The right support for your solar project.

Klimabonus Wunnen supports eligible home energy improvements in Luxembourg. It covers energy renovation and selected renewable energy technologies. Start with the measure you are planning, then check its requirements: the conditions for solar panels, heating and insulation are different. [S15]

Owners of qualifying residential property can apply under the relevant procedure. Certain groups and legal entities can also qualify. Identify the applicant, property use and ownership arrangements at the outset; eligibility for a grant does not automatically mean eligibility for pre-financing. [S9, S3]

The main technical and renovation grants are assessed under the conditions for the investment. The separate Topup Klimabonus has household income and composition criteria. Treat the basic grant and any social supplement as two separate checks when preparing your budget. [S15, S6]

Some technical measures cover new and existing homes, with different rates. Energy renovation support concerns residential buildings more than ten years old, measured from the building permit. Establish your building category before comparing offers. [S2]

Renting out a residential property does not by itself settle the grant question. Check the owner’s status and the conditions of the chosen measure. Topup has additional main-residence requirements, so a landlord should not assume that social support applies to a rental investment. [S8, S6]

Agree who is authorised to act for the owners before ordering a shared installation. Ask the administrator to coordinate the decision, cost allocation and application. A commonhold decision or mandate may be needed; the current solar pre-financing procedure expressly provides for representation of co-owners. [S3]

The published maximum photovoltaic grant is €10,000. Below the threshold specified in the official schedule, support is calculated from installed peak power rather than one fixed percentage of your quotation. A larger advertised maximum is not necessarily the amount for your home. [S4, S5]

Using P × (1,155 − 33 × P), the calculated examples below 15 kWp are €4,950 for 5 kWp, €7,128 for 8 kWp and €8,250 for 10 kWp. The official Guichet schedule places systems from 15 kWp in the €10,000 maximum band. Confirm the applicable threshold treatment for your application. These figures assume eligibility. [S1, S4]

The published scheme requires at least 2 kWp and self-consumption. Eligible locations include roofs, façades, building-integrated installations and qualifying associated structures such as carports. Check the exact arrangement before ordering, especially if you are planning an unusual mounting location. [S5]

Yes, eligible self-consumption installations can sell surplus generation at market rates. The new investment grant requires giving up the regulated guaranteed feed-in tariff. Compare the complete financial arrangements before committing to either route. [S4, S10]

A market-rate export contract pays according to the supplier’s agreed commercial terms. A guaranteed feed-in tariff follows a regulated remuneration arrangement. The new Klimabonus solar investment grant requires renouncing the guaranteed tariff; this is a binding choice, not simply a setting you change in the monitoring app. [S4]

The maximum published battery grant is €2,250. For eligible usable capacity below 9 kWh, the calculation is Q × (500 − 500/18 × Q). A 5 kWh example gives approximately €1,805.56; at 9 kWh the result is €2,250. Use usable capacity, not a different headline capacity from the sales brochure. [S11]

Yes, a qualifying battery can be added to an existing identifiable self-consumption PV system. It follows the standard reimbursement procedure rather than solar pre-financing. Check compatibility, previous support and the applicable battery conditions before buying. [S1, S9]

Further support is subject to repeat-installation rules. The current solar pre-financing guidance specifies a two-year interval for certain additional PV installations and five years for an additional battery. Bring the previous commissioning, purchase and grant documents to the project review. [S3, S11]

For an existing single-family home replacing fossil-fuel or direct electric heating, the published base amount is €10,000. The enhanced amount is €12,000 when the qualifying order and invoice dates are met. New homes, apartment buildings and projects without that replacement have different rates. [S12]

For a single-family home replacing fossil-fuel or direct electric heating, the published base grant is €12,000, increasing to €14,000 in the qualifying enhanced period. Budget drilling, permits and associated works separately when assessing the remaining investment. Other configurations have different amounts. [S12]

Yes. Replacing fossil-fuel or direct electric heating is relevant to the higher replacement rates. Record the existing equipment and include the replacement scope in the quotation. Do not use a replacement example to estimate support for a new building. [S12]

The published enhanced window requires an order between 1 January 2026 and 30 June 2027 inclusive, with an invoice issued by 31 December 2028. Keep the dated order. A quotation alone should not be treated as proof that every condition is met. [S12]

