Financial aid for renewable energy-based technical installations (Klimabonus 2026 scheme)
Last update
Important information: Continuation and partial reform of the 'Klimabonus Wunnen' financial aid scheme
You will be able to submit your application for the Klimabonus Wunnen 2026 financial aid scheme from 1 January 2026, the date on which the scheme is scheduled to take effect, with retroactive effect if the law has not been published before that date. However, because the law is still going through the legislative procedure, the processing and consideration of your application remain subject to the publication of the law in the Official Journal.
Summary:
You can apply for financial aid under the Klimabonus 2026 scheme subject to certain conditions.
The Environment Agency (Administration de l'environnement – AEV) grants subsidies for investments in projects aimed at rationalising the use of energy and promoting the use of renewable energy sources.
This is financial aid – technical installation subsidies known as 'Klimabonus' subsidies – to subsidise the investment and installation costs of the following:
- solar thermal systems;
- solar photovoltaic systems;
- heat pumps, non-fossil fuel hybrid heat pumps, or non-fossil fuel hybrid systems with a heat pump;
- wood pellet boilers, wood stoves and particulate filters;
- the implementation of a heating network and/or connection to a heating network;
- the implementation of an energy management system.
These subsidies:
- apply to:
- renovation projects;
- new construction; and
- may also be applied for independently of such projects.
For each type of system, potential applicants should contact the communal administration for the area where the building is located to ascertain whether a building permit is required.
The business that commissioned the heat pump must submit an application for approval to the Building Inspection and Approval Department (Service de contrôle et de réception du bâtiment) of the Chamber of Skilled Trades and Crafts (Chambre des métiers) within one month of the heat pump being commissioned.
Klimabonus aid is paid only once per technical installation.
Who is concerned
Financial aid may be sought by any person wishing to improve the energy performance of their home (single-family house or house divided into flats). Eligible candidates include:
- natural persons;
- legal persons established under private law;
- public legal persons other than the State.
You can submit your application in your capacity as:
- the legal representative of a group of natural or legal persons, provided that you are a part of this group yourself;
- the owner(s) of the dwelling, except when there is a change of ownership and the new owner of the dwelling and/or technical installation forgoes the aid in question for the benefit of the former owner who made the investments.
Prerequisites
Installations and residences
The Klimabonus aid:
- is granted only for residential buildings located in Luxembourg;
- is not granted for:
- used (second-hand) systems; or
- an exchange, replacement or repair of a part of a system that cannot function independently of the rest of the system.
Technical installations for which financial aid was granted under the 2022 or 2017 financial aid scheme are not eligible.
Requirements
Solar thermal systems
Solar thermal systems must meet the following requirements:
- solar thermal collectors must be certified by the European Solar Keymark quality mark;
- the system must be equipped with a calorimeter;
- the gross surface area of the collectors with complementary heating must be:
- greater than or equal to 9 m2 for flat-plane collectors;
- greater than or equal to 7 m2 for vacuum tube collectors;
Thermal solar systems are eligible for the financial aid if they are installed in existing residential buildings and if the invoice for the system is dated at least 10 years after the building permit was issued.
Non-glass thermal collectors with polyethylene pipes and hybrid solar collectors generating hot water and electricity are not eligible for the financial aid.
Solar photovoltaic systems
The pre-financing procedure is managed by the Ministry of the Economy (Ministère de l’Économie). Pre-financing is applicable for new photovoltaic systems installed with or without a storage battery. Pre-financing is not available for installing a storage battery in an existing photovoltaic system.
You may, however, apply for post-financing (the traditional procedure) by submitting an application to the Single point of contact for housing assistance (Guichet unique des aides au logement). This aid will be processed by the Environment Agency.
To receive aid to install a storage battery in an existing photovoltaic system, you must complete the post-financing procedure.
Photovoltaic systems are not eligible for pre-financing under RGD2022.
You may not submit a double application, one application for 2 aid schemes, or a combined application for pre-financing and post-financing.
Solar photovoltaic systems must meet the following requirements:
- they must be operated in self-consumption mode, and the applicant must explicitly waive the benefit of compensation for electricity injected into the electrical grid of a network operator in accordance with a legal or regulatory provision. However, the applicant may inject surplus electricity produced into the grid and resell it at market rates;
- the peak power capacity of the system must be at least 2 kW;
- the system must be:
- installed on the roof or facade of the building; or
- incorporated in the building envelope.
