Heat in Buildings: progress report 2025
Annual update on progress against our Heat in Buildings Strategy and Monitoring and Evaluation Framework.
2. Outcomes
2.1. Outcome: reduced energy demand to buildings
2.1.1. Method: ensuring a good level of energy efficiency in domestic properties
2.1.1A Indicator: share of domestic properties achieving a good level of energy efficiency (currently equivalent to Energy Performance Certificate (EPC) C or better):
- share of owner-occupier properties
- share of private rented sector properties
- share of social rented sector properties
Data source: Scottish House Condition Survey (SHCS)
Unit: per cent
Most recent data: 2023
| Year | 2019 | 2022 | 2023 |
|---|---|---|---|
| Share of owner-occupied properties (%) | 41 | 48 | 51 |
| Share of private rented sector properties (%) | 40 | 50 | 52 |
| Share of social rented sector properties (%) | 56 | 65 | 69 |
Commentary:
The percentage of dwellings achieving an EPC rating of at least C under SAP2012 (RdSAP v9.93) has increased across all tenure types between 2019 and 2023. 2019 is included as a baseline, with 2022 also included. Due to the COVID-19 pandemic, fieldwork for the 2020 SHCS was suspended and the methodology for the 2021 SHCS was also affected.
The percentage of owner-occupied dwellings achieving an EPC rating of at least C increased from 41% to 51% (from 2019 to 2023). The percentage of private rented sector dwellings achieving an EPC rating of at least C increased from 40% to 52% (from 2019 to 2023). The percentage of social rented sector dwellings achieving an EPC rating of at least C increased from 56% to 69% (from 2019 to 2023). See indicator 4.2.1(A) for more details about proposed regulations to significantly improve the energy efficiency of Scotland’s homes.
2.2. Outcome: increased supply of clean heat to buildings
2.2.1. Method: uptake of low emissions heating and clean heating in domestic properties
2.2.1A Indicator: number of domestic properties currently with clean heating systems:
- heat pumps
- connected to a heat network
- other electric heating
Data source - heat pumps and electric heating: Scottish House Condition Survey (SHCS)
Data source - heat networks: Heat Networks Metering and Billing Regulations (HNMBR) data
Unit: number of domestic properties
Most recent data[2]:
- heat pumps: 45,000 (around 1.9% of all dwellings)
- connected to a heat network: 27,900 (around 1.1% of all dwellings)
- other electric heating: 221,000 (around 8.7% of all dwellings)
| Year | 2019 | 2022 | 2023 |
|---|---|---|---|
| Heat pumps | 23,000 | 34,000 | 45,000 |
| Heat networks | 27,900 | ||
| Other electric | 242,000 | 241,000 | 221,000 |
Commentary:
The number of dwellings with a heat pump or other electric heating in 2023 is statistically like 2022, the last year for which comparable data are available[3]. However, the 2023 heat pump figure represents an increase over 2019. The latest edition of the HNMBR dataset does not extend beyond 2022, and so the 2022 figure is based on the most recent available data. The number of properties connected to a heat network for 2022 is based on HNMBR notification data spanning 2014 to 2022[4]. The estimate relies on limited data with concerns about its quality, including known inconsistencies in the way that heat network operators have reported customer connections in the HNMBR data, such as listing a local authority or housing association as one customer (as opposed to listing each property within either that they are supplying). The number of domestic connections is therefore likely to be an underestimation. Indicator 4.2.1(A) includes further details about the Scottish Government’s proposed regulations to scale up the installation of clean heating in Scotland’s homes.
2.2.1B Indicator: number of domestic properties recently installing a clean heating system:
- heat network connections (four-yearly connections data)
- heat pumps (annual installations)
- other electric heating (annual installations)
Data source - heat pumps: Microgeneration Certification Scheme (MCS)
Data source - heat networks: HNMBR data
Data source - other electric heating: no data source currently
Unit: number of properties
Most recent data[5]:
- heat pumps (annual installations): 7,355
- heat network connections (data spanning 2018-2022[6]): 3,687
- other electric heating (annual installations): N/A
| Year | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|
| Heat pumps | 2,193 | 2,441 | 4,246 | 4,952 | 6,294 | 7,355 |
Commentary:
Data for the last full calendar year (2024) indicate that the number of heat pumps installed per year in Scotland has more than tripled since 2019, and increased by 17% in 2024 compared to 2023. MCS data are published on the MCS dashboard in real time and indicates the number of heat pumps installed in Scotland between August 2024 and July 2025 as 6,861. This figure is slightly lower than the same period the previous year, with 7,254 heat pumps installed between August 2023 and July 2024.
