Solar panels are hot idea but beware pitfalls

Solar photovoltaic panels cost a fifth what they did 15 years ago, so many people are looking again at fitting them – even though the price EDF pays for electricity has tumbled.

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But the industry struggles to shake off a dodgy reputation, with papers including Connexion featuring cases where people have lost thousands, mainly through cold-call offers for systems paid for with a bank loan.

Now DIY kits can give a home setup of 36kW for less than €5,300, including panels, mounts for a tiled roof, inverters, cables and plugs. There is also some state aid but to get this or to sell power to the grid, work must be done by an RGE-registered artisan.

Environment agency Ademe has produced an updated 2019 leaflet on domestic photovoltaic (PV) panels.

Its first advice, before installing a system, is to make savings by reducing your power usage as much as possible. Then, when sourcing panels, make sure they meet French NF-EN-CEI 61215 and NF-EN-CEI 61730 standards on manufacture and safety.

Most domestic solar PV systems use between 10m2 and 30m2 of panels and the roof is usually the best place – as long as it faces south. You can also set panels in angled frames in the garden, on walls or build a porch or conservatory to create roof space, as long as they face south. However, you may face “garden shed tax” – see here.

Solar PV gives DC output so you need an inverter to change to household AC and these need replacing or servicing every 10 years or so, at about 30-60 centimes per watt.

More expensive micro-inverter systems have several small inverters, so the performance of individual parts of a large system can be monitored.

Financial planning

Before signing a deal, Ademe says to look at some simple financial planning. Today there are three usage models available (these may change with governments):

  • Auto consumption, where you use power you have produced, then, at night, switch to grid power. You can extend this with battery packs – like those in electric cars, where prices have also fallen – to use your own power at night too, but Ademe warns such systems are still double the price of alternatives;
  • Auto consumption and sale, where you use your own electricity and sell any surplus to the grid;
  • The historic model, where all the power produced is sold to the grid and the house uses grid electricity.

Obviously, the financial picture depends on the tarifs d’achat, which are set by the government and which have been on a downward trend.

The latest tariff, found at, is all but incomprehensible for most people. Repeated attempts by Connexion to find a clear tariff grid from the authorities failed.

Ademe’s main leaflet says only that tariffs should allow installation to be repaid in 10-20 years. Ademe and the Commission de Régul­ation de l’Energie did not answer requests for a clear table of tariffs. Readers with new systems say they get around six centimes per kWh, a fraction of the 65c/kWh for people who installed 10 years ago.

Those with set-ups less than 100kWc (kilowatt-crête maximum output) who sell all the power to the grid face different purchase tariffs at 3kWc, 9kWc, 36kWc and 100kWc.

Selling surplus power from a system of less than 100kWc can give a state prime à l’investissement – paid over five years – plus a fixed tariff, determined by the previous formulae and indexed to energy price over 20 years.

The advantage of auto consumption models is that in addition to the small fee for selling power, you are insured against future power price rises.

Primes for new projects are reviewed quarterly depending on demand and the power they add to the grid, but once an offer is fixed it will not be affected by the change, and in theory should cover 30% of installation costs.Ademe says people fitting panels to sell all output to the grid face costs of €500-€1,500 to be linked up.

Those selling only surplus output or who feed the grid surplus for free – possible with systems of less than 3kVa (kilovolt amp, apparent output) – use a simplified link at around €50.

Other systems may face extra costs. Total auto consumption set-ups (with batteries) face no grid link costs but you must sign an agreement with the grid manager, and be sure the system is the right size for your needs.

If you sell all the power your panels produce to the grid, you will need two Linky smart meters, one for outgoing electricity and one for the incoming.

Only one Linky is needed to sell surplus power then switch to grid.

Ademe says the cost of fitting a roof- integrated system is €2-€3/watt (a kW is 1,000 watts) but can rise with extra services or complications. Systems built on top of the roof are less pretty but are cheaper – and leak-proof.

If the building is at least two years old and the setup is under 3kW, you pay just 10% VAT on kit and fitting if work is done by RGE artisans. Larger systems pay 20% VAT.

Grid upkeep charges of €40 a year are also levied if you sell all your power and €11 if you sell your surplus only.

Ademe says running costs are low but you must check it works properly.

House insurance can cost up to an extra €50 a year.


There is no income tax if you sell power from a system under 3kW (meaning about 25m2 of panels) but above that you declare income for tax. For 10kW+ systems it may be wise to set up a micro-entreprise for tax.

Some communes also give partial or temporary exemption of some of your taxe foncière on buildings used for solar PV systems after set-up.

Get a free, independent evaluation of a system’s financial aspects at new government service FAIRE (

Local administration

Formalities to install a system are your responsibility, even if many firms selling systems do your paperwork.

