A home battery does not automatically improve your EPC score

An energy bill and an EPC answer other questions

You can see less grid import in an app and expect your home to get a better label. That is an understandable thought, but the residential EPC works with a calculated building performance. It's not a reckoning of your personal electricity consumption over the past month.

With a home battery, the distinction is extra important: the official EPC explanation confirms that the battery does not improve the score. A calculation of possible billing benefits should therefore not be proposed as a prediction of your next energy label. In the case of a combined offer, ask explicitly what advantage is involved in which system.

Sources: Flanders explanation at the EPC Residential

Put your first goal at the top of the conversation

Do you want to fill in a renovation obligation, use more own solar power or examine a particular emergency power function? Write down one main goal and put any additional wishes underneath. For an unclear purpose, two well-meaning proposals can hardly be comparable.

Suppose you have a budget available for another renovation phase. Have an energy expert assess the label-oriented package and ask for a battery proposal separately. Then compare not only purchase prices, but also whatever problem each package really solves. A product doesn't have to be useless because it doesn't contribute to your first goal.

Examine the battery with real usage moments

Flanders describes a home battery as temporary storage and stresses that capacity should connect to the usage profile. There is no standard format suitable for every home. A large storage capacity in itself is therefore not proof of an appropriate investment.

For your conversation, gather not only an annual total, but also information about withdrawal and injection at different times. Indicate what changes soon, like an electric car or another heater. Let the proposal clearly distinguish what is measured, what is estimated and what future choice is not yet established.

Sources: Flanders home battery: operation and dimensioning

Ask for two separate conclusions

A clear renovation report can indicate what measures are still being examined for the label. A clear battery proposal can explain why a certain capacity and control fits your consumption. Those conclusions need not be drawn by the same party.

Ask to make savings assumptions visible: what rate, what usage and what costs are included? If a proposal mentions backup power, let it describe which consumers are actually supported and what additional implementation is needed. Do not use such functions as loose ticks without knowing what they mean in your home.

Let your quote match your real priority

Tell Wattra immediately when your question arises from an EPC or a renovation obligation. Then we can delineate the technical conversation and avoid that a battery proposal seems unintentionally a solution to a label problem. For the EPC assessment you need your energy expert.

For battery storage in Flanders we look at the existing installation, your plans and the desired operation. You don't get guaranteed EPC gain or fixed payback period based on just the number of solar panels. The most useful next step is a concrete profile, a picture of the setup and a clear description of your goal.