A heat pump’s running cost is a household calculation, not a single European price. Electricity tariffs, the home’s heating requirement and the installed system’s performance all affect the result. Before accepting a savings claim, homeowners should ask which inputs were used and what the estimate includes. A transparent calculation can still contain uncertainty; its value is that the uncertainty is visible and can be tested before purchase.
Separate Annual Energy From Equipment Capacity
The rated output of a heat pump describes a rate of heat delivery. It does not state how much heat a home will need across a year. Keep the annual demand estimate separate from the unit selection, and identify whether that estimate covers space heating alone or domestic hot water as well. Otherwise, two cost forecasts may appear comparable while paying for different services.
Request the basis for the annual demand figure. It may use a building assessment and supporting household records, but the assumptions about occupancy and indoor temperature should be explicit. If insulation improvements are planned, ask for a calculation reflecting their timing. An estimate for the renovated house should not be presented as the expected bill before that renovation is finished.
Understand the Performance Number
The European Commission’s space-heater information distinguishes energy information for different applications and climate conditions. When reviewing a product label or fiche, check that it belongs to the exact model and the heating arrangement being proposed. A favourable rating at one water temperature should not be silently substituted for performance at another.
The Thermalux R290 inverter heat pump product page publishes performance rows at different test conditions. These provide material for a technical comparison, but a test-point coefficient of performance is not an annual household result. Ask the installer to explain the seasonal assumption used in the estimate and whether it includes supplementary electric heating and circulation equipment.
Use an Explicit Worked Example
Suppose, purely for illustration, that a home needs 12,000 kWh of useful space heat during a year. If the assumed seasonal performance factor is 3.0, with all electricity for that space-heating system included, the estimated consumption is 4,000 kWh. At an assumed flat electricity price of EUR 0.25 per kWh, that part of the annual cost would be EUR 1,000. These inputs are examples, not a European average or a product performance claim.
That calculation excludes domestic hot water, household appliances, standing charges and maintenance. It also assumes a flat tariff. For an actual quotation, replace each illustrative input with the household’s agreed assumption. If supplementary consumption is excluded from the chosen performance factor, account for it separately and label it clearly. Do not add the same electricity twice under different headings.
Test the Forecast Against Less Favourable Conditions
Ask for a second calculation using a lower seasonal performance assumption and a higher electricity price. The purpose is to see whether the household can tolerate a less favourable outcome, not to predict the worst possible winter. Keep the heating demand consistent when comparing alternative systems, unless a documented building change explains the difference.
If a time-of-use tariff is proposed, request an estimate of when electricity would be consumed rather than multiplying everything by the cheapest advertised rate. Energy Saving Trust discusses heating curves and tariff choices as factors in efficient operation. Applying those ideas to a particular home still requires a suitable control strategy and realistic assumptions about the household’s routine.
Include the Costs Outside the Meter
Installation work, servicing and any financing costs belong in a broader ownership comparison. Keep them separate from the electricity calculation so the reader can see what drives each figure. If financial support is relevant, verify current eligibility for the specific country and project before subtracting it from the investment. Do not assume that a scheme elsewhere in Europe is available locally.
Devotion offers a route to manufacturer information; the local proposal should turn that information into an estimate for the actual home. Ask who will review performance after installation and what records will be available. A useful forecast becomes a reference for that review: the household can compare measured electricity, weather and comfort against the original assumptions, rather than judge the system against an unexplained percentage saving.