Renewable Heat Incentive Statistics: Data From the Closed Scheme

The Renewable Heat Incentive (RHI) was the government's flagship scheme for paying households and businesses to switch from fossil fuel heating to renewable systems. First announced on 15 July 2009¹, it was set up in 2011 to boost rates of renewable and low-carbon heating in Great Britain². The domestic strand opened in April 2014 and paid households quarterly for seven years for the low-carbon heat their systems were expected to produce³. It closed to new applicants at midnight on 31 March 2022, but the payments continue for those already accredited, and the statistics the scheme generated are still the baseline against which UK renewable heat deployment is judged.

The headline numbers are straightforward. By the most recent count, 117,203 installations were accredited on the domestic scheme, and together they have generated around 10,745 GWh of heat since the scheme began⁴. Payments over the scheme's lifetime totalled £1,163,514,406, of which air source heat pumps took the largest share at 38.0 per cent⁵. An earlier official figure put the lifetime total at £1.06 billion as of 31 March 2024⁶, and government guidance has since referred to £1.2bn of payments since 2014⁷; the figures differ because they were drawn at different points as payments continued to accrue.

This page walks through what the scheme was, what the official statistics recorded, how the payments worked, why the scheme fell short of its ambitions, and what the closed scheme's data still tells a household thinking about renewable heating today.

A government scheme to pay for renewable heat

The plan to introduce the Renewable Heat Incentive was first announced on 15 July 2009¹, and the scheme was formally established as "a new Government scheme to promote the uptake of renewable heat"¹¹. The Renewable Heat Incentive was set up in 2011 to boost rates of renewable and low-carbon heating in Great Britain². The domestic strand, the Domestic Renewable Heat Incentive (DRHI), was introduced in 2014 as a government financial incentive to promote the use of renewable heat, which can help reduce carbon emissions and meet the UK's renewable energy targets³.

The reasoning behind paying for heat, rather than only for electricity, was that heat was the hard problem. Renewable electricity had its own support schemes, but the overwhelming majority of Britain's homes heated with gas, oil or electric resistance heaters, and the upfront cost of a heat pump, biomass boiler or solar thermal system was a barrier the tariff was designed to offset over time. The scheme's legal basis was the Domestic Renewable Heat Incentive Scheme Regulations 2014, as amended¹².

For a household, the scheme's promise was a stream of income that reduced the effective cost of installing renewable heating. For government, it was a way to build a market: to get installers trained, products certified and supply chains established before the wider transition away from fossil heating. Both of those aims are visible in the statistics the scheme produced, which tracked not just installations but also compliance, heat output and payments, year by year.

Two schemes: domestic and non-domestic

The RHI was actually two schemes with different rules, different payment periods and different reporting. The consultation that established the programme named them plainly: Domestic RHI and Non-Domestic RHI¹¹.

The non-domestic scheme came first. It opened in November 2011¹³ and was a 20-year inflation-linked subsidy for renewable heat installations in industrial, commercial and public sector settings, including district heating¹³. The domestic scheme followed in April 2014⁸, paying households quarterly for seven years rather than over two decades. The domestic scheme was later extended by two years beyond its originally planned end⁹.

The two schemes also differed sharply in scale and character. The non-domestic RHI was dominated by larger biomass installations, while the domestic scheme ended up dominated by heat pumps. An illustration of how slowly the early market grew: in non-domestic situations, for the period between November 2011 and September 2014 there were five applications for air source heat pumps across the whole of Great Britain¹⁴. The domestic scheme's 117,203 accreditations⁴ represent a far larger number of households, but spread over eight years and four technologies.

Both schemes are now closed: the non-domestic RHI closed in March 2021 and the domestic scheme followed on 31 March 2022⁸. Payments to existing participants continue under the original terms, which is why Ofgem still publishes annual reports on a scheme that takes no new applicants.

