Understanding a photovoltaic installation: panels, inverter, battery, Linky

Photovoltaic panels

The photovoltaic panel is the central element of any solar installation. It works through the photovoltaic effect: when photons strike a silicon semiconductor, they free electrons that move through an electrical circuit, generating direct current (DC). This current is then converted into alternating current by the inverter.

In 2026, three technologies dominate the French residential market, with different levels of efficiency, price and thermal performance. The choice depends above all on your available area, your budget and your geographic exposure.

Whichever technology you choose, always demand two warranties from your installer: a product warranty covering manufacturing defects (12 years for monocrystalline, 15 years for TOPCon, 25 years for HJT) and a performance warranty of 25 to 30 years ensuring an output of at least 80–84% of the rated power at the end of that period.

Higher efficiency = fewer panels needed

The difference in efficiency between standard monocrystalline technology (20%) and HJT (24%) may seem modest, but it is significant on a roof with a limited area. To produce 5,000 kWh/year, a roof fitted with HJT panels will need about 15 to 20% less area than with standard monocrystalline. On a small 20 m² roof, this gain is decisive.

However, the extra cost of HJT (0.48–0.68 €/Wp versus 0.28–0.38 €/Wp for monocrystalline) lengthens the payback period. Our simulator takes these parameters into account to show you which power and technology combination optimises your payback period for your profile.

The solar inverter

The inverter is the brain of the solar installation. Its main role: to convert the direct current (DC) produced by the panels into 230V 50Hz alternating current compatible with the household network and the Enedis grid. It also includes an MPPT algorithm (Maximum Power Point Tracking) which continuously optimises output by following the panels' maximum power point according to sunshine and temperature.

In 2026, three types of inverter coexist on the home market, with different trade-offs between cost, performance and shading management.

MPPT: optimising every watt produced

All modern inverters include at least one MPPT tracker. The algorithm continuously measures the voltage and current of each string of panels to identify the maximum power point and adjust operation to it. A good-quality inverter has 2 to 4 independent MPPT inputs, making it possible to manage strings with different orientations (east/west, east/south, etc.) without mutual losses.

With microinverters, each panel has its own built-in MPPT: if a panel is partially shaded, only that panel is penalised, and the others keep working at their maximum power. This is the main technical advantage of microinverters in configurations with partial shading.

The Linky meter

The Linky meter is the smart meter of Enedis, the grid operator. It has been rolled out since 2015 and is now present in more than 95% of households connected to the French electricity grid. Unlike the old mechanical dial meters, the Linky meter is an electronic device able to measure energy flows in both directions and to transmit this data remotely to Enedis.

In the context of a grid-connected photovoltaic installation, the Linky meter plays a central role because it measures two flows separately:

• Import: the energy drawn from the grid by your household (at night, on cloudy days, when generation is insufficient).
• Export: the energy produced by your panels and not consumed immediately, fed back into the Enedis grid.

These two measurements are completely independent: there is no instantaneous netting between what you export and what you import. The exported energy is bought back by EDF OA (the EDF buy-back obligation scheme) at the applicable rate (0.011 €/kWh for the surplus since June 2026, ministerial order (arrêté) of 1 June 2026), and the electricity you import is billed at the rate of your contract with Engie, EDF or another supplier.

No special step for the Linky meter

Contrary to a common belief, you have no steps to take regarding the Linky meter for your solar installation. Your installer submits the connection request to Enedis (CACSI, Convention d'Autoconsommation avec Injection, the self-consumption agreement with grid injection), and Enedis remotely programs your Linky meter to activate two-way measurement at commissioning. No compulsory visit, no extra cost.

You can view your consumption and generation data through the Enedis customer account (enedis.fr) or the Enedis mobile app, with a history at 30-minute intervals. Partner APIs also allow your installer or your monitoring system to retrieve this data automatically.

Battery storage

A storage battery keeps the solar energy produced during the day so that it can be used in the evening, at night or on cloudy days, precisely when generation is insufficient. It solves the main drawback of solar energy: the mismatch between generation and consumption.

A typical household without a battery generally reaches a self-consumption rate of 20 to 50%, depending on its consumption profile:

• 20–30%: away during the day (consumption in the morning and evening).
• 30–50%: at home during the day (remote working, retirees).
• 45–60%: consumption in step with generation (e.g. swimming pool, air conditioning).

With a well-sized battery, this rate can rise to 60 to 75%, reducing your electricity bill by the same proportion. The typical gain is +15 to +30% in self-consumption rate.

The two reference technologies

In 2026, LFP (Lithium Iron Phosphate / LiFePO4) technology is the undisputed benchmark for home storage. Its chemical stability, high cycle count and long service life make it the safest and most economical choice over time. NMC technology can be considered if bulk is a major constraint.

