A new batch of Census 2021 data on housing has just been released, giving us a chance to see how homes across England and Wales are heated.

Beyond being able to see whether homes have central heating or not - and whether they rely on gas, electric, oil or solid fuel – there was an option for households to report if they were heated by “renewable” sources such as a heat pump, or by district heating networks for the first time this year.

The data tells a familiar story – gas central heating is the most common heat source in most parts of England and Wales. But the data also shows the diversity of heating systems used in homes, especially in areas without access to the gas grid. In areas where gas is less common – including some rural areas and central London – there is a mix of heating systems, including oil and direct electric heating as well as renewables and heat networks. These areas seem to have experienced the most innovation in renewable heating, but also often have high shares of homes with direct electric heating, which can be extremely expensive and is often linked to fuel poverty.

Most households are heated using gas central heating only, but there are 18 local authorities where over half of households are heated differently

Most households in England and Wales (74%) reported that they use gas central heating as the only way to heat their homes; this is down from 78% in 2011.

There were 18 local authorities where half or less than half of households reported that they were heated by mains gas only. These are mainly concentrated in central London and in rural areas such as East Anglia, Devon, Cornwall and West Wales. In London, only 27% of households in the City of London were heated by mains gas, for example, while it was 48% in Tower Hamlets. In both boroughs, the higher reliance on direct electric heating seems to be the reason why mains only gas use is lower. Some parts of London do rely much more on gas though: in Richmond Upon Thames, as many as 80% of households reported that they were heated by mains gas only.

Outside London, the local authorities with the lowest share of gas connections include Ceredigion and Powys (West Wales), islands such as the Isles of Scilly and Anglesey, Eden (Cumbria) and rural parts of Norfolk and Suffolk.

Where are the greatest share of homes heated by renewable energy?

In total, only 98,730 households in England and Wales said their central heating was powered completely by renewable energy, such as heat pumps. A further 134,650 had multiple sources of central heating that included renewables, but both figures each represent less than 1% of all households.

These figures broadly tally with the MCS data on installations of heat pumps and other renewable heating sources in England and Wales, although it is hard to be sure given the broader category of “renewable” heating used in the census. We estimate that there are just under 250,000 heat pumps in England, Wales and Scotland, and that heat pumps are by far the most common renewable heating system.

A number of local authorities with the lowest shares of mains gas heated homes were in the top ten for centrally heated homes using renewable energy only. Cornwall stands out as a local authority with a lower share of mains-only heated homes (47%), and it’s the local authority with the seventh highest share (2%) of homes heated by renewables only.

Five local authorities in the top ten for share of households heated by renewable energy only were also in the top ten for share of households using multiple sources that included renewable energy.

Within local authorities, the concentration of renewable only-heated homes varies greatly

At the second lowest level of geography available in the census, Lower Layer Super Output Areas (LSOAs), some places record over 10% of households heated by renewables only, compared to others in the same local authority that have none.

Zooming into local areas even further using the tool published by the ONS allows comparison by Output Areas (OAs) – comprising 40 and 250 households with a resident population between 100 and 625 persons. It almost allows you to compare street by street and will make future analysis of the takeup of renewables by household income, area deprivation or other metrics possible. We believe this is the first time that technologies such as district heating have been mapped down to this local level.

Where is district heating taking off?

District heating, or heat networks, distribute heat or cooling from a central source or sources, and deliver it to a variety of different customers including homes. In the 2011 census, homes heated by district heating would have been covered in the ‘other’ bracket. This year, it is possible to see where district heating heats the highest share of homes. Unsurprisingly, district heating is located most prominently in urban locations, with London leading the way.

Many local authorities are at the beginning of their heat network journey – so homes being built are not yet occupied, meaning they won’t show up in census data.

A high share of households reported that they use only electricity to heat their homes, putting more people at risk of fuel poverty

In 2011, 8% of households said they heated their homes with electric central heating systems (including storage heaters). In 2021, this number was steadywith around 9% of households reporting that they used electricity only.

From this year’s census, electricity is the third most common way that households heat their homes. Yet BEIS data from the Heat and building strategy has only 5% of homes using electric storage heating. This is concerning for a number of reasons. In 2020, BEIS data covering England found that households that used electricity to heat their homes faced higher fuel costs than for all main fuel types. This is because direct electric heating typically uses a similar amount of energy to a gas or oil boiler, but electricity is much more expensive. With electricity prices in the UK jumping by 65.5% in the 12 months to November 2022, these households’ bills are set to skyrocket. Another concern is that electricity-heated households are more likely to be fuel poor, meaning their disposable household income falls below the poverty line after paying for energy and housing costs, and they have a low EPC rating.

Why we need a radically different picture by the time of the next census

Nesta’s mission is to reduce household emissions by 30% from 2019 levels by 2030. Changing how people heat their homes is one of the most effective things that the UK could do to cut pollution.

The 2021 census reveals an unsustainable mix of heating solutions, mostly based on fossil fuels, and this will need to change in order to meet net-zero targets. To meet these targets, we need to carry out green upgrades in millions of homes in the next three decades. The UK lags behind many of its European neighbours, who have shown that a faster transition is possible. By the time of the next census in 2031, we hope to see the map tilting far more in favour of renewable energy. You can find out more about what we’re doing at Nesta to make that happen.