Key figures: uptake, output and money paid out

The most recent annual report puts the domestic scheme's totals at 117,203 accredited installations and around 10,745 GWh of heat generated since the start of the scheme⁴. An earlier report, covering the scheme to March 2024, recorded an estimated 8.84 TWh of renewable heat since 2014¹⁵, and the Scheme Year 11 report gives the lifetime figure as 10.1 TWh of estimated heat generation in domestic properties since 2014⁵. The numbers rise over time because accredited systems keep generating, and keep being paid, long after the scheme closed to newcomers.

Payments tell the same story of a scheme that grew steadily and then wound down. In Scheme Year 10 (April 2023 to March 2024) payments totalled approximately £114 million, taking payments since the start of the scheme above one billion for the first time, to £1,057,331,255⁶. In Scheme Year 11, almost £106.2 million was paid out⁵, and the lifetime total by technology stood as follows⁵:

The pattern is worth reading closely. Air source heat pumps generated nearly half of all the heat but took 38 per cent of the money; biomass took 30.8 per cent of the money for 34.6 per cent of the heat; ground source heat pumps, the most efficient of the lot, generated only 16.7 per cent of the heat. Solar thermal was a marginal technology on this scheme, at 1.7 per cent of payments⁵. Government guidance published in the Warm Homes Plan technical annex has since rounded the total to £1.2bn of payments since 2014⁷; the exact figure in the table above is the more precise, later count.

The scheme also subsidised 811.4 GWh of renewable heat generation in domestic properties in Scheme Year 10 alone¹⁵, so the annual run rate in its final years was still substantial even as new accreditations had ceased.

The way the scheme paid households

The domestic scheme's payment structure was simple in outline: people who joined and followed the scheme rules received quarterly payments over seven years for the renewable heat their systems were expected to produce⁹. Ofgem's guidance puts it as payments made every three months for up to seven years, the "tariff lifetime", from the application date¹⁰.

The amount was not based on what a system actually produced, in most cases. Payments for most installations were based on the annual heat demand of the property, taken from its Energy Performance Certificate (EPC)⁶. Ofgem's tariffs and payments guidance states it directly:

The exceptions were solar thermal installations, paid on the basis of the MCS certificate, and metered installations⁶. This is an important point for anyone reading the RHI statistics: the heat figures in the official reports are largely modelled from EPC heat demand, not measured at the meter, except where metering applied.

Tariff rates were set by the Department for Energy Security and Net Zero, and Ofgem acted as scheme administrator, responsible for publishing the current rates and making the payments¹⁰. Participants had to comply with a number of ongoing obligations during the seven-year accreditation to continue receiving payments¹⁶, which is where the scheme's audit programme, discussed below, came in.

The contrast with the non-domestic scheme was stark: a 20-year inflation-linked subsidy¹³ against a fixed seven-year domestic tariff lifetime. The domestic design traded long-term security for a quicker, simpler offer to households.

Eligible technologies and the certification requirements

Only four renewable technology types were eligible for the domestic scheme¹⁷:

• Biomass only boilers, and biomass pellet stoves
• Air source heat pumps
• Ground source heat pumps
• Flat plate and evacuated tube solar thermal panels

The essential guide lists them as air source heat pumps, ground and water source heat pumps, biomass boilers and stoves, and solar thermal in liquid-filled flat plate or evacuated tube form¹².

Certification was the gatekeeper. To be eligible, a renewable heating system had to be issued with an MCS certificate by the installer, and certificates could only be issued for systems using an MCS certified product¹⁷. The eligible technology had to be installed and commissioned by an MCS certified installer who could provide that certificate¹⁶. A parliamentary research briefing makes the wider point: the Feed-in Tariff, the Renewable Heat Incentive and the Smart Export Guarantee all require the renewable energy product and installer to be certified and meet MCS standards¹⁸.

This certification requirement is one of the RHI's most durable legacies. It built the MCS installation base that later schemes inherited, and it is why today's MCS installation statistics and the heat pump installation statistics can be compared with the RHI record at all. For installing renewable technologies including heat pumps, there are currently six registered competent person schemes: APHC, BESCA, Certsure, HETAS, NAPIT and OFTEC¹⁹. Installation contractors must be certified by MCS and install MCS certified products to qualify for government incentive schemes such as the Renewable Heat Incentive²⁰.

