The Future Homes Standard and Home Energy Model
Before Christmas 2023, the UK government published consultations on the Future Homes Standard and the Home Energy Model. Both are expected to go live in 2025. Thermal Storage UK recently responded to these important consultations which will impact how we decarbonise new and existing homes for years to come.
Future Homes Standard
Thermal Storage UK supports the introduction of the Future Homes Standard (FHS) to ensure that new homes are built as net zero homes. The FHS sets out the UK government’s commitment to electrifying heat, whether by connecting new homes to heat pumps or heat networks. The key criteria is that heating systems in new homes must be zero-carbon ready. Implementing the FHS would enable the UK to stop building houses that will later need to be retrofitted. It is a somewhat farcical state of affairs that new homes are still being connected to the gas network in 2024.
If implemented, the FHS is a good example of the government providing long-term certainty to builders and developers. By the time the FHS is fully implemented in 2026, developers will have had five years since building regulations were updated to require new heating systems to operate at 55C or below.
We have raised some specific concerns in our response relating to heat batteries:
The FHS could adopt a more technology-agnostic approach to hot water, rather than being designed with hot water cylinders in mind. In the absence of regulatory constraints, we expect heat batteries for hot water to increasingly take market share from traditional hot water cylinders. A heat battery for hot water is less than a third the size of the equivalent hot water tank, creating more space in homes for people to make use of. Heat batteries are an excellent partner for the heat pump installations that will dominate new builds once the FHS is introduced.
We encourage the FHS to allow developers to oversize the thermal store installed in a new build property to allow for flexibility. Oversizing may be considered where the thermal store is designed to provide flexibility to the electricity system, for instance working with a time-of-use tariff, as well as hot water or space heating. Every home fitted with a heat pump will have a thermal store - whether a heat battery or hot water cylinder - installed at the same time for hot water.
The FHS applies to material changes of use (MCU) which heat batteries for central heating could help to decarbonise. We encourage the FHS to allow for heat batteries for central heating in MCUs, particularly low-rise MCUs, to give developers the optionality of installing highly efficient heat pumps or highly flexible heat batteries. This would mean updating the proposed notional building specifications for MCU buildings.
We also recommend rebranding the “Future Homes Standard” as the “Modern Homes Standard” to futureproof the standard.
Home Energy Model
We agree with the need to update the Standard Assessment Procedure (SAP) which underpins the energy rating for new builds and existing homes. The Home Energy Model (HEM) promises welcome improvements on SAP. The proposed HEM will modernise the software infrastructure, enhance the granularity of the modelling and make it easier to add new technologies. We welcome incorporating heat batteries for central heating for the first time.
We have highlighted further enhancements in our response:
We recommend that the HEM incorporates heat batteries for space heating and domestic hot water from its inception in 2025. Heat batteries for hot water are an established product, working with heat pumps and other low carbon technologies.
The HEM could do a better job of considering flexibility from heating systems, thermal storage and electrical storage. The proposed use of a single Primary Energy Factor and carbon dioxide emissions underplays the intraday (and seasonal) variation in Primary Energy Factors and Carbon Factors for grid electricity.
We agree that the current Appendix Q process for new technologies is not fit for purpose. This includes a lack of transparency around the application process, financial and commercial risk for innovators, long timeframes and the lack of integration. We recommend central funding is available to support innovative SMEs taking new products through whatever replaces Appendix Q.
We, along with many other stakeholders, recommend that the HEM is developed through deep engagement with the heating, building and energy industries. We need an open and genuine engagement process so that companies can hit the ground running when the new processes start to come into force in just over a year’s time. This engagement would help to work through more technical issues such as ensuring that product characteristics are configurable in the Products Characteristics Database (PCDB) and that control algorithms are reflective of the level of self-learning, predictive and adaptive controls that are now the norm. Industry should proactively and diligently work with officials to ensure that the FHS and HEM are ready for go-live in 2025.
The consultations on the FHS and HEM are open until Wednesday 6 March 2024, so there is still time to engage with the relevant policy teams.