Installing photovoltaic panels on company roofs

Photovoltaics: an environmentally and financially interesting alternative for your company’s electricity production

A photovoltaic installation enables a business to reduce the amount of electricity it draws from the grid. This lowers energy costs and limits exposure to fluctuations in the electricity market. Beyond self-consumption, there are other support mechanisms that can represent an interesting economic model, such as the guaranteed feed-in tariff or the market premium resulting from a call for tenders. The installation can be financed from your own funds or by a third-party investor, who can also take care of its planning and completion.

Definition of the requirements

Analysis of plant location and solar potential – solar cadastre

Analysis of the photovoltaic location, taking into account its orientation, tilt angle, potential shading, available installation area, and site-specific constraints.

Verification of the expected energy production potential using the solar cadastre.

• Self-assessment of solar potential

This tool shows the annual global solar irradiation potential on your roof in kWh/m² per year.

Identify solution and check feasibility of photovoltaic panel installation project

General planning of the installation (depending on the scope of the project, in collaboration with a qualified craftsman or design office)

• Qualified craftsmen (certified electrician)
• List of large-scale photovoltaic project planners

Feasibility study of the solar panel installation project

• Technical and constructive feasibility (static calculations, roof condition, etc.): design office
• Connection feasibility: network operator. It is also important to reserve the required grid connection capacity with the grid operator, in accordance with the attached guidance note.
• Where possible, combine the installation with an energy-efficient roof renovation or insulation upgrade

Request for quotation

• Qualified craftsmen (certified electrician)
• Possibility of including plant maintenance in the offer

Subsidy application

Government subsidies

Please note: any application for government or non-government subsidies must comply with the “incentive effect”, subject to compliance with the subsidy conditions.
In order to respect the “incentive effect”, no binding commitment (signing a quotation; paying a deposit) may be made BEFORE having received the agreement in principle from the State or the electricity and natural gas supplier following an application for subsidy.

Call for tenders for operating aid for large-scale photovoltaic power plants

The operating aid enables companies to conclude a market premium contract for a period of at least 15 years. During this period, they receive remuneration based on the amount of electricity generated and fed into the grid.

This eighth call for tenders is open from 27 July to 30 October 2026 for a total capacity of 35 MW, divided into four lots. Depending on the lot, the maximum bid prices range from €80/MWh to €165/MWh.

Table 1: Overview of the different lots in the call for tenders for operating aid

• Here is the direct link to the published call for tenders.
• If you have any questions, please contact Klima-Agence.

An indicative multi-year schedule now makes it possible to anticipate upcoming funding opportunities.

Application periods and volumes to be submitted for the years 2026, 2027 and 2028

Call for tenders for investment aid for large-scale photovoltaic installations

As part of the competitive calls for tenders for photovoltaic projects, the government supports the deployment of large-scale photovoltaic installations through an investment subsidy. This financial support is intended to encourage companies to generate their own electricity.

This sixth call for tenders, launched by the Ministry of the Economy, is open from 17 July to 30 September 2026 and consists of three lots. Each lot includes sub-lots dedicated to photovoltaic installations equipped with energy storage systems. To be eligible for a “storage” sub-lot, the installation must have a minimum storage capacity of 1 kWh for every kWp of installed photovoltaic capacity.

Table 2: Overview of the lots under the investment aid call for tenders

• Here is the direct link to the published call for tenders
• If you have any questions, please contact Klima-Agence.

An indicative multi-year schedule now makes it possible to anticipate upcoming funding opportunities.

N.B. Government subsidies and calls for projects cannot be combined for the same project.

Klimabonus

The Klimabonus state subsidy scheme is available to both legal entities and individuals. However, pre-financing is not available to legal entities whose activities are subject to a business permit. These entities must follow the standard procedure and apply to the Environment Agency (AEV) after the work has been completed.

The subsidy rate for a photovoltaic installation is calculated based on the power of the system, using the following formula:

P_PV * (1.155 – (1.155 / 35) * P_PV) €

P_PV: peak electrical power of the photovoltaic solar installation concerned, expressed in kilowatt-peak (kW_p) and rounded to two decimal places.

This scheme does not impose any limit on the peak power of the installation. However, a ceiling of €10,000 per installation applies for systems with a capacity of 15 kW_p or more. The minimum eligible capacity is 2 kW_p.

A photovoltaic installation can be combined with a storage battery, which is also eligible to be a subsided. For further details, please refer to the measure “Installation of a battery storage system in your company”. Here you cand find more information on the application procedure for financial assistance.

• If you have any questions, please contact Klima-Agence.
• Please note: Compliance with the incentive effect requirement is not necessary under the Klimabonus scheme.

Tax relief for investment in an ecological and energy transition project

The tax relief is calculated based on the investments and operating expenses incurred as part of an ecological and energy transition project.
The tax relief rate is set at 18% and is applied directly to the amount of tax due.
This deduction can be combined with standard state subsidies.

For the project to be eligible, it must meet at least one of the following objectives:

• Improve the energy efficiency of a production process
• Improve the material efficiency of a production process
• Decarbonise a production process
• Reduce air pollution at the production site (excluding CO2 emissions)
• Produce or store renewable energy for self-consumption
• Promote the extended use of products through reuse

For certain objectives, minimum thresholds must be met.
To verify your eligibility and ensure that these thresholds are satisfied, it is recommended that the impact of the measure on one of the above conditions be certified by an expert or a design office.

Further details and conditions: Guichet.lu
For questions: Ministry of Economy – Bonus

Applying for permits

Don’t forget to check and obtain the permits required for the implementation of your photovoltaic project. To find out which procedures and permits may apply to your project, please consult the Procedures Manual.

After the installation of photovoltaic panels

• In case of self-consumption: submitting the application for self-consumption to the grid operator
  • For the surplus electricity to be injected: sign an electricity buy-back contract at the market price with a supplier
  • If participating in a call for tenders with investment aid: submit the request for payment of the aid via the tool on MyGuichet.lu.

• Apply for remuneration for the electricity produced by the photovoltaic system, depending on the specific situation:
  • Guaranteed feed-in tariff under the Klimabonus subsidy scheme (< 30 kWp) with the grid operator
  • Feed-in tariff without investment aid from the grid operator for installations > 30 kWp and < 400 kWp. From an installed capacity of 200 kWp onwards, membership in an energy cooperative may be required
  • Market premium with or without a call for tenders for photovoltaic installations from 400 kWp to 10 MWp with the grid operator and conclusion of a contract for the direct sale of the electricity with an agent who is normally a supplier.

• Scheduled maintenance of the installation

Maintenance

• Consider taking out a maintenance contract.