The inability of people across the UK to heat their homes adequately could make the nation’s reduction of carbon emissions more difficult to achieve than previously thought, according to research at the University of Strathclyde.
The newly-published study finds that, for similar dwelling characteristics, financially challenged households use far less energy to heat their homes, and the end-use heat demands of households with electric storage heaters is half as much as of those heated with natural gas.
Although there are many possible social and economic causes, the authors suggest that lower-income households dependent on conventional electric heating are under-heating their homes, with the potential for increased prevalence of related health problems. This creates the opportunity for the drive for low-carbon heating to also improve the living standards of financially-challenged households. Provided the challenge of the high capital cost of low carbon heating can be addressed, and help provided with home insulation, the reduction in heating-related carbon emissions can contribute significantly to reduction in fuel poverty.
Jack Flower, a PhD candidate in Strathclyde’s Centre for Doctoral Training in Future Network and Smart Grids, is lead author of the study. He said: “Policy makers across the UK are rightly prioritising the residential heat sector as a major target for emissions reduction but our work shows the importance of understanding how fuel poverty must be tackled in tandem with that.
“Although this study highlights that the challenge in meeting our Net Zero goals may be even harder than we thought, we must keep in mind the importance of a well-constructed heat policy in improving people’s comfort, welfare and health. The challenge of ensuring adequate comfort and health in people’s homes and making it affordable will be brought into sharp relief as we enter the first heating season of the COVID-19 pandemic.”
In order to meet the Net Zero target set by the UK Government in 2019, greenhouse gas emissions from heating homes – currently responsible for 14% of all national emissions – will need to be reduced to near zero by 2050 through the replacement of current heating technologies with lower-carbon options such as electric heat pumps. Such technologies are typically more expensive to install, but cheaper to run, than existing heating systems.
However, the study shows that if fuel-poor households are given access to lower-cost heating in this manner, their energy consumption is likely to increase in response, perhaps as much as doubling, in what is known as a ‘rebound effect’. This means that the reduction in carbon emissions in residential heating is likely to be more expensive to achieve than previously thought for certain households.
The study also found that the abatement cost of heat pumps – the amount of money that must be invested to achieve a certain amount of carbon emissions reduction – varies significantly according to both the size of household and the existing heat technology, and that the diversity which exists in the UK housing stock makes it difficult to recommend a single ‘one size fits all’ approach to reducing heat sector emissions. This diversity is highlighted as being potentially overlooked in current heat sector policy.
Because of this, high capital cost heat technologies, such as heat pumps, may not initially appear to be cost-effective based on certain cases of existing use of energy for heat – compared with options such as electric heaters with higher running costs but low installation costs. However, they may become so once the rebound effect and broader benefits are considered.
The study also highlights the importance of focusing current efforts on carbon-intensive homes off the gas grid which may be using fuel oil or solid fuels as their primary heating source.
Dr Graeme Hawker, a Research Fellow in the Department of Electronic and Electrical Engineering and a co-author, said: “Our study shows that, according to actual consumption data, the amount of energy used inside certain types of homes is likely to be more than we thought. However, the energy used by heat pumps to meet that demand is only a third of what would be required by electric storage heaters or gas boilers.
“It’s also critical that the insulation of the leakiest homes is dramatically improved to further reduce the amount of electricity that needs to be supplied and reduce bills.”
Jack Flower’s research is funded by the Engineering and Physical Sciences Research Council. Graeme Hawker’s research is conducted as part of the programme of the UK Energy Research Centre.
A third co-author of the study is Keith Bell, Professor in the Department of Electronic and Electrical Engineering and co-Director of the UK Energy Research Centre.