"BRE has worked closely with the government since SAP was introduced, and we are excited about the potential for ambitious policies and programmes for low-carbon homes which the latest version will support"
- Gillian Charlesworth - Building Research Establishment
The Standard Assessment Procedure (SAP) is the Government’s system for assessing and comparing the energy performance of homes. In regulation it is used in building regulations, to ensure new homes are energy efficient and low carbon and is used to generate Energy Performance Certificates which are required when all homes, new and existing, are sold or rented out.
SAP is also used more widely within and outside government, for example in government grant schemes, policy evaluations and to support advice to households on making energy efficiency improvements.
The Home Energy Model, which in development has been known as SAP11, will be more suited to the technologies required to decarbonise the country’s housing stock as we move towards net zero because it is a complete overhaul based on the next generation of software.
Created as part of a three-year research project with DESNZ, the Home Energy Model has been designed by BRE ahead of the implementation of the Future Homes Standard, which will apply to new homes built from 2025.
The Home Energy Model will be used to set standards for new homes to ensure that they will be ‘zero carbon ready’, future-proofed with low carbon heating and world-leading levels of energy efficiency. The Government has also signalled its intention to use the Home Energy Model to power assessments for Energy Performance Certificates.
BRE has given what was previously known as SAP a complete overhaul. The Home Energy Model is better suited to green technologies, such as heat pumps, storage technologies and smart control devices. It is designed to work in a modular way to support many different applications where energy performance assessments are required.
It has a higher time resolution and can model energy performance for every half-hour of the year, enabling a better representation of smart technologies and storage. The consultation proposes that the Home Energy Model will be released as open source, increasing transparency and making it easier for industry and researchers to apply and modify the methodology for different applications.
The Government consultation seeks views on the Home Energy Model while it is still at a formative stage. Responses to the consultation will inform its development before being implemented alongside the Future Homes Standard in 2025.
Gillian Charlesworth, Chief Executive of BRE, said: “The introduction of the Home Energy Model is a significant milestone on the road to achieving net zero across the UK’s housing stock.
"As uptake of green technologies increases, an effective assessment methodology which accounts for these changes will be imperative as the Government looks to secure buy-in from homeowners, housebuilders, and the retrofit industry on the net zero transition and achieve its targets in this area.
“BRE has worked closely with the government since SAP was introduced, and we are excited about the potential for ambitious policies and programmes for low-carbon homes which the latest version will support.
"These changes to the SAP methodology will have wide-reaching impacts not only for the government but across the industry. I therefore urge all relevant stakeholders to take part in this consultation to ensure that the final design of the Home Energy Model is as well informed as possible.”