Hybrid solar collectors generating hot water and electricity are eligible as photovoltaic collectors.
An application for financial aid for photovoltaic systems may be submitted for:
- a standalone photovoltaic system;
- a photovoltaic system equipped with a storage system;
- a standalone storage system for an existing, identifiable photovoltaic system.
The electricity storage system must meet the following requirements:
- the storage system must be connected to a solar photovoltaic system operating in self-consumption mode;
- an additional storage system intended to be installed in a specific solar photovoltaic system is not eligible for financial aid until 5 years after the purchase of the last storage system installed in the solar photovoltaic system in question, with the invoice date constituting proof thereof;
- the storage capacity must be at least 2 kWh;
- for a multi-unit residential building, the peak power capacity of the solar photovoltaic system must be greater than 1.5 kW per private unit.
Heat pumps
Heat pumps concerned
The following heat pumps and hybrid heat pumps are concerned:
- geothermal heat pumps with vertical sensors (geothermal probes) or horizontal sensors (geothermal collecting lines and baskets) meeting the following coefficient of performance (COP) requirement: COP is equal to or greater than 4.3 at B0/W35, determined in accordance with the EN 14511 standard;
- non-fossil fuel hybrid geothermal heat pumps for existing residential buildings that:
- are installed in addition to an existing non-fossil fuel heating system to create a hybrid system, or are installed in the form of combined hybrid devices to replace an existing heating system; and
- must meet the following coefficient of performance (COP) requirement: COP is equal to or greater than 4.3 at B0/W35, determined in accordance with the EN 14511 standard;
- direct expansion geothermal heat pumps compliant with the following coefficient of performance (COP): COP is equal to or greater than 4.3 at E4/W35, determined in accordance with the EN 14511 standard;
- heat pumps combined with a latent heat accumulator and a solar thermal collector, compliant with the following coefficient of performance (COP): COP is equal to or greater than 4.3 at B0/W35, determined in accordance with the EN 14511 standard;
- air-water heat pumps (including vented air-water heat pumps) compliant with the following COP: COP is equal to or greater than 3.1 at A7/W35, determined in accordance with the EN 14511 standard;
- non-fossil fuel hybrid air-to-water heat pumps for existing residential buildings that:
- are installed in addition to an existing non-fossil fuel heating system to create a hybrid system, or are installed in the form of combined hybrid devices to replace an existing heating system; and
- must meet the following coefficient of performance (COP) requirement: COP is equal to or greater than 3.1 at A7/W35, determined in accordance with the EN 14511 standard.
Requirements to be met
The relevant heat pump must meet the following requirements:
- the heating system must be able to supply the heating circuit with a maximum starting temperature of 35°C (35W). If this is not the case, the performance coefficient of the heat pump must reach at least the required threshold at W35 with the chosen starting temperature;
- the power supply of the heat pump must be equipped with an electricity meter;
- the heat pump must be equipped with a heat meter;
- when a heat pump is installed, the heating network must undergo hydraulic balancing;
- for heat pumps and hybrid heat pumps for existing residential buildings, a buffer tank with a minimum capacity of 30 l/kW thermal must be installed, with the exception of heat pumps with speed/power modulation;
- a geothermal heat pump or non-fossil fuel hybrid air-to-water heat pump must be able to operate on its own, i.e. in monovalent mode, and the hybrid system must cover at least 70% of the useful heat demand for the year in heat pump mode;
- for air-to-water heat pumps and hybrid air-to-water heat pumps, the sound power LW ('Schallleistungspegel'; based on the EN 12102 standard) for the heat pump component installed on the building exterior must meet the following requirements:
| Rated capacity of the heat pump according to the ErP label [kW] | Maximum value of the sound power LW according to the ErP label [dB(A)] * |
|---|---|
| ≤ 5 kW | 48 dB(A) |
| > 5 and ≤ 12 kW | 51 dB(A) |
| > 12 kW | 55 dB(A) |
* For a system whose external component exceeds the maximum value shown in the table above, the value to take into account may be reduced by adding a soundproofing and noise protection system that reduces the sound emitted by the heat pump's external component. The sound-reduction value in dB(A) must be guaranteed and specified in the technical data of the soundproofing equipment.
Alternatively, if the sound power requirements LW in the above table are not met, the noise level, increased where necessary by correction terms, caused at the boundary of the nearest building site to the fixed technical equipment of the heat pump installed outside the building must not exceed 40 dB(A).
