The Boiler Upgrade Scheme (BUS) provides upfront grants to support installation of air and ground source heat pumps. It launched in April 2022 and is expected to run for 3 years, until March 2025. Grants of £5,000 are provided for air source heat pumps and £6,000 for ground source heat pumps.
This is the first of two posts breaking down the comprehensive guidance for property owners published by Ofgem, who administer the BUS. The second post will describe the application process from the homeowner's point of view.
All the information below is laid out in the guidance document which is about 40 pages long (with a full 7 pages for the eligibility criteria). Therefore I felt compiling a shorter version would be useful. I believe the criteria below are comprehensive, but do get in touch if you think anything has been left out.
I've divided the eligibility requirements into three sections: requirements on the property, on the installer, and on the installation.
Part 1: Requirements for the property
Location: Properties must be within England or Wales.
Type: Properties can be domestic or non-domestic. Domestic properties may be owner-occupier, rented to tenants, second homes, and holiday homes.
Current system: Properties must be currently heated with either fossil fuel heating system or an electric system that does not include a heat pump. Properties with storage heaters, electric panel radiators, and electric boilers are all eligible.
New builds: New build properties are eligible if they are owned and built by individuals, either through a builder or a DIY project. Commercial property developers cannot apply for the BUS, and social housing is also not eligible.
Energy performance certificate (EPC): The property must have an EPC, unless it is a self-build.
Energy efficiency: The EPC must have no recommendations for loft or cavity wall insulation, OR evidence must be provided that the property is exempt from these requirements. Potential reasons for exemption from the insulation requirement are listed below.
Recommendations for solid wall insulation, floor insulation, and other measures do not affect eligibility. This includes room-in-roof insulation.
If the property's EPC does recommend cavity or loft insulation, it is possible to go ahead with the BUS application and heat pump installation, provided that the insulation is installed and a new EPC is obtained before the BUS voucher is redeemed.
Possible reasons for exemption from loft and cavity insulation requirements
Property is a listed building
Property is in a conservation area
Property houses a protected species that would be materially affected by the installation of the insulation (most likely – though not necessarily – bats)
Due to local environmental conditions (for example regular exposure to driving rain).
Due to the structure of the building (for example it’s a timber framed building).
Because it would be otherwise unlawful.
The Ofgem guidance also lists the documents that must be provided with the BUS application to prove that the property is exempt from the insulation requirement.
Part 2: Requirements for the installer
The installer must be MCS accredited and certified to install heat pumps.
The installer must be registered for a BUS account prior to making any applications for the scheme.
Part 3: Requirements for the installation
System type: Air, ground, and water source heat pumps are eligible. Ground source heat pumps making use of a shared ground loop are also eligible. Biomass boilers are also eligible, but only for existing (i.e. not self-build) rural properties without a gas grid connection.
System efficiency: Heat pumps must have a seasonal coefficient of performance (SCOP) of at least 2.8.
Heat distribution system: The new system must be hydronic, i.e. it must make use of a wet radiator heat distribution system. Air-to-air heat pumps are not eligible.
Full replacement: The new system must completely replace the previous fossil fuel or electric heating system. Heat pump systems which use a combination of a fossil fuel boiler and a heat pump are not eligible.
Retaining components: A number of components can be retained from the existing components. These are listed below.
Date of commissioning: The system must be commissioned after 1 April 2022.
For self-builds, the system must be commissioned before the building is first occupied.
Size: The total capacity of the installed heating system must be less than 45 kWth.
Typical domestic installations are between 5 and 15 kWth so this limit is not likely to impact the vast majority of domestic properties.
For ground source heat pumps using a shared ground loop, the combined capacity of all heat pumps on the shared loop must be less than 45 kWth.
Heat and hot water: The new system must provide both space and hot water heating, and be capable of meeting the full space heating and hot water heating demands of the property.
Funding: The installation cannot receive public funding from other sources in addition to the BUS.
Components that can be retained from the previous system:
Hot water cylinders and immersion heaters for hot water
Buffer tanks, thermal stores, and expansion vessels
Circulation pumps, pipes, and emitters (e.g radiators)
Supplementary electric heaters, wood burning stoves, and night storage heaters
Solar thermal collectors
Containers and fixings
Control system
Note that this list is contained in Ofgem's installer guidance rather than the property owner guidance.