EPCs are misunderstood, not misleading

However, it is inevitable that there will be instances where news may not be entirely fair or accurate. One recent case was when The Times newspaper reported that “EPCs were misleading”. We disagree and wrote to the paper outlining why EPCs are vital and that the article itself is not quite accurate. Equally as important we reached out to the authors of the research the article appeared to be based on.

Energy, climate change and fuel prices are never far from the current headlines and it is great to see positive news stories surrounding the importance of energy efficiency in the built environment.

The article highlighted the potential inaccuracies of domestic EPCs, citing new research conducted by Carbon Laces, an innovative startup that is helping to build financial tools for energy decarbonisation and regeneration of finance.

As always, Elmhurst welcomes all involvement and scrutiny of EPCs and the energy efficiency industry, which is why we met with Carbon Laces to discuss. Both parties agree that the headline was misleading.

EPCs have a purpose and a place - and are a modelled asset cost profile of a property, while smart meters cover actual energy use. EPCs have grown to cover actual building performance for various applications, like regulatory compliance to lending. Currently, these two outputs are fundamentally different, and comparing them is like comparing apples with pears. That is also what the research highlights.

It is vital to understand that an energy assessment and the EPC are based on standard occupancy e.g. an average family living in the property operating the home on set temperatures and running times. The EPC predicts the heating, hot water and lighting for the home based on average use patterns and average weather conditions.

They continue to serve their original purpose by enabling homebuyers or renters to compare the energy efficiency of properties and make informed decisions prior to renting or purchasing a home.

One of the key findings within the study is that occupants of properties with EPC ratings of F and G consume less energy than the standardised occupancy expects. This highlights the importance of accurately measuring and understanding occupant behaviour.

As fuel costs continue to rise, many people are likely to have significantly changed their energy consumption habits at home. However, the most inefficient homes, which are also the most expensive to run, require additional information to fully understand the outcomes observed in this context.

Were the occupants reducing their heating usage, adjusting the timing of heating schedules, or using alternative heat sources that are not metered? It is important to note that metered data also includes non-regulated energy such as cooking appliances, which the EPC does not account for.

Interestingly, homes rated EPC A and B, which are more energy efficient, appear to have higher energy consumption than predicted by the EPC. This may be due to improved insulation, which makes occupants feel comfortable keeping the heating on for longer periods compared to older, less efficient homes.

Both Elmhurst and Carbon Laces agree that in order to understand and measure a home’s energy efficiency, we need to help homeowners understand their energy consumption and make good decisions. This starts with baseline EPC (the asset), overlaying this with details of the occupant’s lifestyle, refining the predictions of energy use (the occupancy), and then finally using the metered data to check progress against the goals (the meter).

All three pieces of data, i.e. the energy cost, energy use and energy consumption, are required in harmony, and using one in isolation only tells part of the story.

One key takeaway is that the large increase in fuel prices has made it challenging for individuals living in the coldest homes and with low disposable income to afford heating, resulting in reduced usage. As experts in this sector, we all continue to push for homes to be as efficient as possible, and by employing all three metrics, we can help families to understand what to do to make warmer, cheaper-to-run, lower-carbon homes.

Elmhurst and Carbon Laces will maintain an ongoing dialogue to enable research that can help us to understand how people use energy in their homes. We at Elmhurst will also defend energy assessment and its professional members, whilst equally acknowledging that we must ensure that the methodologies and outputs (EPCs) keep improving, with more up-to-date research, innovation, fuel prices, carbon factors, and more.

Against a backdrop of rising fuel poverty, environmental pressures and energy security concerns, EPCs are coming in for a lot of scrutiny and criticism.