Personalised solar estimate

The solar estimate offered on this page produces an indicative calculation example based on the information you enter. It is not a commercial offer, not a quote, and not a guarantee of actual production: it is a starting point for judging whether a project is worth pursuing before you approach installers.

The result shown depends entirely on the quality of the data entered. Two neighbouring households that enter different consumption figures or roof orientations will get different results, not because the tool is wrong but because it simply applies the assumptions provided. Always treat the figure obtained as a calculation example to be verified, never as a guaranteed outcome.

Annual consumption in kilowatt-hours, taken from your energy bill, is the most decisive input: it sets the order of magnitude of capacity that makes sense for your home, independently of the roof surface available.

Roof orientation and pitch directly affect the estimated production: a south-facing roof with a moderate pitch is usually most favourable, but east- or west-facing roofs remain relevant if they better match your consumption pattern during the day. Shading from a tree, a chimney or a neighbouring building can noticeably reduce actual production without the online estimate being able to detect it.

The roof surface actually available, once obstacles and safety clearances are deducted, and the share of your consumption that occurs during daytime hours complete the parameters that should be entered as precisely as possible.

No online tool can measure actual shading, check the condition of the roof structure and covering, or verify whether the existing electrical panel can accommodate a photovoltaic installation. These points can only be assessed on site, and they can significantly change the recommended capacity compared with the online estimate.

Never treat an online estimate as sufficient grounds for ordering equipment or signing a contract. It is meant to frame your request before contacting installers, who will confirm or adjust the sizing after visiting the property.

Residential solar power in Luxembourg is supported by the Klimabonus Wunnen, which replaced the former PRIMe House programme in 2022. This national housing support scheme applies according to a scale set per bracket of installed capacity, with a separate component for any battery added.

No figure is stated here, since the official scale can change and must be checked directly on guichet.lu at the time of your project. A reliable installer will confirm in writing how the subsidy relates to the quote it submits to you.

Once you have an estimate and have contacted one or more companies, ask them to confirm in writing: the capacity in kilowatt-peak actually retained after the site visit, the expected annual production and the assumptions behind it, the estimated share of self-consumption, and the warranties covering the panels and the inverter.

These written details are what allow you to compare several quotes reliably, far more than the result obtained at the online estimate stage.