The scale of the challenge of decarbonising housing stock is significant. In 2023, 1.6 Mt CO2e of annual territorial greenhouse gas emissions were from domestic gas and electricity consumption in South Yorkshire. This was 25% of the total regional emissions in 2023.
Here we explore three more case studies from SYSC’s Consolidated Research Report exploring how and why the region could retrofit its homes at scale. This is in response to SYSC’s project titled Development of a regional retrofit optimisation platform which asked how can South Yorkshire prioritise the delivery of regional retrofit programmes to tackle property types that offer the best carbon savings.
Key Insights:
To meet regional and national net-zero targets, South Yorkshire must significantly accelerate its housing retrofit program, targeting between 19,200 homes for a 2050 net-zero target and 32,000 homes for a 2040 target annually. To maximise carbon savings, homes with higher operational energy demands, e.g. larger pre-1920s homes, should be prioritised. Using the Verisk GPS database, there are about 46,000 homes in South Yorkshire that are both above 100m2 and constructed pre-1919. While "system-first" approaches, where fossil fuelled heating systems (gas boilers) are replaced with electrified heating systems ( such a heat pump(HP)), can reduce emissions by 73%, they currently risk increasing energy bills by 10% due to electricity pricing, potentially worsening the 15% fuel poverty rate already affecting the region.
Our research confirms that the highest savings in both operational carbon emissions (96%) and energy bills (85%, heating temperature setpoint of 20°C) would be achieved with whole house retrofit deployment. Whole house retrofit is defined as replacing the central gas heating system with heat pumps and installing all insulation measures (wall, roof, floor) with high performance windows. When a full retrofit is financially unfeasible, a "fabric-first" approach is recommended in the immediate term. Prioritising insulation and glazing over heating systems alone yields higher emissions savings (85%) and protects residents from rising costs. However, this strategy must be balanced against embodied carbon; as the National Grid decarbonises toward 2040, the environmental "cost" of manufacturing insulation materials will eventually make system upgrades the more carbon-efficient long-term solution.
The environmental impact forecasting against the UK net-zero targets revealed that air-source heat pumps (ASHPs) are likely to achieve the largest carbon emission reduction over time (97% by 2050), while ground-source, water-source and hybrid-source heat pumps are expected to reduce by 94%, 95%, and 59%, respectively. Furthermore, installing heat pumps in thermally inefficient homes risks grid overload and increased consumer costs. Therefore, fabric improvements remain essential to manage peak demand and ensure that the transition to low-carbon heating does not compromise energy security or affordability for vulnerable communities.
View the case studies in full below
Read the case studies in full below:
