Charging your car on your own solar power sounds obvious: the panels are on the roof, the car is on the driveway, so why not connect the two? Until now the honest answer was "because net metering made it pointless". From 1 January 2027 that changes, and the maths suddenly flips in favour of charging on surplus. This article explains how solar-surplus charging works, what you need, where the 6 A limit bites, and what a normal household can expect from it.
Why 2027 changes the calculation
Under the Dutch net-metering scheme (salderingsregeling), every kilowatt-hour you export is subtracted from what you import, at the full retail price. Exporting at 13:00 and charging the car at 20:00 costs you nothing extra, so nobody bothered to line the two up.
On 1 January 2027 net metering ends. What you get for exported power after that is the feed-in compensation your supplier sets, minus any feed-in costs. Suppliers that have published their 2027 rates sit somewhere between 0.25 and about 4 cents per kWh net; a few are still provisional (overview per supplier, checked 23 September 2026). Power you import still costs roughly €0.25 to €0.30 per kWh.
So from 2027 a kilowatt-hour of solar that goes into your car instead of the grid is worth the import price you avoid, about €0.28, rather than the few cents you would have been paid for it. That is the whole business case in one sentence.
How surplus charging works
Surplus charging means the charger only draws what your panels are producing beyond what the house is using at that moment. Three things have to happen:
- Something measures the surplus. The cleanest source is the smart meter itself: the P1 port reports import and export per phase every second. A Lyvra P1 dongle or an Easee Equalizer does this. Some setups use a current clamp in the meter cabinet or a direct link to the inverter instead.
- Something decides. Software looks at the export figure, subtracts a safety margin, and works out how much current the charger may take without pulling from the grid.
- The charger follows. Chargers that can be controlled (Easee, Zaptec, Wallbox, go-e, NexBlue, or any OCPP charger) accept a new current limit every few seconds and adjust.
The car does not know any of this is happening. It sees a charger that sometimes offers 6 A and sometimes 16 A, and takes what it is given.
The 6 A floor, and why single phase matters
Every EV charger has a minimum current of 6 A per phase; below that the car will not start a session. On one phase that is 6 A × 230 V, about 1.4 kW. On three phases it is 4.1 kW, and the surplus has to be there on all three phases at the same time.
That floor decides how often surplus charging actually happens. A 4 kWp array on a Dutch roof peaks at 3 to 3.5 kW in summer. Subtract the house's 0.4 kW baseline and you have 2.5 to 3 kW of surplus: plenty for single-phase charging, not enough to ever reach the three-phase floor. So a charger that can switch to single phase (or one that is wired single phase) charges on solar most sunny days; a charger locked to three phases only does so with a large array.
Easee describes the same rule in its solar charging guide: surplus-only mode needs 6 A available on at least one phase, and on three phases the session is limited by the phase with the least surplus.
What a normal household gets out of it
The numbers below are for a typical Dutch setup: 10 to 12 panels (about 4 kWp, 3,600 to 4,000 kWh a year), a car that does 15,000 km a year (roughly 2,500 kWh of charging), and the car at home on some weekdays and most weekends.
- Roughly 1,500 to 2,500 kWh of the year's production is surplus you would otherwise export, most of it between April and September.
- How much of that reaches the car depends entirely on whether the car is home when the sun is out. A car that is away every weekday catches maybe 500 to 800 kWh. A car that is home two or three days a week catches 1,200 to 1,800 kWh.
- Each of those kilowatt-hours is worth about €0.25 from 2027 (import price avoided minus the small feed-in compensation forgone). That puts the value between €125 and €450 a year, on hardware you already own.
Two caveats. In winter there is almost no surplus, so solar charging is a summer story and the cheap-hours plan does the work the rest of the year. And if your supplier charges feed-in costs on top of low compensation, exporting can cost you money, which makes every self-consumed kilowatt-hour worth slightly more than the figure above.
Surplus mode versus "cheapest hours" mode
The two ways to charge smart are not rivals. Cheapest-hours charging looks at tomorrow's day-ahead prices and fills the car overnight when power is cheap; solar-surplus charging fills it during the day when your roof is overproducing. A good system runs both: it charges on surplus whenever there is any, and tops up on cheap night hours to make sure the car is full at the departure time you set. If the sunny afternoon already put 20 kWh in the battery, the night plan shrinks accordingly.
How to set it up in Lyvra
In the Lyvra app, solar charging is a preference on the charger, not a separate mode you have to switch on and off. Open your charger, tap Charging preferences, and enable Prefer solar charging. Set your usual departure time and target charge level once. From then on, Lyvra uses the smart-meter export reading to charge on surplus during the day, and plans the remaining kilowatt-hours in the cheapest night hours. A direct inverter connection is not required: the smart meter already knows what leaves the house.
The app is free on the App Store and Google Play. Download Lyvra and connect the charger you already have.