Warranties and manufacturers

The main brands present on the French home market in 2026 include BYD (Battery Box Premium LFP), Pylontech (Force H2), Huawei (LUNA2000), SolarEdge (Energy Bank), Enphase (IQ Battery 5P), Sungrow (SBR200), GoodWe (Lynx Home F) and SonnenBatterie. The standard warranty is 10 years or a defined number of cycles (often 3,000 to 6,000 depending on the technology). Check that the warranty does cover the residual capacity (generally 70% at the end of the warranty period).

How it all works together

A complete home photovoltaic installation involves several components that interact in real time, depending on the level of solar generation, the household's consumption and the battery's state of charge (if there is one).

Normal flow: a sunny day

In the middle of the day, the panels produce a direct current (DC) that feeds the inverter. The inverter converts it into 230V alternating current that can be used in the home. The energy is first used to power the appliances that are running. This is direct self-consumption, the form that is most valuable financially.

If generation exceeds instantaneous consumption, the surplus is either stored in a battery (as a priority, if it is not full) or exported to the grid through the Linky meter, which measures the volume exported. In installations without a battery, any surplus is exported immediately.

Evening and night flow

When solar generation drops to zero (sunset, thick cloud), the household is powered first by the battery, if it is charged. Once the battery is empty, or if there is no battery, the Linky meter records grid import, billed at the normal rate.

Solar generation and consumption are never perfectly in step, which is why the self-consumption rate rarely exceeds 45% without a battery for a typical household that uses most of its energy in the morning and evening.

Choosing according to your profile

There is no universal configuration: the best combination of components depends on your roof, your budget, your consumption habits and your goals (maximum financial return vs. energy independence). Here are three typical profiles to guide your choice.

These profiles are starting points. Our simulator analyses your precise situation (address, consumption, roof area, orientation) and will help you find the optimal sizing, with complete, personalised results.

What does not change whatever the configuration

• The Enedis connection is compulsory for any installation that exports to the grid, whichever technology is chosen.
• The declaration at the town hall (prior declaration of works) is required in the vast majority of cases, and your installer generally takes care of it.
• The self-consumption bonus (prime à l'autoconsommation, paid by EDF OA) has been abolished since 1 June 2026 for all new installations. Installations connected before that date continue to receive it.
• VAT at 5.5% applies to panels and inverters for homes, regardless of their age. Batteries remain taxed at 20%.

Frequently asked questions about the components

Glossary

Acronyms and technical terms used in this article.

AC

Alternating Current. The current produced by the inverter, compatible with the home's 230 V 50 Hz network.

CACSI

Convention d'Autoconsommation avec Injection (self-consumption agreement with grid injection). A contract between the installer, Enedis and the supplier that allows the surplus to be sold to the grid.

DC

Direct Current. The current produced by the solar panels, converted into AC by the inverter.

EDF OA

EDF Obligation d'Achat (EDF's buy-back obligation). The EDF subsidiary responsible for buying back the electricity exported by home producers at the rates set by the CRE (the French energy regulator).

HJT

Heterojunction Technology. A panel technology combining crystalline and amorphous silicon, with an efficiency of 23–25%.

Export

Energy produced by the panels and not consumed immediately, fed back into the Enedis grid and measured by the Linky meter.

kWp

Kilowatt-peak. Unit of nominal power of a panel or an installation, measured under standard test conditions (STC: 1,000 W/m², 25 °C).

kWh

Kilowatt-hour. Unit of energy: 1 kWh = the consumption of a 1 kW appliance running for 1 hour. Used to measure annual generation and consumption.

LFP / LiFePO4

Lithium Iron Phosphate. The battery chemistry recommended for home use: stable, hard to ignite, 3,000 to 6,000 charge/discharge cycles, 10–15 years of service life.

MPPT

Maximum Power Point Tracking. An algorithm built into the inverter that continuously adjusts the electrical parameters to extract the maximum power from the panels.

NMC

Nickel-Manganese-Cobalt. An alternative battery chemistry to LFP, more compact but less durable in cycles and more sensitive to heat.

PVGIS

Photovoltaic Geographical Information System. A European database (JRC / European Commission) providing weather and solar irradiation data to estimate generation according to location.

Payback

Return On Investment (ROI). The number of years after which cumulative savings equal the cost of the installation (payback period).

Import

Energy drawn from the Enedis grid by the household (at night, on cloudy days, when generation is insufficient), billed at the rate of the supplier contract.

String

A chain of panels connected in series to the same central inverter. Shading on a single panel penalises the whole chain.

TOPCon

Tunnel Oxide Passivated Contact. A high-efficiency panel technology (22–24%) thanks to passivation of the rear face, which reduces electron recombination losses.