In order to demonstrate that the system complies with this requirement, a noise assessment based on a calculation of noise emissions shall be carried out for the fixed technical components of the heat pump installed outside the building. It is issued prior to the installation of the heat pump and exclusively on the basis of a calculation tool called the calculatrice des émissions sonores (noise emission calculator) made available by the Minister.
Wood-fuelled boilers
In order to be eligible:
- the system must have controlled combustion (power and combustion regulation);
- wood pellet boilers must be equipped with an automatic feeder and ignition system;
- wood pellet boilers must power a central heating circuit;
- wood pellet stoves must be integrated in a central heating system and the degree of useful heat transfer must reach at least 50 %;
- wood pellet stoves or closed household wood stoves (using only solid renewable fuels) must be installed in a single-family house that does not have central heating. Wood pellet stoves or wood stoves must meet an energy efficiency class of A+ or better (according to the ErP label);
- the following emission and yield thresholds must be complied with:
- particle emission less than or equal to 8 mg/m3;
- nitrogen oxide (NO) emission less than or equal to 200 mg/m3;
- boiler production yield greater than or equal to 90%;
- combustion yield of pellet stove greater than or equal to 90%.
For a single-family house without central heating, the yields of the pellet stoves or wood stoves may be lower than 90 %.
Wood-fuelled boilers may be equipped with a particulate filter (electrostatic or other) whose separation efficiency ('Abscheidegrad') must be such that the particle emission rate of the system after commissioning/acceptance does not exceed 8 mg/m3.
Heating networks and connections
The transfer of heat between the heating network and the residential building must occur through a heat transfer station.
Energy management systems
To be eligible for the financial aid, energy management systems (hereinafter: 'systems') must enable the connection and integration of at least 2 of the following devices:
- a heat pump, hybrid heat pump, or a hybrid system with a heat pump;
- a charging station within the meaning of Regulation (EU) 2023/1804 of the European Parliament and of the Council of 13 September 2023 on the deployment of alternative fuels infrastructure;
- an electricity storage system;
- a solar photovoltaic system;
- a controllable immersion heater that is used for heating a central reservoir of domestic hot water.
All the devices listed above that are already connected to the relevant electrical network when the system is installed must be connected to the energy management system.
Energy management systems must be installed and commissioned by:
- an installer that is based in Luxembourg and holds a business permit to operate as an electrician, heating-sanitary-refrigeration installer or electronic equipment installer;
- an installer based in a Member State that occasionally travels to Luxembourg on a temporary basis and has:
- in the Member State where it is based, a permit to install systems and, where applicable, connect them to the public electrical grid;
- a certificate of prior declaration in accordance with Article 7 of the Law of 28 October 2016 on the recognition of professional qualifications, as amended (loi modifiée du 28 octobre 2016 relative à la reconnaissance des qualifications professionnelles).
For an energy management system, the amount of financial aid is EUR 500.
Deadlines
Applications for the financial aid must be filed with the Single point of contact for housing assistance no later than 4 years after 31 December of the calendar year in which the invoice was issued.
You may apply for financial aid for the investments and services for which the invoice has been issued:
- for all technical installations, other than photovoltaic systems and storage systems, between 1 January 2026 and 31 December 2030 inclusive;
- for energy management systems, between 1 October 2026 and 31 December 2030 inclusive;
- for all technical installations, other than photovoltaic systems, until 31 December 2035 inclusive, if the investments are concurrent with the energy efficiency renovation of an existing building;
- for photovoltaic systems and storage systems, between 4 January 2026 and 31 December 2029. This deadline will be extended to 31 December 2031 provided that the systems were ordered by 31 December 2029.
You will lose your entitlement to financial aid if you submit your application more than 4 years after 31 December of the calendar year to which the invoice in question pertains.
For photovoltaic systems and storage systems, you must file your financial aid application by 31 December 2031.
If the technical installations (other than photovoltaic systems and storage systems):
- are installed concurrently with the energy efficiency renovation, the deadline for filing the application is 31 December 2039 at the latest. The invoice must be issued by 31 December 2035 at the latest;
- are installed concurrently with a new sustainable construction that is eligible under the 2017 aid scheme, the deadline for submitting the application is 31 December 2031 at the latest. The invoice must be issued by 31 December 2029 at the latest.