Eligible oil tank removal can receive €1,500. Adaptation of existing heat distribution can receive up to €2,000 for a single-family home, capped at 50% of actual costs. Check the qualifying replacement conditions and ask for these items to be documented separately. [S1]

The programme includes selected solar thermal, biomass and heating-network measures. Their rules differ from heat pump rules. Some fossil-fuel hybrid systems and other technologies are excluded from the 2026 support framework. Check the selected technology rather than assuming every renewable-labelled product qualifies. [S7]

Eligible measures include insulation of roofs, walls and certain floors or ceilings, window replacement and controlled ventilation. Ordinary decoration or a general roof repair is not equivalent to a qualifying energy measure. Describe each improvement precisely in the assessment and quotation. [S8]

There is no single insulation grant for every house. Relevant inputs include the element, eligible surface, material and performance level. Ask for a calculation showing the measured area and applicable category. Temporary enhanced renovation rates depend on the approval-in-principle application window. [S8, S7]

Qualifying windows and French windows can receive renovation support. Glazing performance and the building’s wall or ventilation conditions matter. Ask the adviser to check the whole requirement before ordering; choosing triple glazing alone does not establish eligibility. [S8]

Eligible controlled ventilation can receive support, subject to system performance and building requirements. Review ventilation together with airtightness and insulation. This helps avoid treating a ventilation unit as a standalone purchase when the grant assessment also concerns the building. [S8]

Renovation aid applies to qualifying residential buildings older than ten years from the permit date. Material type, insulation thickness and thermal performance can affect eligibility and rates. Ask for the proposed material and performance values to appear in the technical documents. [S8]

An energy consultation is mandatory when renovating more than one envelope element under this procedure. For a single-family home, the published consultation aid is €1,700, temporarily €2,000 when the qualifying approval application is submitted by 30 June 2027. Conditions and supporting documents apply. [S2]

A simplified route exists for one qualifying envelope element without a full energy consultation. A wider renovation requires the consultation route. Decide the intended scope early: dividing invoices does not by itself make a multi-element project eligible for the simplified procedure. [S2, S9]

Subtract only the aid applicable to your project from the complete installation price. For example, a hypothetical €20,000 quotation for eligible 8 kWp PV and a 5 kWh usable battery gives calculated state aid of about €8,933.56 and a remaining cost of €11,066.44. This is an illustration, not a Voltmax quotation or grant award. [S4, S11]

For an eligible project, a registered intermediary deducts the state aid from the final invoice and applies on your behalf. Agree the route and paperwork before committing to the purchase. Pre-financing changes the payment process; it is not another grant added to the same investment. [S3]

With standard reimbursement, you finance the invoice and receive the grant after approval. With eligible pre-financing, the grant is deducted from the final invoice through the intermediary. Compare the actual payment schedule, including deposits and costs not covered by aid, before choosing your route. [S3]

Solar pre-financing already exists for eligible new PV with or without a battery. From 1 January 2027, the published framework extends the mechanism to qualifying heat pumps and renovation works, subject to invoice dates and scheme conditions. A battery added alone to existing PV is outside solar pre-financing. [S5, S7]

Check that the intermediary is registered and that your deposit arrangement complies before paying. For solar pre-financing, deposits above the published 30% limit can rule out that route. Confirm the applicable price basis in the current procedure; do not assume this restriction automatically removes every reimbursement option. [S3]

Do not assume every quotation item is subsidised. Ask for separate lines for equipment, installation, associated works and VAT. The solar supply-and-installation VAT treatment is distinct from housing-renovation VAT, and the solar-panel reduced rate does not automatically extend to a battery. Obtain the applicable treatment for each component. [S13]

Use the investment remaining after confirmed support, realistic annual savings and ongoing costs. Include export income where relevant, finance charges and likely equipment replacement. Separate a grant calculation from an energy forecast: a larger grant does not by itself make an oversized system the better investment.