Two further conditions applied. Biomass used in renewable heat installations had to meet a set of sustainability criteria²¹. And from 2018, metering for performance was introduced for heat pumps⁹, a response to the gap between modelled and actual output that the EPC-based payment design otherwise left unexamined.

Performance against the scheme's own targets

By its own government's assessment, the RHI fell well short of what was promised. The Public Accounts Committee reported in 2018 that the Department had had to cut back its expectations of how much renewable heat would be produced by the scheme by almost two-thirds, and of the reductions in carbon emissions due to the scheme by almost half².

The domestic scheme's own numbers show a scheme that grew slowly and never reached mass deployment. 117,203 accredited installations over eight years⁴ is a small fraction of Britain's housing stock, and the quarterly deployment data shows the pipeline drying up entirely once closure approached: zero domestic RHI installations were recorded in 2024 Q3²² and zero in 2025 Q1²³, with the heat pump deployment statistics confirming the domestic RHI column at zero in each recent quarter²⁴.

Compliance was a second measure of performance, and the audit results were mixed. In Scheme Year 10, statistical desk audits found an 87.56 per cent compliance rate and statistical site audits 85.75 per cent⁶. But targeted audits, which select participants where problems are suspected, told a different story: a 62.00 per cent compliance rate on targeted site audits and just 42.50 per cent on targeted desk audits in the same year⁶. In Scheme Year 11, statistical audits ran at a 90 per cent confidence level to provide a representative view of the scheme⁵, with 421 desk audits at 85.04 per cent compliance and 389 site audits at 69.41 per cent⁵. The targeted programme in Scheme Year 11 conducted 189 site audits with a 57.67 per cent compliance rate⁵.

For a household reading these numbers, the lesson is that a subsidy paid on modelled rather than measured output, with obligations attached, invites both honest error and gaming, and the regulator knew it.

Flaws in the scheme and concerns raised

The Public Accounts Committee's 2018 report was blunt on the scheme's fundamental weakness:

This was the core design problem: a scheme that repaid its costs over seven years still required the household to find the capital first. The same report noted the cut-back expectations on both renewable heat output and carbon savings².

The audit findings added a second tier of criticism. In Scheme Year 11, the most common material non-compliance was "evidence not provided", with 30 instances (15.2 per cent), followed by "ineligible metering performance" with 29 instances (14.7 per cent); "evidence not provided" also led non-material non-compliance at 28 instances (14.2 per cent)⁵. These are not exotic failures: they are paperwork and metering problems, the everyday friction of a scheme that paid on estimates and then checked.

A third criticism was structural. Paying on EPC heat demand rather than measured heat meant the scheme had limited visibility of whether the renewable heat it paid for was actually being delivered, until metering for performance was introduced for heat pumps in 2018⁹. And the biomass sustainability criteria²¹, while necessary, added administrative weight that fell on participants, particularly in rural areas where biomass was the practical off-gas option.

The end of the scheme and its aftermath

The non-domestic RHI closed in March 2021⁸, and the domestic RHI closed to new applicants, including metering and monitoring service package applications, at midnight on 31 March 2022²⁵. The Scottish Government's heat buildings strategy had set out the same timetable: the non-domestic RHI due to close in March 2021 and the domestic RHI in March 2022²⁶.

Closure did not end the payments. Existing participants continue to receive quarterly payments for their full seven-year accreditation, subject to ongoing obligations¹⁶, which is why the domestic scheme was still paying out almost £106.2 million in Scheme Year 11⁵, three years after it shut to newcomers. Government spending on the schemes is visible in the departmental transaction data: a payment of £9,312,975 for RHI domestic AME payments on 1 July 2024 and £79,359,757 for RHI non-domestic AME payments the following day²⁷.

What replaced the RHI was a different philosophy: upfront grants rather than income streams. Heat pump installations are now supported through the Boiler Upgrade Scheme, which pays a grant at the point of installation rather than reimbursing over seven years. The Warm Homes Plan technical annex, in reviewing the history, notes that since 2014 the Renewable Heat Incentive has to date made £1.2bn of payments⁷. The RHI's slow, obligation-heavy design was judged to have held uptake back; the successor scheme trades the audit trail for speed.

