C-DRONE GUIDE · 1 SEPTEMBER 2026
Funding a Drone for Your Local Authority: DETR, DSIL, Green Fund, Price
A municipality wanting to equip its technical department with a drone rather than paying a contractor for every campaign, or funding a one-off drone mission without straining its operating budget: the question is not just "how much does it cost" but "who can pay for it." Three French state schemes — DETR, DSIL and the Fonds vert (Green Fund) — can cover part of these costs, provided they are filed under the right category at the right time. Here is how they work in 2026, what they actually cover for a drone project, and what a funding plan must respect to stay eligible.
Published on 1 September 2026, reviewed on 2 September 2026 — regulations in force as of September 2026.
Two kinds of spending, one budget status: investment
Before hunting for a scheme, place the expense correctly in the authority's budget nomenclature. A drone bought to equip the technical department is an ordinary capital expenditure (a tangible fixed asset) — nothing specific compared with buying a vehicle or a computer. A mission entrusted to a contractor, however, falls under capital or operating spending depending on what it produces: an orthophoto or a 3D model meant to durably enrich the municipality's geographic information system counts as investment, while a one-off service with no lasting deliverable (a simple communications flyover, say) is operating spending. That distinction gates access to the three schemes covered here: DETR, DSIL and the Green Fund only fund the investment budget — never a recurring operating expense, however useful.
For a drone mission awarded through public procurement, as covered in our guides to buying drone services through public procurement and to thresholds and the CCTP of a drone contract, this means a single framework contract can mix eligible lines (an initial survey feeding the GIS) with ineligible ones (site-progress photography with no lasting heritage value) — better to separate them at the specification-writing stage than to complicate the grant application afterwards.
DETR and DSIL: the State's two investment grants
The Dotation d'Équipement des Territoires Ruraux (DETR) and the Dotation de Soutien à l'Investissement Local (DSIL) each cover part of the capital cost for municipalities and their inter-municipal bodies (EPCI), through a different allocation mechanism:
- For DETR, reserved to authorities meeting population and fiscal-wealth criteria (typically rural ones), the priority project categories and ceiling rates are set each year, département by département, by the committee of local elected officials (CDIL) convened with the préfet — several such committees met in autumn 2025 to settle the 2026 programme. These categories therefore vary between départements: a drone project tied to road maintenance, risk prevention or digital transition may be eligible in one département and out of scope in the next.
- For DSIL, open more broadly to municipalities and EPCIs, the main priority categories are set nationally through a government instruction, reviewed every year: the 2026 campaign keeps an "ecological transition and climate-change adaptation" category with several sub-categories, from which some previously listed operations have been dropped (public lighting, for instance, is no longer a national priority category for 2026) — a reminder that these lists shift from one campaign to the next and need checking on every application.
In both cases, the subsidy rate follows a statutory 20% floor of the eligible expense excl. VAT, with no single national ceiling: the maximum rate for each project category is set locally (DETR) or by the national instruction (DSIL). Applications are filed online, through a process shared by both grants in most départements, on a calendar set by each préfecture — generally in the autumn or at the very start of the calendar year for that year's programme. DETR and DSIL generally cannot both fund the same operation.
The Green Fund: direct access, no call for projects
The Green Fund (Fonds vert), renewed for 2026 with a budget of €837 million, funds investment operations attached to three axes: strengthening environmental performance (energy renovation of public buildings, active mobility), adapting territories to climate change (natural-risk prevention — flooding, wildfires — plus renaturation and habitat restoration), and improving quality of life. Unlike DETR and DSIL, it does not run through calls for projects: applications are filed directly on the Aides-territoires platform, with no single national deadline, and a subsidy rate that varies by measure — roughly 25% to 80% of the eligible expense.
For a drone mission, the "climate-change adaptation" axis is often the most direct fit: a flood-zone survey feeding or updating a PPRi flood-risk plan, as covered in our guide to flood-zone mapping by drone, or a de-paving audit such as a cool schoolyard project fall squarely under this axis. The "environmental performance" axis opens the door for a thermal audit of school buildings ahead of an energy retrofit, while a municipal tree inventory or an urban heat island survey fit the "quality of life" axis. In all three cases, what makes the application eligible is not the drone itself, but the project it serves as a collection method for.
Building the funding plan: ceilings, stacking, self-financing
Three practical rules shape a funding application for a drone project, whether it is buying equipment or commissioning a contractor: pick the right category before filing (the same operation framed as "digital transition" or as "risk prevention" does not access the same DETR lines depending on the département), check the non-stacking rule between DETR and DSIL on the same operation — the Green Fund, on the other hand, can top up either one —, and respect the self-financing floor imposed by article L. 1111-10 of the French local government code: the project owner must itself fund at least 20% of the total public funding received, subject to the exceptions that article provides for certain operations. In practice, a €10,000 excl. VAT project funded 60% by DETR and 20% by the Green Fund leaves 20% to the municipality — exactly the statutory floor, a figure worth checking to the euro before filing.
To weigh buying an in-house drone against continuing to use a contractor, the reasoning mirrors our guide to depreciation and tax treatment of a professional drone: a grant lowers the net acquisition cost, but does not remove the need for a UAS operator declaration, pilot training, or the periodic renewal of theory qualifications — recurring costs none of the three schemes covered here fund, since they belong to the operating budget.
Frequently asked questions
Can a local authority combine DETR and the Green Fund on the same drone project?
DETR and DSIL generally cannot both fund the same operation — each finances a distinct project, even when the two applications are filed through a shared process. The Green Fund, however, can top up a DETR or DSIL grant on the same project, as long as total public funding respects the at-least-20% self-financing floor imposed on the project owner by article L. 1111-10 of the French local government code, subject to that article's own exceptions.
Does the Green Fund cover buying a drone outright, or only a mission handed to a contractor?
Both are possible, as long as the expense stays attached to an investment operation eligible under one of the current edition's three strategic axes — a drone bought to equip a municipality's technical department is treated like any capital equipment, on the same footing as a mapping or thermal-imaging mission entrusted to a contractor. What matters to the reviewing officer is the underlying project the drone or mission serves (flood-risk mapping, a thermal audit of public buildings, de-paving a schoolyard…), not the nature of the expense itself.
How do I know if a drone project fits my département's DETR priority categories?
These categories, along with the applicable ceiling rates, are set each year on a département-by-département basis by the committee of local elected officials (CDIL), convened with the préfet — usually in the autumn for the following year's campaign. They vary between départements and are reviewed annually: the DETR/DSIL practical guide published by the préfecture, or its local-authority relations department, lists the categories currently in force.