against published alternatives.
Reaching higher temperatures at a higher COP
Published high-temperature heat pump designs typically trade off delivery temperature against efficiency: the hotter the output, the lower the COP tends to fall. DUOHEAT's two-stage compressor and mixing-type heat exchanger are designed to hold a higher COP while reaching a higher delivery temperature than the designs reported in the literature below.
Delivered temperature (°C)
Coefficient of performance (COP)
| Source | Evaporation temp. [°C] | Condensing temp. [°C] | Compressor efficiency | Heating power [kW] | COP |
|---|---|---|---|---|---|
| Bobelin (2012) | – / 36–60 | – / 80–138 | 70% | 50–200 | 1–5 |
| Mateu-Royo (2019) | 60–80 / – | 90–140 / – | 60.3% | 10.9–17.5 | 2.2–3.4 |
| Xu (2021) | 45–65 / – | 80–100 / – | 75% | 12 | 4–5.7 |
| DUOHEAT | 50–90 / 30–70 | 110–200 / 115–210 | 80% / 78% (high-/low-pressure stage, isentropic) | 50–1000 | 2.5–8 |
The charts above are DUOHEAT's own visualisation of the figures in this table — not a reproduction of any published chart.
- Bobelin, D., & Bourig, A. (2012). “Experimental Results of a Newly Developed Very High Temperature Industrial Heat Pump (140 °C) Equipped With Scroll Compressors and Working With a New Blend Refrigerant.” Paper 2435. International Refrigeration and Air Conditioning Conference at Purdue. docs.lib.purdue.edu/iracc/1299
- Mateu-Royo, C., Navarro-Esbrí, J., Mota-Babiloni, A., Molés, F., & Amat-Albuixech, M. (2019). “Experimental exergy and energy analysis of a novel high-temperature heat pump with scroll compressor for waste heat recovery.” Applied Energy, 253, 113504. doi.org/10.1016/j.apenergy.2019.113504
- Xu, C., Yang, H., Yu, X., Ma, H., Chen, M., & Yang, M. (2021). “Performance analysis for binary mixtures based on R245fa using in high temperature heat pumps.” Energy Conversion and Management: X, 12, 100123. doi.org/10.1016/j.ecmx.2021.100123
Related international context: IEA Annex 58, Task 1.
Target sectors
DUOHEAT is aimed at heating and combined heat-and-power plants, together with industrial sectors that rely on high-temperature processes.
Heating & CHP plants
Drying & pasteurisation
Chemical processing
Food production
Beyond the technology itself
DUOHEAT supports a more sustainable heat economy: replacing fuel-fired heating with electrified, waste-heat-driven heat reduces emissions and improves the energy efficiency of industrial processes. A stable link between electricity demand for heat production and the power grid also supports the growth of renewable energy and the efficient use of the nuclear capacity planned for Poland's power system. Pairing high-temperature heat pumps with energy storage is a further way to avoid non-market curtailment of electricity. The most difficult benefit to measure, but perhaps the most important, is the social one: decarbonising heating and industry and reducing CO₂ emissions.