Europe 2026: R290 vs R32 shows the biggest efficiency gap in air-to-water heat pumps

The type split: where refrigerant changes efficiency most

R290’s efficiency edge is measurable in 2026, but the clearest gap appears in air-to-water units: average SCOP is 4.54 for the full air-to-water pool, and the underlying R290-vs-R32 comparison supplied for this article points to air-to-water as the type with the largest refrigerant split, while other categories are too small or too close to support the same headline (type_efficiency).

That nuance matters because Europe’s heat-pump market is not one market. EPREL now contains 60,989 listed models across five product types, but only three of those types carry SCOP data in the corpus: 30,452 air-to-water units, 213 ground-water units, and 31 water-water units, versus 21,065 air-air models and 9,228 heat-pump water heaters without comparable SCOP values in this dataset (market_index_snapshot) (type_efficiency).

So the first ranking point is straightforward: air-to-water is where refrigerant choice matters most in commercial terms because it is both the largest comparable category by far, at 30,452 models, and the one identified in the brief as having the biggest average SCOP gap between R290 and R32 (type_efficiency). By comparison, water-water is statistically tiny at 31 models, and ground-water, while larger than that, still has only 213 models in the corpus (type_efficiency).

The corpus does not include the by-type split of average SCOP for R290 versus R32, so the exact average SCOP for air-to-water R290 and air-to-water R32 — and the exact absolute gap in SCOP points — cannot be stated from the supplied data alone. The same limitation applies to identifying the smallest gap category with a numeric difference, even though the article angle provided says the non-air-to-water categories are much closer.

Readers who want to inspect the relevant product universe can compare the air-to-water catalog, the R290 listings, and the broader market index snapshot.

Air-to-water as the main battleground for R290 vs R32

Air-to-water is where the market is concentrated, with 30,452 models, or just under half of all 60,989 listed heat pumps in the snapshot (market_index_snapshot) (type_efficiency). Its average SCOP is 4.54, slightly below the overall market average of 4.55, and its average declared capacity is 11.83 kW with average outdoor noise of 59.8 dB (market_index_snapshot) (type_efficiency).

That matters for the refrigerant comparison because a gap inside air-to-water is a gap in the category that buyers and installers most often cross-shop. Ground-water units post a higher average SCOP of 4.77, but they are a much smaller niche at 213 models and have much larger average capacity at 18.45 kW (type_efficiency). Water-water is higher still at 6.15 SCOP, but it is effectively a specialist category with only 31 models and a very different size profile at 35.65 kW on average (type_efficiency).

On acoustics, air-to-water units sit near the middle of the comparable set at 59.8 dB average outdoor noise, against 58.8 dB for ground-water and 42.0 dB for water-water (type_efficiency). That does not show that the R290 advantage is simply a function of larger or noisier equipment; if anything, the type-level averages show that the highest-SCOP type in the dataset, water-water, is also the quietest and the largest, while the mainstream air-to-water segment combines moderate size, moderate noise, and the key refrigerant contest (type_efficiency).

For performance shoppers, the useful reference points are the air-to-water top-SCOP leaderboard, the full heat-pump catalog, and the methodology page explaining how SCOP and other fields are handled.

Where the gap narrows: smaller or flatter type categories

Outside air-to-water, the story gets thinner fast. Ground-water has enough models to be visible, but only 213 of them, versus 30,452 air-to-water units — roughly 143 air-to-water listings for every one ground-water listing in the corpus (type_efficiency). Water-water has just 31 models, making any refrigerant split there inherently fragile as a market signal (type_efficiency).

That is why the corpus supports a narrower claim than many marketing narratives make. Yes, refrigerant matters. But the market-wide effect is type-dependent, and the categories beyond air-to-water are either too small, too specialized, or too structurally different in size and application to read as a clean like-for-like referendum on R290 versus R32 from this dataset alone (type_efficiency).

The same caution applies to air-air and heat-pump water heaters. They are large categories — 21,065 and 9,228 models respectively — but the supplied corpus does not provide SCOP values for them, so they cannot be used in the refrigerant efficiency ranking here (type_efficiency). That absence is important: any claim that R290 or R32 wins across “all heat pumps” would overstate what the supplied data can actually show.

For broader context on refrigerant families and regulation, the refrigerants reference shows R290 as a natural refrigerant with GWP 0 and R32 as an HFC with GWP 771 and a 2027-01-01 phase-out date in the supplied table (refrigerant_universe).

How much of each refrigerant is actually in the market

The declared-usage imbalance between the two refrigerants is stark. EPREL listings in the corpus show 13,935 models using R32, versus 537 using R290 (market_index_snapshot) (refrigerant_universe). That means R32 appears about 26 times as often as R290 in declared listings, while natural refrigerants as a whole still account for only 3.27% of the market snapshot (market_index_snapshot).

That scale difference is one reason the efficiency discussion should be read carefully. A refrigerant can have an average edge and still represent a small installed-choice set in current listings. Buyers comparing options today are therefore looking at a deep R32 product pool in market terms, and a much thinner R290 product pool (market_index_snapshot).

The corpus does not include the requested split showing what share of R290 listings and what share of R32 listings sit in air-to-water versus other types. So that specific market-allocation question cannot be answered numerically from the supplied data.

What the top-model tables show about the best-performing designs

The supplied top-model probes for air-to-water R290 and air-to-water R32 return empty arrays, so there is no model-level leaderboard evidence in this corpus to compare the best-performing named designs head to head (top_models). That means this article cannot say whether the top of the market is dominated by one refrigerant or whether the peak SCOP ceiling differs materially between them.

What can be said is that the market leaders by model count are still large diversified manufacturers rather than niche propane-only specialists. Daikin Europe N.V. has 14,668 listed models and a 24.05% market share, followed by Mitsubishi Electric Europe B.V. with 5,575 models and 9.14%, and Bosch Thermotechnik GmbH with 3,602 models and 5.91% (market_index_snapshot). Their average SCOP values in the snapshot are 4.44, 4.51, and 4.69 respectively (market_index_snapshot).

So the top-table takeaway is mostly methodological: use the leaderboards hub and top SCOP air-to-water page for product discovery, but do not infer a refrigerant-wide winner from empty or incomplete model-level extracts.

What buyers and installers should infer from the efficiency spread

The practical read is not “R290 wins everywhere.” It is “the strongest efficiency case for R290 is in air-to-water, the biggest category, while the rest of the market looks less decisive from the supplied evidence.” Air-to-water alone accounts for 30,452 models, far more than ground-water’s 213 and water-water’s 31, so that is where a real average SCOP advantage would matter most for annual running cost (type_efficiency).

But buyers should also note what the corpus does not prove. It does not quantify the exact R290-versus-R32 SCOP gap by type, it does not show the refrigerant-by-type listing shares, and it does not provide model-level top-performer tables for the two air-to-water refrigerants in this snapshot (top_models). So the fairest inference is directional, not absolute.

For purchasers, that means screening first by application and type, then by individual model performance, noise, and sizing rather than by refrigerant badge alone. The sizing calculator, payback calculator, and climate-fit analyzer are better next steps than assuming one refrigerant automatically means a better installation.

Sources

type_efficiency — EPREL Public API · type aggregation. Snapshot: 2026-06-05.
market_index_snapshot — Househeating Pulse · Market Index v1, computed from EPREL Public API. Snapshot: 2026-06-05.
refrigerant_universe — IPCC AR6 GWP table; EU Reg. 2024/573 phase-out schedule; EPREL declared codes. Snapshot: 2026-06-05.
top_models — EPREL Public API via Househeating Pulse catalog. Snapshot: 2026-06-05.