As above, the latest edition of the HNMBR dataset does not extend beyond 2022, and so the 2022 figure is based on the most recent available data. The heat networks figure is based on the latest HNMBR data cycle (2018-2022) and includes connections to new heat networks (i.e. those which were completed within the previous four years). It does not include new connections to existing heat networks; therefore this figure may be an underestimate. The data limitations of the HNMBR data source described in the commentary at 2.2.1A are also relevant to this indicator.
We do not currently have a reliable data source for the number of other electric heating systems installed each year.
2.2.1C Indicator: number of domestic properties with low emission or low emission ready heating systems, such as:
- biomass boilers
- combined heat and power (CHP)
- fuel cells
- hybrid heat pumps
- hydrogen-ready boilers
Data source - biomass boilers, CHP: SHCS
Data source - fuel cells, hybrid heat pumps and hydrogen-ready boilers: no data source currently (not currently covered by SHCS but could in future if these systems become more prevalent).
Unit: number of properties
Most recent data (2023):
- biomass boilers: 10,000
- CHP: 6,000
- fuel cells: N/A
- hybrid heat pumps: N/A
- hydrogen-ready boilers: N/A
| Year | 2019 | 2022 | 2023 |
|---|---|---|---|
| Biomass | 16,000 | 12,000 | 10,000 |
| CHP | 9,000 | 6,000 | 6,000 |
Commentary:
Latest data (2023) indicate that around 10,000 Scottish homes (around 0.3% of all dwellings) use biomass as their primary heating fuel. As well as biomass boilers, this includes those using a wood burning stove as their primary heating source. There are an estimated 6,000 homes using combined heat and power (CHP) (around 0.2% of all dwellings). This is similar to 2022, the last year for which comparable data are available.
The SHCS data do not currently record all low emission or low emission ready heating systems, such as fuel cells, hybrid heat pumps and hydrogen-ready boilers, but it may be possible to do so in the future.
2.2.1D Indicator: percentage of new domestic properties with clean heating system completed in the last year:
- with heat pumps
- connected to a heat network
- with other electric heating
Data source: EPC register
Unit: per cent
Most recent data (2024)[7]:
- with heat pumps: 19%
- connected to a heat network: 6%
- with other electric heating: 8%
| Year | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|
| Heat pumps | 10% | 12% | 11% | 13% | 14% | 19% |
| Heat networks | 4% | 2% | 5% | 6% | 6% | 6% |
| Other electric | 2% | 2% | 3% | 2% | 6% | 8% |
| Total | 16% | 16% | 20% | 21% | 26% | 33% |
Commentary:
In 2024, 33% of new domestic buildings are estimated to have clean heating. This is an increase compared to 2023, when 26% are estimated to have clean heating. In 2019, 16% of new domestic buildings are estimated to have clean heating.
The New Build Heat Standard (NBHS) currently means that no new buildings constructed under a building warrant applied for from 1 April 2024 will have heating systems such as gas and oil boilers, and will be built instead with alternatives, like heat pumps and heat networks. However, there will still be new buildings built with polluting heating systems over the next few years where they are based on a building warrant that was approved prior to this date. Therefore we would expect to see the percentage of new domestic properties with clean heating systems increase significantly over the next few years.
2.2.2. Method: uptake of low emissions heating and clean heating in non-domestic properties
2.2.2A Indicator: number of non-domestic properties currently with clean heating systems:
- heat pumps
- connected to a heat network
- other electric heating
Data source - heat networks: HNMBR data
Data source - heat pumps and other electric heating: Non-Domestic Analytics v2 (NDA)
Unit: number of properties
Most recent data:
- heat pumps (2025 data[9]): 29,030 (12.2%)
- connected to a heat network (data spanning 2018-2022[10]): 2,450
- other electric heating (2025 data[11]): 97,760 (41.2%)
Commentary:
Data for heat pumps and other electric heating are from NDA, a database produced by Energy Saving Trust on behalf of the Scottish Government to provide a comprehensive resource on the non-domestic building stock in Scotland. We only present the data from the latest version of the dataset, which includes data up to February 2025. This is because later editions include improvements to the methodology and data sources which means that it is not comparable with previous NDA data.
