# Buildings and Energy — Heating, Cooling and the Net-Zero Building

**URL:** https://thecodex.expert/energy/buildings/
**Session:** 28 | **Date:** 2026-05-05

## Summary

Buildings consume ~40% of global final energy (IEA 2023), ~10 Gt CO₂/yr. Heat pumps: COP 2.5-5.0 vs gas boiler COP 0.85-0.95 — 3-5× more efficient. ~190 million units globally (IEA 2022). IEA NZE 2050 requires 1 billion heat pumps by 2030 (7× scale-up). Passive House standard (Germany): reduces heating demand 80-90%. India: ~60 million ACs installed, projected 1 billion by 2050 (IEA) — India adds more AC than any other country. UJALA scheme: 360 million LEDs, 9 TWh/yr savings. SEEP programme: 5-star AC standard by 2030. ECBC 2017 (BEE): commercial buildings >500m². EU EPC: mandatory energy certificates, F-G buildings to minimum E by 2030. UK retrofit: 19 million homes below EPC C, ~£300 billion cost. Retrofit barriers: upfront cost, disruption, split incentive (landlord-tenant), planning restrictions. Sources: IEA Buildings 2023, BEE India AR 2024, Passive House Institute.