We’re pleased to share an important milestone for tepeo and the wider heat battery industry: the tepeo Zero Emission Boiler (ZEB®) has been added to SAP Appendix Q.
This means the ZEB can now be better represented in Energy Performance Certificate (EPC) assessments, helping homeowners achieve an improved EPC score.
We have been working for several years to get heat batteries recognised in SAP and EPC assessments, and this is a welcome step forward in recognising just how far heat storage technology has come.
After all, modern heat batteries are a world away from the electric storage heaters of the 1970s. And it’s important that the way we assess homes starts to reflect that, too.
What is SAP, and why does it matter for EPCs?
The Standard Assessment Procedure (SAP) is the UK Government’s approved methodology for assessing the energy performance of homes. It is used to produce EPCs, which provide an assessment of a property’s energy efficiency.
However, the current methodology has significant limitations.
EPC ratings are currently based on estimated energy running costs, calculated using standardised energy prices that don’t reflect the range of electricity tariffs available to households today.
This is particularly important for technologies like the ZEB, which uses intelligent controls to charge when electricity is cheaper, storing energy as heat to use when it’s needed.
By failing to account for modern smart tariffs and the benefits for flexible energy use, the current methodology doesn’t accurately reflect how heat batteries operate or the savings they can offer homeowners.
It’s a clear example of why EPC assessments need to evolve to keep pace with advances in home heating technology, and why we’ve been working to ensure heat batteries are properly recognised.
How EPCs are changing
The Government plans to replace SAP with the Home Energy Model (HEM), introducing a more detailed approach and accurate modelling of energy consumption and modern energy tariffs.
Alongside this, proposed EPC reforms will introduce a wider range of metrics, including fabric performance, heating system, smart readiness and energy costs.
These changes will provide a much more complete picture of a home’s energy performance, including the benefits of low-carbon heating technologies that can use electricity more flexibly.
The full benefits of these reforms will become clearer as the new methodology and EPC framework are introduced, however, it’s another positive step towards an assessment system that better reflects the technologies available to homeowners today.
What does this mean for ZEB owners?
With the ZEB now included in SAP Appendix Q, EPC assessors can model it as part of their assessment.
This could mean an improved EPC rating for homes with a ZEB installed, although under the current methodology, we expect the improvement to be relatively modest.
Further benefits will come when HEM is introduced, with its more accurate representation of heating systems, energy consumption and tariffs.
Nevertheless, inclusion in Appendix Q is an important step forward. It’s formal recognition that today’s heat batteries offer something very different from traditional direct electric boilers, electric dry core storage boilers and electric storage heating..
By combining advanced thermal storage with intelligent controls, the ZEB provides a cheaper, more flexible way to heat homes without burning fossil fuels.
And as we work towards a future of low-carbon heating, it’s important that the systems used to assess our homes keep pace with innovation.
Getting your ZEB recognised on your EPC
If you’re arranging an EPC assessment for a property with a tepeo ZEB, it’s worth making sure your assessor knows about this update.
Ask them to include it as a tepeo Zero Emission Boiler (ZEB) in the assessment, using the spreadsheet provided on the Appendix Q website.
This will help ensure your ZEB is properly recognised in your property’s EPC, reflecting the contribution it makes to improving your home’s energy performance.
A positive step towards smarter home heating
Getting the ZEB recognised in SAP Appendix Q has taken several years of work, and we’re delighted to see this progress.
There’s still more to do to ensure EPCs fully reflect the benefits of flexible, low-carbon heating, but this is an important step in the right direction. Because as home heating evolves, the way we measure it needs to evolve too.