NDA brings together various sources of data on non-domestic buildings and uses statistical models to help fill data gaps in the underlying data sources. This is challenging due to considerable variation in the types and purposes of non-domestic properties, as well as a lack of detailed information on their characteristics and poor coverage of existing datasets. For example, around one fifth of properties within NDA dataset have an EPC record. We are continuing to explore options to fill this data gap, including working with key stakeholders to develop and enhance data sources.
The previous progress report indicated a higher figure for heat pumps due to changes in the methodology for identifying properties with a heat pump. The figure above only includes those properties in NDA v2 where a heat pump is the main heating system (based on EPC information supplemented by modelled data to fill gaps). The previous method included properties where a heat pump was a secondary heating system and further modelling to predict the presence of a heat pump which resulted in higher estimates.
As mentioned previously, the latest edition of the HNMBR dataset does not extend beyond 2022, and so the 2022 figure is based on the most recent available data. The number of properties connected to a heat network in 2022 is based on HNMBR notification data spanning from 2014-2022. As with the domestic heat network connections, due to the known inconsistencies with the way that heat network operators have reported customer connections within the HNMBR data, the number of non-domestic connections is likely to be an underestimation.
2.2.2B Indicator: number of non-domestic properties recently installing a clean heating system:
- heat pumps (four-yearly figure)
- heat network connections (four-yearly figure)
- other electric heating (annual figure)
Data source – heat pumps: Renewable Heat Database (RHD)
Data source – heat networks: HNMBR data
Data source – other electric heating: no data source currently
Unit: number of properties
Most recent data:
- heat pumps (four-yearly figure): 970 (2021-2024)
- heat network connections (four-yearly figure): 177 (2018-2022)
- other electric heating (annual figure): N/A
Commentary:
The figure for heat pumps uses data from RHD, a database produced by Energy Saving Trust on behalf of the Scottish Government to provide a comprehensive resource on renewable heat installations in Scotland. The RHD brings together information from MCS, Non-Domestic Renewable Heat Incentive, Combined Heat and Power Quality Assurance Scheme (CHPQA), and other datasets.
This has been presented as a four-yearly figure because there may be a time delay between installations becoming operational and being captured in the datasets noted above, and an annual figure may not capture changes. The type of property is not always known due to there being information missing in the data sources that feed into the RHD. This means that the figure presented above is likely to be an underestimate of the number of non-domestic properties recently installing a heat pump. Around 2,000 other properties of unknown type have installed a heat pump over the same period (2021-2024), and some of these are likely to be non-domestic.
As above, the latest edition of the HNMBR dataset does not extend beyond 2022, and so the 2022 figure is based on the most recent available data. As with the domestic data, the estimate of new non-domestic connections to heat networks is based on the latest HNMBR data cycle (2018-2022) and includes connections to new heat networks (i.e. those which were completed within the previous four years). This figure may be an underestimate as it does not include new connections to existing heat networks.
With the amount of methodological development occurring in NDA, especially with the recent update to version 2 (including the use of OS National Geographic Database resulting in a drop in overall non-domestic stock), we are not able to report on this indicator based on comparing between versions of NDA at this stage. This is why we have continued to report this as a data gap, and continue discussions with EST around how we can address this in future. EST did provide some analysis for 2.2.2A and 2.2.2C which we have incorporated into the report.
