Klimabonus 2026: the solar subsidy scale in Luxembourg
The Klimabonus, in force since 4 January 2026, finances up to €10,000 for a residential solar installation and up to €2,250 more for a storage battery.The exact amount depends on the installed power, following an official degressive formula. Find the detailed scale and the regulatory source below.
Grant scale by power (kWp)
Official formula: Grant = Ppv × (1.155 − 1.155 / 35 × Ppv), where Ppv is the peak power in kWp. The grant is capped at €10,000 for any installation of 15 kWp or more.
| Installed power | Estimated Klimabonus grant |
|---|---|
| 3 kWp | €3,168 |
| 4 kWp | €4,092 |
| 5 kWp | €4,950 |
| 6 kWp | €5,742 |
| 7 kWp | €6,468 |
| 8 kWp | €7,128 |
| 9 kWp | €7,722 |
| 10 kWp | €8,250 |
| 15 kWp and above | €10,000 (cap) |
Source: Guichet.lu — Klimabonus 2026, grant for technical installations. Minimum eligible power: 2 kWp. These amounts are indicative, calculated from the official formula — the final amount depends on the application as approved by the administration.
Grant scale for a storage battery
Official formula: Grant = Qbat × (500 − 500 / 18 × Qbat), where Qbat is the capacity in kWh. Cap of €2,250 reached from 9 kWh; minimum capacity required: 2 kWh. To see whether a battery makes sense for you, read ourbattery storage guide.
| Battery capacity | Estimated Klimabonus grant |
|---|---|
| 2 kWh | €889 |
| 4 kWh | €1,556 |
| 5 kWh | €1,806 |
| 6 kWh | €2,000 |
| 7 kWh | €2,139 |
| 8 kWh | €2,222 |
| 9 kWh and above | €2,250 (cap) |
Who is eligible?
The scheme targets owners of an existing residential building. The solar installation must have a minimum power of 2 kWp, or 1.5 kWp per unit in a multi-unit building. Invoices must be dated between 4 January 2026 and 31 December 2029 (extendable to 31 December 2031 if ordered before end of 2029).
Reduced 3% VAT rate
In addition to the Klimabonus, eligible residential photovoltaic installations benefit from a reduced VAT rate of 3% instead of the standard 17%, further lowering the balance to finance after the grant is deducted.
How do you apply?
The application is filed on Guichet.lu, within 4 years of 31 December of the invoice year (final deadline: 31 December 2031). A detailed quote from the installer is required to document the application. Pre-financing: since 4 January 2026, an installer on the register of approved installers can deduct the grant directly from the photovoltaic invoice — you only pay the net balance, without advancing the subsidy. For invoices issued from 1 January 2027, this pre-financing is integrated into Klimabonus 2026 (register of intermediary applicants), provided the deposit paid does not exceed 30% of the final price. A battery added later to an existing installation stays in the standard procedure.
Our partner installer is familiar with the Klimabonus process in Luxembourg.
Additional municipal subsidies
Several Luxembourg municipalities offer additional grants, combinable with the Klimabonus. These local schemes vary by municipality. See also our page onsolar panel prices in Luxembourg to estimate your remaining cost after the grant.
Frequently asked questions about Klimabonus and solar power
What is the Klimabonus?
The Klimabonus is Luxembourg's state financial support scheme for energy renovation measures and renewable energy installations, including solar panels. The 2026 scheme, in force since 4 January 2026, is managed via Guichet.lu and myenergy, the national energy information agency.
What exactly is the grant amount for solar panels?
The grant follows the official formula Grant = Ppv × (1.155 − 1.155/35 × Ppv), where Ppv is the peak power in kWp, capped at €10,000 from 15 kWp. In practice: about €4,950 for 5 kWp, €7,128 for 8 kWp and €8,250 for 10 kWp. See the full scale above.
Is the storage battery subsidised separately?
Yes. The formula is Grant = QBat × (500 − 500/18 × QBat), where QBat is the capacity in kWh, capped at €2,250 from 9 kWh. The minimum capacity required is 2 kWh, and the minimum solar power is 1.5 kWp per unit in a multi-unit building.
What are the eligibility conditions?
The solar installation must have a minimum power of 2 kWp. Invoices must be dated between 4 January 2026 and 31 December 2029 (extendable to 31 December 2031 if ordered before end of 2029). The application must be submitted within 4 years of 31 December of the invoice year.
Is the Klimabonus paid before or after the work?
Both are possible. Since 4 January 2026, pre-financing already exists for photovoltaics (with or without a battery): if your installer is on the register of approved installers, the grant is deducted directly from the invoice, so you only pay the net balance. For invoices issued from 1 January 2027, this scheme is integrated into Klimabonus 2026 via the register of intermediary applicants. Outside this framework, the application is filed on Guichet.lu and payment follows completion of the work. In all cases, a deposit exceeding 30% of the final price makes the installation ineligible for pre-financing.
Can the Klimabonus be combined with municipal subsidies?
Yes, in several Luxembourg municipalities. These local schemes vary by municipality — see our municipality pages (currently available in French) for details relevant to your area.
Do you need a certified installer to receive the grant?
Yes: the installation must be carried out by a professional meeting the scheme's technical criteria, and to benefit from pre-financing the installer must be registered as an intermediary applicant. Confirm this with your installer before signing a quote.
Does the reduced VAT rate apply to solar panels?
Eligible residential photovoltaic installations benefit from a reduced VAT rate of 3% instead of 17%, further lowering the amount to finance on top of the direct grant.