Three quotes, three different system sizes, three different prices — and no clear basis for comparison. Here is what to look at, what to ask, and how to identify whether you are being quoted what you actually need.
The most important thing to understand about solar installer quotes in France is that they are not engineering assessments. They are commercial proposals — written to present the installer's preferred system in the best possible light, at a price that reflects their margin structure and supplier relationships.
That does not make them dishonest. But it does mean that comparing three quotes from three different installers is not the same as comparing three independent assessments of what your property needs. You are comparing three different sales pitches, each built on different assumptions, different brands, and different incentives.
Understanding that distinction is the starting point for making a good decision. Everything else follows from it.
Getting energy advice from an installer is like asking a car dealership whether you need a new car. They cannot be objective — the incentive runs in one direction. This is not a character problem. It is a structural one. The adviser who charges a fee for independent analysis has no financial interest in what you buy, or whether you buy at all.
What is the proposed system size in kWp, and how was that size determined? If the quote does not explain the sizing basis — consumption data, PVGIS yield modelling, export tariff assumptions — it is an estimate, not an engineering calculation. Ask to see the calculation.
Monocrystalline PERC, TOPCon, and HJT panels have different efficiency ratings, temperature coefficients, and degradation profiles. The quote should specify panel model and key performance parameters — not just brand and wattage. A cheaper panel per watt may degrade faster and deliver less energy over the system lifetime.
String inverters, hybrid inverters, and microinverters each have different cost profiles, failure modes, and battery compatibility. A hybrid inverter is required if battery storage is included now or planned for the future. The quote should specify inverter model, rated power, and — crucially — whether it is correctly sized for the array.
LFP (lithium iron phosphate) batteries have a significantly longer cycle life than NMC (nickel manganese cobalt) batteries — typically 6,000+ cycles versus 3,000–4,000. If a quote specifies a battery by brand name only, ask for the chemistry. Warranty terms should cover both years and total energy throughput, not years only.
Installations must be carried out by an RGE-certified installer for grant eligibility. QualiPV is the specific qualification for photovoltaic work. Certification must be current at the time of installation — not just at the time of quote. Check the RGE directory at qualit-enr.org directly, not just the installer's word for it.
Connecting a solar installation to the Enedis grid requires a formal Proposition Technique et Financière (PTF) from Enedis. This defines the connection terms and costs — which can range from a few hundred euros to several thousand depending on your connection point. A quote that does not include confirmed raccordement costs is incomplete. Beware of "to be confirmed".
MaPrimeRénov' must be applied for before work begins — not after. CEE gestures have specific technical requirements that must be met by the installed equipment. TVA 5.5% applies to renovation work on properties over two years old. If a quote includes grant figures, verify the sequencing is correct and that the equipment listed meets the relevant technical requirements.
French consumer law limits advance payment deposits for work under certain thresholds, but solar contracts are often structured with large upfront payments. Check payment milestone structure, warranty periods for both equipment and workmanship, who is responsible for Consuel certification, and whether EDF OA registration is included in the service or charged separately.
Grant sequencing is one of the most common sources of lost money in French solar projects. The rules are specific and the penalties for getting them wrong — forfeiting the grant entirely — are real.
Available for principal residences (résidences principales) only — not second homes or holiday lets. The property must be over 15 years old. The application must be submitted and approved before work begins — not before the quote is signed, but before the installation starts. The installer must hold current RGE certification at the time of work. Income thresholds apply and determine the grant level. Note: from January 2026, certain measures including wall insulation via the Geste route are no longer eligible — verify current eligibility before including in your planning.
CEE grants are available for a wider range of properties than MaPrimeRénov' and are administered through energy suppliers rather than ANAH. The grant amount depends on the energy saving achieved by the measure and the current CEE market price. Eligibility requires that the work meets specific technical standards (fiches d'opérations standardisées) — installers must be able to demonstrate compliance, not just claim it.
The reduced VAT rate of 5.5% applies to energy renovation work on residential properties over two years old, carried out by qualified contractors. This is not a grant — it is a rate reduction that should be reflected directly in the installation price. Any quote for eligible work that applies the full 20% TVA rate is either incorrectly structured or the installer is not registered for the reduced rate.
Stone farmhouses, maisons de maître, and rural Périgord properties have characteristics that generic solar installer quotes rarely account for correctly. The combination of old construction, mixed heating, variable insulation, complex roof geometry, and frequent proximity to listed monuments creates a planning and technical context that requires local knowledge.
The Dordogne RGE installer market is active but variable in quality. Some installers are excellent. Others offer systems sized for their margin rather than the property. Being able to verify RGE status, check references, and compare quotes against an independent specification makes a significant difference to both the quality and the cost of what gets installed.
For Dordogne clients, an on-site assessment is available across the full department (24). This is the only way to properly assess ABF constraints, roof geometry, shading, and heating system interaction in a single visit. Remote desktop reviews are also available for clients elsewhere in France.
Send your quotes for an independent review. A written comparison — covering specs, RGE status, grant compliance, and contract terms — is returned within three working days.