2.2.2C Indicator: number of non-domestic buildings currently with low emission or low emission ready heating, such as:
- biomass boilers
- CHP
- fuel cells
- hybrid heat pumps
- hydrogen-ready boilers
Data source - biomass boilers: Renewable Heat Database
Data source - CHP: NDA and Combined Heat and Power Quality Assurance Scheme (CHPQA)
Data source - fuel cells, hybrid heat pumps and hydrogen-ready boilers: N/A
Unit: number of properties
Most recent data:
- biomass boilers (2024 data): 3,230
- CHP (2025 data[12]): 440
- fuel cells: N/A
- hybrid heat pumps: N/A
- hydrogen-ready boilers: N/A
Commentary:
The previous progress report used NDA to report on biomass; however, this included solid fuel boilers. To address this, we have decided to use the Renewable Heat Database (RHD) as this is the most comprehensive known installation database. However, this is still likely to be an underestimate of the number of properties with biomass boilers as there is a time delay for installations to be made known to the RHD. Also, as with 2.2.2B, the type of property is not known for all properties in the RHD. Around a further 3,000 properties of an unknown type have a biomass boiler and some of these are likely to be non-domestic.
For CHP, non-renewable installations from the CHPQA dataset have been added to CHP installations identified in the latest edition of NDA. This is because NDA only includes renewable CHP based on the EPC register and the RHD. Biomass CHP installations have been included in the CHP figure.
We are continually seeking to improve the quality and granularity of data on non-domestic buildings, including updates to the RHD and NDA, and working with the UK Government which is developing a National Buildings Database. We are currently unable to track the less common and newer technologies (fuel cells, hybrid heat pumps and hydrogen-ready boilers); however, we expect data on this to become available as non-domestic data develop and the deployment of these technologies increases.
2.2.2D Indicator: percentage of new non-domestic properties with clean heat completed in the last year:
- with heat pumps
- connected to a heat network
- with other electric heating
Data source: non-domestic EPC register
Unit: per cent[13]
Most recent data[14]:
- with heat pumps: 46%
- connected to a heat network: 2%
- with other electric heating: 26%
| Year | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|
| Heat pumps | 37% | 44% | 35% | 51% | 44% | 46% |
| Heat networks | 2% | 1% | 5% | 3% | 3% | 2% |
| Other electric | 19% | 19% | 17% | 14% | 26% | 26% |
| Total | 58% | 63% | 58% | 68% | 73% | 74% |
Commentary:
In 2024, 74% of new non-domestic buildings are estimated to have been built with a clean heating system. This compares to an estimated 58% new non-domestic properties being built with a clean heating system in 2019.
As with indicator 2.2.1D, because building warrants for new non-domestic properties will need to state that the property will be constructed with a clean heating system from 1 April 2024, we expect to see the percentage of new non-domestic properties with clean heating systems increase significantly over the coming years.
2.2.3. Method: rollout of zero emissions heat networks
2.2.3A Indicator: heat supplied by heat networks (statutory target to reach 2.6 Terawatt hours (TWh) by 2027, 6 TWh by 2030 and 7 TWh by 2035) to:
- domestic properties
- non-domestic properties
Data source: HNMBR data
Unit: TWh
Most recent data (data spanning 2014-2022):
- domestic properties: 0.46 TWh
- non-domestic properties: 0.75 TWh
- mixed (both domestic and non-domestic properties): 0.15 TWh
Commentary:
We estimate that a total of 1.36 TWh of heat was supplied via heat networks in Scotland in 2022[15].
This indicator relies on our best estimates on the supply of heat with the limitations of existing data currently available to us, with the latest edition of the HNMBR dataset covering up to 2022. These estimates are based on HNMBR notification data spanning from 2014-2022, aiming to provide an estimate on the whole known heat network sector in Scotland, including known networks that have not notified in the latest data cycle (2018-2022). Our estimate includes a breakdown by domestic and non-domestic properties as well as a mixed category that serves both property types. Our estimate relies on limited data with concerns about quality. This includes poor data coverage in key areas which required modelling to fill in the gaps, lack of information around decommissioning of networks, and issues surrounding enforcement of notifications. All of the above factors limit our ability to estimate the true size of the heat networks sector in Scotland or the total amount of heat supplied.
Indicator 4.2.1F provides details about the Scottish Government’s work to develop a regulatory regime to meet our heat networks statutory requirements, and which we believe will help provide improved data and more accurate reporting in future.
2.2.3B indicator: share of low carbon heat in existing heat networks
Data source: HNMBR data (share of fuel source and technology)
Unit: per cent
Most recent data (2022):
- Share of low carbon heat in existing heat networks: 11%
Commentary:
We estimate that by 2022 around 11% of existing heat networks in Scotland used low carbon heat as a fuel source. This includes heat networks which use electricity, biomass or biogas as their primary fuel.