For an existing building, you make a simple planning permission application, déclaration préalable, at the mairie. You do not need formal planning permission but must get a certificat de non-opposition from the mairie. New-build installations have to be included in the file for the permis de construire.

Complications can arise if your commune has by-laws on things like roof tile colour, or if you live near a historic monument or a protected site. You might have to get permission from the departmental architects.

In flats or a copropriété you need the other copropriétaires’ agreement.

Responsabilité civile insurance is obligatory and dommages aux biens insurance covers accidents. They may already be in your household cover.

They did it

Ed and Jennifer Foord had always thought about fitting solar PV panels at their Charente-Maritime home. It has a large south-facing roof – and a son-in-law in England was doing well out of his system.

A cold-call spurred them. “Their offer was linked to a 20-year loan, complicated tax rebates, and had expensive panels and a heat pump hot water system, which was double the price of that on the internet,” said Ed.

“Their price for panels alone was €20,000, which is what they might have cost 15 years ago. They were charlatans, but it prompted us to ask locally.”

A local firm fitted a 3.5kWh system and another the inverters and a web output monitor, for about €10,500.

Ed said: “That part was fine and we are happy with the work and service, and they helped tremendously with the admin to get it up and running, but relations with Enedis and EDF had us tearing our hair out.”

Jennifer said: “I was so frustrated I burst into tears in front of the computer. It is obvious they resent dealing with domestic setups. They do nothing to make it easy.” A neighbour gets 65 centimes per kWh for a 10-year old system but the Foords get 6c/kWh as they use their own power, selling excess to EDF on a 20-year contract.

As producers, they also paid €500 to be linked to the grid as they did not have a Linky meter... then found their village was getting Linkys a couple of months later.

A huge problem over invoicing EDF blew up. Ed said: “Everything was difficult. Even their ‘how-to’ video was completely wrong. Then the artificial-intelligence help-box profiled us as ‘young and not good with figures,’ which led to a massive humour failure, I can tell you.”

They eventually got a cheque for a disappointing €380. “Not a great return on €10,500,” said Jennifer, but they got a €1,100 rebate on their standing order payments.

“We use a lot of power to heat house and pool and it is a way to pay a bit back to the environment for our high use, but I do wish it could be done without the stress we have had to put up with from EDF and Enedis.”

‘No-brainer’ turned out to be an expensive disaster

Getting solar panels for their house in Aude seemed a “no-brainer” for Pat and Damien Handslip, as they get lots of sun, but it was an expensive mistake.

Three firms gave quotes estimating payments of from €1,000 to €1,500 a year – paying off the system in around 10 years – but Pat said: “We have never seen anything like that. Our best has been €480 and the worst €420.

“What the three companies did not take into account was the fact our roof faced east and not south!”

Adding to the problem was that the local firm they chose went bankrupt just after doing the work and before they received the paperwork to get payments from EDF.

“We were very lucky. We were in town on other business and I said we should just go to the office for the paperwork as we had not received a reply to phone messages.

“The door was locked and there did not seem to be anyone around. By chance, the managing director came out of a side door and I asked him to complete the papers. He went in and came back with the paper signed and stamped. If he had not, we would have got nothing at all.”

Pat, who had a career in business and NHS management, claimed against UK insurers, who offered €1,000.

“I did not have the strength to fight for more,” she said.

“We just have to look on the bright side: we gained a veranda which we enjoy in summer and is useful for drying washing, and we have done a bit for the environment.”

Six steps to setting up your system

ADEME’S typical project for domestic solar PV systems is in six stages:

  • Choice and estimates: get an evaluation from FAIRE ( to check figures and get installers’ devis;
  • Finance and insurance – check if you can get help from your commune, department or region. Speak to the bank about what loans are available. Check you are insured;
  • Obtain planning permission from the mairie;
  • Request to be linked to the grid: You have to apply to Enedis with the documents obtained in the earlier stages, by filling out a form on the Enedis Connect website. Enedis must say within 10 days how long it will take to offer you a proposition de raccordement (PDR) and a contract number (contrat d’accès au réseau et d’exploitation – CRAE). These will be sent in one to three months and you must sign them and return within three months;
  • Do work and link to grid: installer fits system and provides a consuel, an attestation sur l’honneur the work was done, plus guarantees related to the panels and the rest of the system. Send consuel to Enedis, which then does the work needed to link you to the grid. Make sure it all works, fill out the fiche de jalonnement showing sites of electricity production;
  • EDF is required to buy your powerat the tariff agreed, and sends a contrat d’achat. Sign and return it with the installer’s attestation sur l’honneur.