Short read. This is a ~300-word brief based on the full analysis at Househeating Pulse. For the interactive charts, brand-level data, and source tables, open the original.
The payback split in 2026 is less about the heat pump itself than the emitter system behind it. When the same unit is paired with underfloor heating instead of high-temperature radiators, it can hold closer to SCOP 4 territory, and that difference is enough to move several markets from “borderline” to “credible retrofit.”
The country-level trigger is the electricity-to-gas price ratio from Eurostat household bands DC/D2. Househeating Pulse’s latest table puts Sweden at 1.3, France at 1.78, Germany at 3.16, Poland at 3.71, and Romania at 5.11. That matters because SCOP 4 is roughly the break-even zone when electricity costs about 3.7 times gas; below that, heat pumps have room to work, while above it, radiator-driven systems get expensive fast. Poland is the most obvious edge case: it sits just over the line at 3.71, so any efficiency loss from a hotter emitter circuit hits payback immediately.
The EPREL Public API aggregation in the article shows why emitter choice is only one layer. Air-water units average SCOP 4.54 across 30,452 models, while ground-water units average 4.77 across 213 models. That 0.23-point gap is modest in absolute terms, but it still shifts running cost by about 5.1% relative to air-water. For developers building models off live product registries, the important point is that type-level efficiency and system-level delivery are both needed to reproduce payback correctly.
The strongest underfloor-heating cases combine low tariff ratios with heating demand. Sweden pairs 1.3 with 4,242 HDD18, France combines 1.78 with 2,759.65 HDD18, and the Netherlands sits at 1.49 with 2,901.04 HDD18. By contrast, Belgium, the UK, Romania, and Poland sit at 3.9, 4.63, 5.11, and 3.71 respectively — a much harsher environment for radiator retrofits.
Read the full analysis with live data on the canonical page: https://househeating-pulse.com/guides/2026-heat-pump-radiator-vs-underfloor-payback-by-country
For the full country-by-country breakdown, read the full analysis with live data here: https://househeating-pulse.com/guides/2026-heat-pump-radiator-vs-underfloor-payback-by-country
Househeating Pulse aggregates 60,000+ EPREL-registered heat-pump models across Europe — efficiency rankings, refrigerant trends, country-level installed prices and subsidies. Data from EPREL, Eurostat, NASA POWER. Full analysis at https://househeating-pulse.com/guides/2026-heat-pump-radiator-vs-underfloor-payback-by-country.