These estimates are based on the HNMBR dataset with the latest edition covering up to 2022 and the same data limitations described above apply. A further limitation is that this assumes heat networks use only one fuel source. The fuel type of around 5% of heat networks is also unknown, meaning the above figure may be a slight underestimation.
We are not able to provide an estimate for earlier years that could be used as comparison for this indicator as the current estimate comes from a combined (and partially modelled) HNMBR dataset spanning 2014-2022, where the 2014-2018 dataset was used as a base and the 2018-2022 one used to update/refresh where appropriate. This means that the 2018 figure would not be suitable for comparison as it would come from a different dataset (2014-2018). The process of combining this data involved extensive quality assurance and cleaning due to known inconsistencies and networks not captured within the individual datasets.
We are in the process of trying to access an updated version of the HNMBR data, with the hope that this can be used in the next progress report, and we can hopefully find ways to make sensible comparisons on progress for this indicator (and others) in future.
2.3. Outcome: the heat transition is fair, leaving no one behind
2.3.1. Method: heat is affordable
2.3.1A Indicator: percentage of homes in fuel poverty (statutory target in 2040 no more than 5% of households are fuel poor with <1% in extreme fuel poverty)
Data source: SHCS
Unit: per cent
Most recent data (2023):
- Percentage of homes in fuel poverty: 34%
| Year | 2019 | 2022 | 2023 |
|---|---|---|---|
| Fuel poverty | 25% | 31% | 34% |
Commentary:
In 2023, 861,000 households (34% of all households) were estimated to be in fuel poverty. This is higher than the 2022 estimates (last available comparable data) of 791,000 households (31% of all households) and is largely driven by the increases in energy prices seen in 2023[16].
On 1 April, we published our first fuel poverty three-year statutory periodic report, outlining progress from 2021-24 towards tackling the four drivers of fuel poverty and meeting our statutory targets.
High energy prices have had the largest impact on fuel poverty rates. The levers to make a difference, such as energy price setting and market reform, lie with the UK Government. We continue to press for urgent action from the UK Government, including on proposals to reduce the current high price of electricity relative to gas. We are also pressing for a targeted bill discount that is available to all fuel users, offering transitionary protection to ensure that consumers can afford their current heating and energy needs, while supporting them to transition to clean heating.
2.3.2. Method: green heat jobs for the heat transition
2.3.2A Indicator: net change in heat and energy efficiency jobs
Data source: available data insufficient for monitoring
Unit: net change
Most recent data:
- N/A
Commentary:
The Office for National Statistics’ Low Carbon and Renewable Energy Economy (LCREE) survey provides annual estimates of the number of full-time equivalents (FTEs) across sectors including renewable heat, renewable CHP, energy efficient lighting and energy efficient products. LCREE also provides data at the ‘low carbon heat’ grouping. This survey estimates that, in 2023, there were 2,700 FTEs in Scotland working in low carbon heat (compared to 1,900 in 2022).
However, as with last year’s report, datasets are insufficient for monitoring purposes due to the wide confidence intervals around the estimates at the Scotland level, making it difficult to say whether year-on-year changes are statistically significant or not.
A Scottish Enterprise study in 2024[17] estimated that the Scottish clean heat sector consists of over 470 companies, with 8,300 direct employees. The sector has experienced significant growth over the past three years, with employment increasing by 68%.
We continue to work on just transition planning for the built environment and construction sectors. Ahead of developing a full Just Transition Plan, we are working on a range of projects and workstreams to improve the evidence base and just transition outcomes for the sectors. We have commissioned research through CXC to carry out workforce analysis of the construction sector out to 2045. This project will give us a better understanding of the construction skills and workforce requirements needed for a net zero economy. We are also working with the Construction Leadership Forum’s[18] Net Zero Working Group to develop a Construction Industry Net Zero Route Map, and will agree timescales shortly.
We include details about the Scottish Government’s work to support the scale up of the green heat supply chain at indicator 4.2.1C.
Contact
Email: heatinbuildings@gov.scot