Page type: primary-anchored (mirrors Boiler Upgrade Scheme (England and Wales) Regulations 2022, SI 2022/565)
Boiler Upgrade Scheme (BUS) Regulations
The Boiler Upgrade Scheme (England and Wales) Regulations 2022 create a voucher-based capital grant for replacing fossil fuel or electric heating with heat pumps or biomass boilers. Ofgem administers the scheme. It replaced the RHI for new domestic installations, using a one-off grant rather than 20 years of tariff payments.
Primary source: ~/knowledge/sources/legislation/uk/si-2022-565-bus.md
Last updated: 2026-04-05
Grant amounts (current 2025)
| Technology | Grant |
|---|---|
| Air source heat pump | GBP 7,500 |
| Ground source heat pump | GBP 7,500 |
| Biomass boiler | GBP 5,000 |
| Air-to-air heat pump | GBP 2,500 |
| Heat battery | GBP 2,500 |
Amounts are published by the Secretary of State under Reg 13, not hardcoded in the SI. They can be adjusted without amending the Regulations.
How it works
- Property owner engages an MCS-certified installer
- Installer applies to Ofgem for a voucher (processed first-come-first-served)
- Ofgem issues a voucher: 3-month validity for ASHP/biomass, 6 months for GSHP
- Installation completed within the voucher period
- Installer submits a redemption application to Ofgem
- Ofgem pays the grant to the installer, who passes the benefit to the owner as a price reduction
Property eligibility (Reg 5)
Must be a building (not social housing) with a valid EPC (within 10 years) and existing fossil fuel or electric heating. Previous BUS grants for the same technology at the same property disqualify.
Social housing is excluded; its decarbonisation is handled through SHDF and ECO4.
Technology standards
Heat pumps (Reg 9): maximum 45 kWth (300 kW for shared ground loops), seasonal CoP of at least 2.8, electric compressor, liquid-based heating delivery.
Biomass boilers (Reg 10): maximum 45 kWth, approved emission standards, liquid-based heating. Restricted to rural, off-gas, non-new-build properties (Reg 11) due to air quality concerns.
Design comparison with RHI
| Feature | RHI | BUS |
|---|---|---|
| Payment | Per-kWh tariff over 20 years | One-off capital grant |
| Fiscal exposure | Long tail (to ~2043) | Bounded by annual budget |
| Recipient | Installation owner | MCS installer |
| Scope | England, Wales, Scotland | England and Wales only |
Cross-references
- RHI Regulations, the predecessor tariff scheme
- ECO4 Order, supplier obligation covering social housing
- BUS wiki page, operational scheme page
- Energy Act 2008, ss.100, 104(2): enabling power