Scotland’s varied housing stock with a prevalence of traditional architecture means we will need to develop more innovative approaches to cut home heating emissions - and time is of the essence.
For Scotland to reach its target of net zero by 2045 will require an urgent reduction in the carbon emissions produced by our homes and buildings. For this to be possible, the vast majority will need to have a low-carbon heating system installed which will require multiple approaches and collaboration between the public and private sectors, industry and households.
In its Programme for Government 2021-22, the Scottish Government has set aside £1.8 billion over the next five years to make homes easier and greener to heat, including a minimum of £465 million to support those least able to pay for home energy improvements. Other promised measures include a public communication programme to encourage home upgrades and raise awareness of the support and advice available.
In recent weeks, both Ofgem and Scottish Development International have also made the case for innovative approaches to achieve our decarbonisation ambitions. It is encouraging to see a growing awareness of the scale of the challenge.
Decarbonising the way we heat our homes in Scotland is an essential step towards our net zero target and we must make the change at pace if we are to have any hope of meeting it. The Scottish Government’s own commitment is to decarbonise the heating of at least 1 million homes, and the equivalent of 50,000 non‑domestic buildings, by 2030.
Nesta’s strategy to 2030 sets out our ambition to help cut emissions from all UK households - which make up 15 per cent of total greenhouse gas emissions across the country - by looking at ways to decarbonise our home heating. To achieve this we want to accelerate the installation of ground and air source heat pumps in as many homes as we can.
However, in Scotland our built environment poses unique challenges. Due to a mix of architectural heritage and poor energy efficiency in older housing stock, installing heat pumps at sufficient scale in Scotland will only be feasible with considerable preliminary work to prepare our homes for a different way of keeping warm. To decarbonise the majority of Scotland’s 2.5 million homes will require researching and testing different solutions entirely.
As part of our early explorations for our sustainable future mission in Scotland, challenges to installing heat pumps became clear, some general and some unique to Scotland. Nesta’s recent Decarbonising Homes report, which looked at consumer attitudes towards energy efficiency and green heating, found a huge value-action gap exists across the UK between people’s belief in the urgency of the climate emergency and their readiness to change their behaviours. Furthermore, the cost and knowledge barriers to installing low-carbon home heating apply across the UK as does the likelihood of high running costs in some dwelling types due to poor energy efficiency.
However, some of Scotland’s architecture such as traditional tenement buildings, which include medieval, Georgian, Victorian and Edwardian examples, pose specific issues. Tenements make up 28 per cent of Scotland’s urban housing stock and are a world-renowned architectural feature across our cities. They are recognised in the UNESCO World Heritage status granted to Edinburgh’s Old and New Towns. Built with solid wall construction that is difficult to insulate, they typically remain uninsulated and difficult to heat.
Older housing stock such as tenement blocks would require substantial and costly energy efficiency measures including to the fabric of the buildings (which is often prohibited by current planning restrictions), in order for low-carbon heating alternatives such as heat pumps to deliver an acceptable standard of comfort at an affordable price. Any efficiency improvements would also need to navigate the complex shared ownership regulations and listed building status of most tenement properties, as would the siting of a heat pump on the exterior of the building or in a communal garden.
Mains gas, which currently makes up approximately 80 per cent of Scottish household heating fuel, is a very effective way to heat poorly insulated and draughty homes. Moving away from non-renewable heating is necessary to reduce carbon emissions, but inconvenient and currently very expensive.
How to Heat Scotland's Homes
You can read the specific findings from our exploratory work with Energy Systems Catapult including detailed modelling for heating a tenement flat in different heating upgrade scenarios.
Adapting Scotland’s homes away from our reliance on gas towards low-carbon alternatives will need multiple solutions. What replaces the gas boiler will likely be different in different homes and in different parts of the country. For some, the low whirr of a heat pump may replace the hum of a boiler, for others ceiling-mounted infrared panels may warm the objects and people in the room, rather than the air. For others still, new payment models or communal heat sources such as heat networks may help us to cut our emissions. Or perhaps we will find other ways to heat our homes with renewable energy that are cost effective and simple to install over the next ten years.
Nesta’s history and experience in innovation tells us that designing, trialing and measuring the effectiveness of multiple solutions requires knowledge, experience and insight from across different disciplines and sectors.
Throughout our 10-year mission, we intend to work in collaboration with partners from the heating, energy, construction and housing sectors, and with communities and householders, to test, develop and scale approaches that will work across Scotland’s homes so we can all benefit from the necessary shift to decarbonised heating.
As Glasgow prepares to host COP26, the eyes of the world will be on Scotland and the rhetoric of politicians from across the globe will be about urgency and the need to work together. When it comes to something as fundamental as how we stay warm in our homes, we have an obligation, and an opportunity, to turn that rhetoric into joined-up action.