On March 26, 2025, the French Ministry of Economy officially enacted a significant revision of the S21 tariff framework, in place since 2021, which regulates access to electricity purchase contracts for solar installations on buildings, hangars or shading structures with an installed capacity of up to 500 kWc. The new decree introduces stricter and more segmented criteria, adds industrial requirements, and moves part of the sector toward competitive auctions. This has already raised concerns within the French solar industry.

End of automatic eligibility for 100–500 kWc systems

The most notable change is that, starting from the date of the next call for tenders, installations between 100 and 500 kWc will no longer be automatically eligible for regulated feed-in tariffs. Instead, they will be subject to competitive bidding procedures, except for those that have already applied under the previous regime.

Electricity purchase conditions for systems with a peak capacity strictly greater than 100 kWp and less than or equal to 500 kWp will be subject to change once the tendering process opens. Until that date, the previous decree from October 6, 2021 remains applicable. After the call for tenders opens, this new decree will apply only to installations with a peak capacity of up to 100 kWp.

In addition, the decree mandates that the main components must not have been previously used for more than three months, unless refurbished with a functioning warranty. It also introduces a mandatory €10,000 financial guarantee to secure project execution for systems above 100 kWc.

For installations with capacity above 100 kWp, producers must submit proof of a financial guarantee to ensure project implementation. The €10,000 guarantee can be constituted either by a deposit with the Caisse des Dépôts et Consignations or a first-demand guarantee, with a list of required documents for its setup and release.

New tariff and premium levels by power segments

The revised scheme introduces differentiated tariffs and investment premiums based on system capacity, distinguishing between full-feed-in sales and surplus injection.

For full-sale installations:

• 9 to 36 kWc: tariff Tb of €0.1295/kWh

• 36 to 100 kWc: €0.1126/kWh

For surplus-injection systems:

• Prime Pa: €0.08/Wc (up to 9 kWc)

• Prime Pb: up to €0.19/Wc (up to 36 kWc) and €0.10/Wc (up to 100 kWc)

• Surplus tariffs: TPa €0.04/kWh and TPb €0.0761/kWh

These new values apply to projects submitted from April 1, 2025. A transitional regime applies for those filed between March 27 and 31.

Industrial resilience becomes mandatory

From July 1, 2026, and gradually until 2028, the government will require that PV modules and cells meet a “resilience” criterion, as defined under the European Net Zero Industry Act.

This means that manufacturers must not produce more than 50% of their output outside of Europe, aiming to reduce the bloc’s technological dependence on Asia.

“The notion of resilience falls within the framework of the European regulation,” the text clarifies, specifying that compliance will be assessed at the corporate group level, not just the manufacturing subsidiary.

Warnings from the solar sector: limited visibility and penalized self-consumption

The new decree prompted mixed reactions from the industry. Both the Syndicat des Énergies Renouvelables (SER) and Enerplan welcomed the non-retroactive nature of the measures and the maintenance of the current tariff regime until July 1.

“I welcome the fact that public authorities considered the input from the sector, the CRE and the Conseil Supérieur de l’Énergie. The industry’s mobilization was decisive. The specter of a moratorium is receding, but we need to return to the negotiating table quickly to exit this transitional phase and restore visibility for professionals after this chaotic period,” says Daniel Bour, president of Enerplan.

Jules Nyssen, president of SER, adds: “The changes introduced today are a step in the right direction as they will prevent a sudden market collapse. However, it is essential that the simplified auction mechanism takes over from this tariff decree as early as July. Otherwise, we will have only delayed the ‘cliff-edge’ effect by a few months. And it is incomprehensible that the government didn’t wait for the reduced VAT rate to come into effect to partially offset the cuts imposed on self-consumption.”

A precarious regulatory balance

Both associations agree that the reform temporarily averted a collapse of the sector, but emphasize that “self-consumption has been sacrificed and the risk of a moratorium persists.”

“Other announcements remain very unfavorable for photovoltaic solar energy. The residential segment will face a threefold reduction in premiums and tariffs as of the entry into force of the new decree—without alignment with the implementation of reduced VAT,” the joint statement notes.

Furthermore, if the S21 tariff order is to be replaced by a call for tenders for the 100–500 kWc segment, many uncertainties remain—particularly regarding volumes and frequency of the sessions to be opened.

While the reform aims to align with the Green Deal Industrial Plan and the Net Zero Industry Act, its success depends on the clarity, regularity and volume of future auction rounds.

Enerplan and SER urge the government to ensure stability now:  “We call for further discussions to provide visibility to the solar sector. We need simple and sizable tenders from July onward,” they stress.

Click here to download the decree