How to proceed
Filing an application
You must file your application after the works are completed:
- either online via MyGuichet.lu or the MyGuichet.lu mobile application (see 'Online services and forms' below). This is a procedure with authentication that requires:
- a LuxTrust product; or
- an electronic identity card (eID);
- or by post (preferably by registered mail), or by handing in the dedicated form (see 'Online services and forms') at the Single point of contact for housing assistance (Guichet unique des aides au logement):
- if you are a private individual: the DEPA-2026 aid application form for natural persons; or
- if you represent a legal person: the DEPA-2026 financial aid application form for legal persons.
Supporting documents
In addition to the financial aid application, you must also provide:
- a bank account identification document (RIB) for the account indicated in the application form;
- the detailed and receipted invoices in connection with the requested financial aid. The invoices may refer to an itemised estimate, in which case the estimate must be attached to the invoice;
- one or more specific technical data sheets, depending on the type of installation:
- photovoltaic system;
- heat network or connection to a heat network;
- solar thermal systems;
- heat pumps;
- wood-fuelled boilers;
- energy management systems;
- if applicable, the energy performance assessment related to the technical installation(s) concerned;
- if applicable, the dated order form for the photovoltaic installation;
- if applicable, the dated order form for the heat pump or wood-fuelled boiler.
Given that each application may cover different areas depending on the owner's or architect's choices, the various sheets should be accompanied by any additional documents specified on the application forms.
If the application is for a commonhold property or multi-unit residence, you must include:
- the appendix form COLL-2026 and a power of attorney for each owner PROC-2026. Alternatively, a report drawn up by the commonhold association during a general meeting authorising the renovation works;
- the list of the flats, specifying the energy reference area per flat, excluding the common areas.
The Single point of contact for housing assistance may ask you to provide any documents it deems necessary to process the file.
If the aid is granted, the beneficiary's file may be reviewed at any time.
Note: implementing technical installations may also be eligible for financial aid for an energy performance assessment and a report by an approved energy consultant. If the improvement only applies to a renewable energy-based technical installation, the subsidy will be reduced by 70%.
Table of subsidies for technical installations
Subsidies for solar thermal systems
| Technical installation | Financial aid |
| Solar thermal systems for production of domestic hot water |
|
| Solar thermal systems for the production of domestic hot water combined with auxiliary heating |
|
An additional flat-rate subsidy of EUR 1,000 may be granted if the solar thermal system is installed concurrently with a wood-fuelled boiler or a heat pump.
Subsidies for solar photovoltaic systems
- Solar photovoltaic system (in self-consumption mode or as part of an energy community)
- Storage system for solar photovoltaic systems
Financial aid using a formula if the installed capacity is lower than 15 kW (EUR 10,000 maximum above 15 kW)
PPV * (1.155 - 1.155/35 * PPV) EUR
where:
Ppv is peak power capacity of the solar photovoltaic system in question expressed in kilowatts and rounded to 2 decimal places.
Financial aid using a formula if the installed capacity is lower than 9 kW (EUR 2,250 maximum above 9 kW)
QBat * (500 - 500/18 * QBat) EUR
where:
QBat is the usable capacity of the storage system in question expressed in kilowatt hours and rounded to two decimal places.
Subsidies for heat pumps
| Technical installation | Financial aid |
| Geothermal heat pump (geothermal probes, geothermal collectors or latent heat accumulator systems with solar thermal collector) |
|
| Air-to-water heat pump or compact device including the controlled mechanical ventilation system and recycled air-to-water heat pump, for new constructions |
|
| Air-to-water heat pump or compact device including the controlled mechanical ventilation system and recycled air-to-water heat pump, for existing residences |
|
| Replacement of an oil-fired boiler in a protected wetland zone | EUR 2,000 |
| Removal, neutralisation and recycling of the oil tank (if an oil-fired boiler is being replaced) | EUR 1,500 (an invoice from a specialised business in this industry is required as proof) |
| Adaptation of the existing heat distribution system |
|
Subsidies for wood-fuelled boilers (for existing residences only)
| Technical installation | Financial aid |
| Wood pellet boilers |
|
| Wood pellet stove with filter (connected to the heating network) | EUR 3,000 for a new single-family house or 50% maximum of actual costs |
| Wood pellet stove or wood stove | EUR 2,500 maximum or 50% of actual costs in a single-family house without central heating to replace a solid fuel stove more than 10 years old |
| Replacement of an oil-fired boiler in a protected wetland zone | EUR 2,000 |
| Removal, neutralisation and recycling of the oil tank (if an oil-fired boiler is being replaced) | EUR 1,500 |
Urban heating network
| Technical installation | Financial aid |
| Connection to an urban heating network |
|
| Installation of an urban heating network (at least 2 residential buildings must be connected) | EUR 20,000 or 50% maximum of actual costs |
| Replacement of an oil-fired boiler in a protected wetland zone | EUR 2,000 |
| Removal, neutralisation and recycling of the oil tank (if an oil-fired boiler is being replaced) | EUR 1,500 |
Additional aid and bonus
Wood-fuelled boilers
Aid for the installation of a particulate filter on an existing boiler may be granted. This financial aid is capped at EUR 1,500 and may not exceed 50% of the actual costs.