Some communes offer additional support. Check the local scheme for the property’s address, its deadline and combination limits before including it in your budget. Keep the national and municipal amounts on separate lines so you can see which decisions are still outstanding. [S5]

Use the Klima-Agence subsidy simulator, then verify the relevant commune’s current procedure. Ask whether an application or other action is needed before ordering. Save the scheme reference used for your estimate, especially if the project will be completed in another calendar year. [S5]

Topup is a separate supplement linked to an awarded Klimabonus grant. Income, household composition, ownership and main-residence conditions apply. The dwelling must have been used as housing for at least ten years; the applicant must submit a separate request within two years of obtaining Klimabonus. Do not automatically add Topup to a solar estimate. [S6]

The published range is 10% to 100% of the Klimabonus amount, subject to conditions and actual-cost limits. This is not 100% of the whole renovation bill. A cumulative capital-aid ceiling of €35,000 per beneficiary can also matter. Other qualifying capital grants can use part of that allowance. [S6]

The Klima-Agence simulator identifies supplier schemes and the nova naturstroum fund alongside state and communal support. Review each programme separately. Before accepting an offer, ask who applies, when they must apply and whether accepting it affects another source of support. [S5]

A loan finances costs that remain payable and must be repaid. Separate interest support may reduce borrowing costs for qualifying households, while VAT arrangements follow their own rules. Ask the bank and relevant authority to assess those options independently from the Klimabonus grant. [S14, S13]

Start with your property, planned work and project dates. Bring existing quotations and any earlier orders or invoices. Use the relevant official procedure to build a checklist before making further commitments. Free, independent Klima-Agence advice can help you understand the available routes. [S5]

Check the correct grant regime, any required prior procedure, permits and proposed payment route. For renovation, submit the required approval-in-principle application before work. Ask the professional to identify the exact start conditions; the later payment application is a different step. [S8, S9]

Prepare an organised project file: dated orders and quotations, itemised invoices, payment evidence, bank details and the relevant technical certificates. Depending on the measure, the authority may also need approval documents, an assessment or an ownership mandate. Use the current official form’s checklist for the exact requirements. [S9]

Use the application channel specified in the official procedure. Standard Klimabonus applications can be submitted through MyGuichet.lu or the stated paper route. For pre-financing, the registered intermediary applies on the beneficiary’s behalf. Agree any mandate and division of responsibilities before submission. [S9, S3]

The competent public authority decides the award under the relevant scheme. Voltmax can explain a project and its technical documentation; Klima-Agence provides independent guidance. A contractor’s estimate or simulator result is not an official funding decision. [S9, S5]

Voltmax can discuss your installation, explain relevant support and help prepare technical information within the agreed scope. Confirm who obtains each document, signs the mandate, submits the application and follows up requests. Keep copies and check that your household and ownership information is accurate.

For new-regime PV and batteries, the published final application date is 31 December 2031. The invoice window normally ends in 2029, extending to 2031 where the order was placed by the end of 2029 and conditions are met. Renovation has separate deadlines: the first approval application by 31 December 2030 and eligible invoices through 2035. Check the invoice-year filing limit too. [S1, S2]

Check the signed order and final invoice dates before using today’s headline amounts. Transitional PV rules can preserve an earlier option for qualifying orders, with a 31 December 2026 final-invoice deadline under the old route. Have the alternatives checked before requesting a change of scheme or submitting an application. [S10]

From 1 January 2027, eligible heat pumps, insulation, replacement windows and controlled mechanical ventilation will qualify for Klimabonus pre-financing.

This means a participating contractor can deduct the grant directly from your invoice and recover that amount from the State. You pay the remaining balance instead of paying the full invoice and waiting for the grant to be reimbursed.

There is no reliable universal payment date to promise for every application. Ask the responsible service about your complete file and respond promptly to requests. Build a cash-flow plan that can tolerate a delay; a planned grant should not be treated as money already in your bank account.

Common practical risks include using the wrong procedure, missing a deadline or submitting incomplete evidence. Review any request from the authority against your original application, then supply the requested documents through the stated channel. If a decision is negative, check the reasons and the review or appeal instructions included with it.

Notify the responsible service before assuming a pending grant follows the buyer or remains with the seller. The published ownership-change rules allow the former investor to receive aid in certain circumstances where the new owner waives it. Topup also has continuing main-residence requirements, so obtain advice before a sale. [S9, S6]