Moving house when your system is accredited

Because RHI payments run for seven years and attach to the property's heating system, sales were a defined process rather than an informal handover. The seller had to contact Ofgem at least 28 days before the sale went through²⁸. The DRHI accreditation could be transferred to the new owner²⁸, and where the new owner applied for accreditation themselves, they had to do so within 12 months from the date of sale²⁸. Ofgem's participant guidance confirms the same 28-day notification requirement²⁵.

The practical implication for anyone buying or selling a home with an accredited heat pump, biomass boiler or solar thermal system is that the payments are an asset with strings attached. The ongoing obligations that apply during the seven-year accreditation¹⁶ pass with the system, so a buyer inherits both the quarterly income and the compliance duties, including any metering requirements. A household considering such a purchase can check the accreditation details with Ofgem before committing.

Finding and understanding the government data

The RHI statistics come from two publishers, and knowing which is which matters when checking a figure.

Ofgem, as administrator, publishes the annual and quarterly reports on the domestic scheme. The annual reports present the latest statistics on accreditations on the scheme, payments made, renewable heat generated, carbon dioxide saved and feedback from the customer survey²⁹, with later editions covering accreditations, payments made and renewable heat generated³⁰. The quarterly reports cover accreditations, payments and customer survey feedback³¹, and the series runs from the earliest issues³² through to the final scheme years. The most recent annual report covers April 2025 to March 2026⁴.

The Department for Energy Security and Net Zero publishes the deployment data: monthly statistics presenting the number of applications and accredited installations on the scheme so far, broken down by technology type and GB region and application status³³. The monthly releases detail applications and accredited installations on the non-domestic and domestic schemes³⁴, and the January 2021 release carries Official Statistics status³⁵. From March 2016 the release included quarterly data previously published separately, and quarterly reporting was introduced with effect from July 2022³³. The Renewable Heat Premium Payments figures were dropped from the release from January 2015³³. The underlying deployment dataset is published on data.gov.uk³³.

Two cautions when reading these series. First, check the data cut-off: the heat pump deployment statistics state their data is as of March 2024, in line with the RHI official statistics²³, so a figure quoted from a deployment table may lag the latest Ofgem annual report. Second, the heat figures are largely estimated from EPC heat demand rather than metered⁶, so "heat generated" in the RHI reports means "heat the scheme paid for on the modelled estimate". Our guide to reading energy statistics covers revisions and official status in more depth, and the official statistics publications page lists the release calendar.

Lessons from the RHI for self sufficient homes

The RHI's statistics matter today for three reasons.

First, they are the baseline. Any claim about how fast UK heat pump deployment is accelerating starts from the RHI years, and the deployment tables now show the domestic RHI column at zero²² while the Boiler Upgrade Scheme and the wider MCS installation statistics carry the growth. The RHI put 117,203 renewable heating systems into British homes⁴, and the certification infrastructure it required¹⁸ is the same infrastructure every later scheme and every household installation now runs on.

Second, the scheme's failures are as instructive as its successes. The Public Accounts Committee's finding that the scheme did not work for households unable to pay high upfront costs² shaped the shift to upfront grants. The audit record, with targeted site audit compliance at 57.67 per cent in Scheme Year 11⁵, is a reminder that subsidy schemes with ongoing obligations place real administrative weight on participants.

Third, for the households still receiving payments, the RHI is a live financial relationship with Ofgem, not history. Payments continue quarterly for the full seven years⁹, obligations continue with them¹⁶, and a sale triggers the 28-day notification and transfer process²⁸. The 10.1 TWh of estimated heat generation in domestic properties since 2014⁵ represents a large stock of homes whose heating is partly insulated from fossil fuel markets, though still dependent on electricity supply for heat pumps, on fuel supply chains for biomass, and on Ofgem's administration for the income itself. That is the honest picture of what the scheme achieved: a meaningful step toward household energy independence, paid for slowly, checked unevenly, and still being counted.