Energy Efficiency Subsidies Compared: FR vs DE vs IT vs BE vs ES

Developers building multi-country renovation tools often ask us: “Which country is the most generous?” The answer is always: “It depends on the work type, the household income, and whether you count tax deductions as grants.” This article gives you the definitive comparison, broken down by work type, with real numbers from the GreenCalc subsidy database.

All amounts below are for a reference project on a detached house with a moderate-income owner-occupier, unless otherwise noted. For a broader overview, see our EU Renovation Subsidies Guide 2026.

Heat pumps: the headline subsidies

Heat pump replacement is the most heavily subsidized renovation work in Europe. Every country prioritizes it because heat pumps directly replace fossil fuel heating. Here is what a moderate-income household receives for a typical €16,000 air-water heat pump installation:

*Germany’s 35% includes the 10% oil boiler replacement bonus. Without the bonus, it is 25%.

Winner for heat pumps: France for direct grants (75% for moderate income). Italy for total subsidy value (65% of any cost level, no income threshold, but it is a tax deduction over 4 years). For the full breakdown, see our dedicated heat pump subsidies article.

Roof insulation: per-m² vs. percentage

Insulation subsidies reveal a fundamental design difference between countries. France pays per square meter. Germany pays a percentage of cost. Italy deducts a percentage from taxes. This makes comparison tricky because the effective subsidy depends on your contractor’s price.

Reference project: 80m² roof insulation costing €8,000 (€100/m²):

Winner for roof insulation: Italy (65% Superbonus, if the project qualifies as a driving work). France comes second when you add CEE certificates on top of MaPrimeRenov. Germany is notably lower because insulation gets the base 15% rate with no bonuses.

Wall insulation (exterior): the expensive one

Exterior wall insulation (ITE in France, WDVS in Germany, cappotto termico in Italy) is the most expensive common renovation work, often costing €150–200/m². Subsidies matter a lot here.

Reference project: 100m² exterior wall insulation costing €18,000:

Winner for wall insulation: Italy again, but wall insulation (≥25% of the building envelope) is also the main “driving work” that unlocks Superbonus for other measures. So it serves double duty in Italy.

Windows: the underdog upgrade

Window replacement is moderately subsidized across Europe. It is rarely the primary renovation work but is frequently added to larger projects. Reference: 8 windows costing €6,400 total:

Winner for windows: Italy under Superbonus (but windows alone do not qualify — they must be paired with a driving work like wall insulation). As a standalone measure, Spain offers the best percentage-based grant.

Solar panels (photovoltaic): the special case

Solar PV subsidies vary the most across countries because some have shifted from installation grants to feed-in tariffs or net metering. Reference: 6kWp PV system costing €9,000:

Winner for solar PV: Italy (Superbonus) for upfront value. Spain offers the best combination of installation grant + local tax benefits. France and Germany have shifted to feed-in mechanisms instead of installation grants.

The overall scoreboard

The pattern is clear: France wins for low-income households (income-tiered grants are very generous at the bottom), Italy wins for total subsidy value (65% of everything, but as tax deductions), and Germany is the simplest (flat rates, no income test, but lower percentages).

Running the comparison via API

To compare subsidies across countries programmatically, send the same project with different country_code values:

# Compare heat pump subsidy across all 5 countries
for country in FR DE IT BE ES; do
  echo "=== $country ==="
  curl -s -X POST https://greencalc.io/api/v1/eligibility/simulate \
    -H "X-Api-Key: gc_sandbox_000000000000000000000000000000000" \
    -H "Content-Type: application/json" \
    -d "{
      \"country_code\": \"$country\",
      \"household\": {
        \"annual_income\": 35000,
        \"household_size\": 3,
        \"is_owner\": true
      },
      \"property\": {
        \"type\": \"HOUSE\",
        \"energy_rating\": \"E\",
        \"postal_code\": \"00000\",
        \"surface_m2\": 100
      },
      \"planned_works\": [
        {\"work_type\": \"HEAT_PUMP_AIR_WATER\", \"estimated_cost_eur\": 16000}
      ]
    }" | jq '.summary'
done

For building a visual comparison tool, see our renovation cost calculator tutorial. For country-specific deep dives, see the MaPrimeRenov guide, KfW guide, and Superbonus guide.

GreenCalc is built by AZMORIS Group. Data sourced from official government publications. Amounts shown are for the 2026 subsidy year.