The latest data available for the Domestic Renewable Heat Incentive covers the period from the launch of the scheme on April 9th, 2014 to the end of March, 2021.
The Domestic Renewable Heat Incentive (Domestic RHI) is a UK Government scheme to encourage the use of renewable heating technologies. Under the scheme householders receive quarterly payments for a period of 7 years, based on the amount of renewable heat their system produces.
As the main funding vehicle for renewable heating technologies, the domestic RHI gives us a good indication of installation numbers and the state of the market for renewable heating technologies. In the Domestic Renewable Heat Update we look at the quarterly status of heat pumps, biomass and solar thermal installations in the UK.
Air source heat pumps account for 68% of new installations since the start of the domestic RHI. Biomass, was the most popular technology over the first year of the scheme but accounts for just 15% of new installations overall. In recent quarters, ground source heat pumps has consistently been the second strongest technology, albeit a distant second when compared with air source installation numbers.
Key Points From March 2021
A Strong Quarter and a Strong Year for Renewable Heat Installations
The first quarter of 2021 was a strong one for the domestic RHI, with 3,876 new applications. That’s more installations than in any quarter since early 2015. This follows on from a 4th quarter in 2020 that also set records with 3,761 installation. The year from April 2020 to March 2021 saw 12,221 new domestic RHI applications, despite a significant impact from COVID-19 in the first few months of the pandemic.
Air source heat pumps dominate these new installations, with figures for the other technologies a bit more of a mixed bag.
Air Source Heat Pumps See Record Growth, Again
Quarterly air source heat pump installations grew to 3,224 in the 1st quarter of 2021. The past year has seen record numbers for domestic air source installations, despite the impact of COVID which was significant in the first 2 quarters. Air source heat pumps have come to dominate installation numbers over the course of the domestic RHI.
Ground Source Installations are Rising
Ground source heat pump numbers have never competed with the huge peaks biomass achieved early in the scheme, or the increased adoption rate of air source heat pumps. Adoption of ground source since the launch of the domestic RHI might best be described as slow and steady. Ground source heat pumps have seen growth over the last 2 quarters with Q1 of 2021 being the strongest since the start of the domestic RHI. Overall, the experience since the start of the scheme seems to be one of stability. Ground source heat pumps have consistently been the second largest technology under the domestic RHI for several years now. 425 installs on the quarter is a record for ground source but that number is dwarfed by air source which had 3,224 new installations in the same period.
Biomass Yet to Recover
Between the launch of the Domestic RHI in early 2014 and the end of 2015 the tariff rates paid for biomass had roughly halved. Just glancing at the installation figures and the overwhelming popularity of biomass in the early days of the scheme might support the notion that biomass was over funded. It is equally clear from the figures that biomass installations have never recovered from the cuts. From the start of 2016 until now, biomass installation numbers under the domestic RHI have been behind ground source heat pumps in every single quarter.
Solar Thermal Installation Numbers Remain Low
Solar thermal has never been popular under the domestic RHI and the latest quarter shows just 79 new applications. That is roughly in line with quarterly numbers for solar thermal over the last 8 quarters or so.
New Applications by Installed Technology
New applications are for systems installed since the launch of the scheme on 9th April 2014.
| Technology | Applications | Accreditations | ||
|---|---|---|---|---|
| Number | % | Number | % | |
| Air Source Heat Pump | 43,502 | 68% | 42,673 | 67% |
| Ground Source Heat Pump | 7,117 | 11% | 7,020 | 11% |
| Biomass | 9,458 | 15% | 9,367 | 15% |
| Solar Thermal | 4,265 | 7% | 4,240 | 7% |
| Total | 64,402 | 100% | 63,300 | 100% |
Total Applications by Installed Technology
Total applications include both new applications and legacy applications.
| Technology | Applications | Accreditations | ||
|---|---|---|---|---|
| Number | % | Number | % | |
| Air Source Heat Pump | 55,057 | 62% | 54,217 | 62% |
| Ground Source Heat Pump | 12,004 | 14% | 11,837 | 14% |
| Biomass | 12,435 | 14% | 12,339 | 14% |
| Solar Thermal | 8,972 | 10% | 8,944 | 10% |
| Total | 88,468 | 100% | 87,337 | 100% |