A 15% bonus to the financial aid may be granted if a buffer tank is installed (30 l/kWthermal rated capacity);
Other aid
Some communes grant additional aid. Applicants may estimate the amount of communal aid they are eligible for by using the Klima-Agence simulator.
Note: The Nova Naturstroum promotional bonus rewards projects that promote renewable energy sources. Further information can be found on the website enoprimes.lu.
Natural gas and electricity suppliers active in Luxembourg also offer aid programmes for the implementation of energy efficiency measures. The list of suppliers is available on the website of the Luxembourg Regulatory Institute (Institut Luxembourgeois de Régulation - ILR):
Payment of the aid
The aid is generally transferred directly to your bank account.
If you are acting in your capacity as a legal representative of a group of natural or legal persons, the aid is transferred directly to your bank account and you must immediately credit the bank accounts of the natural or legal persons concerned with their respective share of the aid.
A copy of these payments must be sent to the Single point of contact for housing assistance.
Repayment of the aid
If you have already received the aid, you may be required to return it, if:
- you are found to have made inaccurate or incomplete statements in order to obtain the aid; or
- you fail to provide the Single point of contact for housing assistance with the requested declaration, information or documents.
Online services and forms
Online services
Downloadable forms
Note: view tips for using PDF forms.
Applications and attachments (to be filled in by the applicant)
Specific forms (to be filled in by the professionals)
Certificates of conformity (to be filled in by the professionals)
Change of address and/or bank account
Who to contact
Klima-Agence
- Address:
- 2, circuit de la Foire Internationale L-1347 Luxembourg Luxembourg
- Phone:
- (+352) 8002 11 90
- Email address:
- info@klima-agence.lu
- Website:
- http://www.klima-agence.lu
Ministry of Housing and Spatial Planning Single point of contact for housing assistance
- Address:
- 11, rue de Hollerich L-1741 Luxembourg Luxembourg
- Phone:
-
(+352) 80 02 10 10
Monday to Friday from 8.00 to 16.00
- Fax:
- (+352) 45 88 44
- Email address:
- info@ml.etat.lu
- Website:
- http://www.logement.lu
Closed ⋅ Opens Monday at 8.00
- Friday:
- 8.00 to 12.00 , 13.30 to 16.00
- Saturday:
- Closed
- Sunday:
- Closed
- Monday:
- 8.00 to 12.00 , 13.30 to 16.00
- Tuesday:
- 8.00 to 12.00 , 13.30 to 16.00
- Wednesday:
- 8.00 to 12.00 , 13.30 to 16.00
- Thursday:
- Closed
Related procedures and links
Procedures
Links
Further information
-
The Solar Keymark
on the website of the European Solar Thermal Industry Federation
-
Primes
on the website of Enovos
Legal references
-
Loi modifiée du 23 décembre 2016
1. instituant un régime d'aides pour la promotion de la durabilité, de l'utilisation rationnelle de l'énergie et des énergies renouvelables dans le domaine du logement; 2. modifiant la loi modifiée du 23 décembre 2004 établissant un système d'échange de quotas d'émission de gaz à effet de serre
-
Règlement grand-ducal modifié du 7 avril 2022
déterminant les mesures d’exécution de la loi du 23 décembre 2016 instituant un régime d’aides pour la promotion de la durabilité, de l’utilisation rationnelle de l’énergie et des énergies renouvelables dans le domaine du logement
-
Projet de loi 8585
instituant un régime d’aides pour la promotion de la durabilité, de l’utilisation rationnelle de l’énergie et des énergies renouvelables dans le domaine du logement
