2026 solar grants in Luxembourg at a glance

For a house, three grants add up in 2026: the Klimabonus for the panels, the one for the battery and, for invoices issued from 1 October 2026, the one for the energy management system. The guaranteed feed-in tariff rules them out: it is one or the other.

Your commune almost always adds a grant: 93 of the 100 communes pay €250 to €2,871 for 6 kWp (see municipal solar PV grants); its own regulation applies, so check before you sign. Klima-Agence gives free advice on 8002 11 90.

Solar Klimabonus 2026: the amount by installed output

The solar Klimabonus is calculated with the official formula P × (1,155 − 33 × P) (guichet.lu), where P is the peak output in kWp, for a system below 15 kWp; from 15 kWp, the grant is a flat €10,000. The grant per kWp therefore falls with size: it rewards systems sized to the household’s consumption.

Amounts checked on 28 September 2026: official formula P × (1,155 − 1,155/35 × P) euros, i.e. P × (1,155 − 33 × P) euros, for an output P from 2 to less than 15 kWp; flat €10,000 from 15 kWp. Amounts rounded to the euro.

Legal basis: in 2026 the solar grant and the battery grant fall under the law of 19 December 2025 introducing a pre-financing procedure (parliamentary doc. 8463, Ministry of the Economy), for invoices issued from 4 January 2026. From 1 January 2027 they are taken over by the Klimabonus Wunnen law of 24 July 2026, whose articles 10, 11, 16 and 17 enter into force on that date, with the same formulas. Standard applications are handled by the Environment Agency (Administration de l’environnement).

The battery storage grant in 2026

A battery connected to a self-consumption solar system receives Q × (500 − 500/18 × Q) euros, where Q is the usable capacity in kWh, below 9 kWh, and a flat €2,250 from 9 kWh. Amounts checked on 28 September 2026, same legal basis as the panels; details and examples are on our home battery grant page.

• A new battery is only funded 5 years after the purchase of the previous one.
• In an apartment building, the PV system must exceed 1.5 kWp per dwelling.
• Pre-financing: possible for a battery bought together with the panels, not for a battery added on its own to an existing system (standard procedure).

Prices and choice of capacity: see our guide to home battery storage.

2026 feed-in tariff: the alternative to the Klimabonus

The guaranteed feed-in tariff still exists: for a system first feeding into the grid in 2026, it pays €0.1333/kWh up to 10 kWp and €0.1252/kWh from 10 to 30 kWp for the electricity fed in, for 15 years from the first injection, without indexation (Klima-Agence). Choosing it means giving up the 2026 Klimabonus: the choice is made before commissioning and cannot be reversed.

• Annual reduction: the tariff falls by 3% a year depending on the year of first injection (amended Grand-Ducal regulation of 1 August 2014). The €0.1374/kWh figure still shown on some websites is the previous year’s value.
• Self-consumption remains possible: the guaranteed tariff only pays for electricity fed into the grid; this requires a separate production meter.
• Without the guaranteed tariff, the surplus is sold at market price: suppliers offer variable buy-back contracts linked to the market value of solar electricity (for example 90% of the index at Sudstroum for customers who also buy their electricity there).

Which pays more? For systems of 3 to 6 kWp, the Klimabonus pays at least as much; from about ten kWp with little self-consumption, the guaranteed tariff is often more attractive. The detailed calculation is on our page on payback: Klimabonus or feed-in tariff.

Applying for the solar grant, step by step

The solar grant needs no prior approval: unlike insulation, the application is made after installation, either by the installer (pre-financing) or by you (standard procedure). The amount is the same either way.

Route 1: pre-financing, the installer applies

1. Choose a registered installer listed in the register of installers admitted to pre-financing, published by the Ministry of the Economy on guichet.lu.
2. Sign the offer and the mandate: you co-sign with the installer the statement authorising them to apply for the grant on your behalf. The deposit may not exceed 30% of the price including VAT.
3. Installation and declarations: the installer registers the system with the grid operator (Creos via myCreos in most municipalities), then submits the end-of-works declaration required for the grant.
4. Final invoice: it states the output, the battery capacity if any, the grant deducted and the deposits paid.
5. Decision: the administration decides within 15 working days (no reply means the application is approved) and pays the installer within the next 15 working days. You pay the balance.

Route 2: the standard procedure, you apply yourself

1. After installation, gather the itemised invoice, proof of the end-of-works declaration to the grid operator and your waiver of the feed-in tariff.
2. Submit form DEPA-2026 with the solar PV sheet (PHOT-2026) on MyGuichet.lu, or on paper to the Guichet unique des aides au logement (11, rue de Hollerich, Luxembourg, tel. 80 02 10 10).
3. Meet the dates: invoices issued from 4 January 2026 to 31 December 2029 (until 31 December 2031 if the order was signed by 31 December 2029), application by 31 December 2031 at the latest.

Pre-financing, VAT and loan: what you need to know in brief

• Pre-financing: optional, same grant amount; excluded for a leased system and for a battery added on its own, and reserved for private individuals and non-commercial legal entities. Details on our page on solar pre-financing and financing.
• VAT: 3% charged directly on supply with installation, without approval; the effect on a quote is worked out on our page on solar panel costs.
• Klimaprêt: the State pays 1.5% of interest a year on a bank loan, with no income condition, once the Klimabonus has been granted. The zero-interest loan no longer exists for new applications.

Order signed by 4 March 2026: the old scheme’s options

If your order was signed by 4 March 2026, you can still choose an option from the old scheme, provided the invoice is issued by 31 December 2026. These options then disappear.

For 6 kWp ordered in February 2026, the 50% option pays more than the 2026 flat amount of €5,742 as soon as eligible costs exceed €11,484: ask your installer to calculate both options.

Examples: how much does a house receive in 2026?

With the reference prices from our page on the cost of a solar PV system (renov.lu survey, September 2026, 3% VAT included), the net cost is as follows:

With pre-financing, these grants are deducted from the invoice incl. VAT and the deposit is capped at 30% of the price. The Klimabonus for panels can also be combined with grants for a heat pump and for insulation and energy renovation.

Move on to a quote with the grant deducted

Ask for quotes from installers listed in the pre-financing register: each offer must state the output, the Klimabonus deducted and the deposit requested (30% at most).

Frequently asked questions about solar grants in Luxembourg