Electrification and renovation in the EU building sector decarbonization: a multi-model comparison

Policymakers rely on building sector energy models to design decarbonization strategies, yet different models can produce divergent projections even under similar assumptions. We address this through a systematic comparison of five building sector energy models (FORECAST-Buildings, Invert/EE-Lab, Invert/Opt, PRIMES-Buildings, EDGE/REMIND-Buildings) applied to shared scenario narratives for EU27. The scenarios vary along two dimensions: supply-side technology focus (electrification, district heating, hydrogen, and synthetic fuels) and demand reduction ambition (moderate efficiency, high efficiency, lifestyle change). High-efficiency scenarios achieve final energy demand reductions of 33% to 53% by 2050, while moderate-efficiency scenarios achieve 25% to 44%, depending on model structure and renovation dynamics. Electrification via heat pumps emerges as the dominant strategy across all scenarios, with projected capacity reaching 800 to 1600 GW by 2050 and electricity's share of final energy demand rising to 60% to 86%, even in scenarios not explicitly focused on electrification. In district heating-focused scenarios, shares reach 14% to 28% of final demand, while in other scenarios shares remain at 8% to 17%, reflecting sensitivity to spatial planning assumptions and infrastructure development. Hydrogen and synthetic fuels play only a marginal role, with shares below 10% by 2050. This comparison identifies heat pump electrification and deep renovation as robust, no-regret strategies, while clarifying conditions under which district heating becomes viable at scale. By comparing structurally diverse models under harmonized assumptions, this study provides policymakers with evidence on which strategies are robust regardless of the modeling approach.