Charging & grid
Bidirectional charging: what it pays in Switzerland
The idea of using the car as storage for the power grid is old. The Swiss legal basis is new. Since 1 January 2026 the grid operator refunds the grid usage fee for electricity you charged from the grid and later fed back. What that is worth can be calculated. It comes to 13,04 centimes per kilowatt-hour. For 100 francs to add up, 767 kilowatt-hours have to go back into the grid.
Three points are in the law
Bidirectional charging means the car does not only take electricity but also gives it back, into the building or into the grid. Without a rule of its own the grid usage fee would fall due twice: once on charging, once on whoever later draws the electricity fed back. The Electricity Supply Act removes that for storage facilities with end consumption.
- The refund. On request the grid operator refunds the grid usage fee for the quantity of electricity that is fed back after being drawn from the grid and stored, at most at the tariff applying at the time it was drawn. Article 14a paragraph 4 letter a StromVG, in force since 1 January 2026.
- The amount comes from the grid operator. It sets a refund tariff and deducts the amount from the grid usage fee on the next invoice. Articles 18d and 18e StromVV, in force since 1 January 2026.
- No second meter. The measurements for this proof may be taken with meters already present at the storage facility, in the charging station or in the vehicle. Article 14a paragraph 4bis StromVG, in force since 1 April 2026.
The third point goes back to a motion by Jürg Grossen of 20 December 2023, tabled in the National Council on the acceleration act (business 23.051). His reasoning names the ground. If an additional smart meter had to be installed at the operator’s cost for every one of these small storage units, that would be «economically and ecologically disproportionate» and would stifle vehicle-to-grid at birth. Grossen is president of Swiss eMobility; the association states that on its own site.
What the refund is worth
The ordinance says what the refund tariff consists of: the average energy component of the grid usage tariff for the tariff year at the place of feed-in, plus the costs for ancillary services, the electricity reserve, the grid surcharge and the measures under Articles 15a and 15b StromVG. In the federal official series for 2026 that is 10,73 centimes of grid usage and 2,30 centimes of grid surcharge, 13,04 centimes/kWh together. The municipality in the middle comes to 13,26. The two are 0,23 centimes apart.
For that to become 100 francs, 767 kilowatt-hours have to go back into the grid. That is 17,0 per cent of what a household in the lead profile H4 draws in a whole year, namely 4’500 kWh. The figure is an order of magnitude. Every grid operator sets its own refund tariff, and what they set nobody collects publicly.
What the largest Swiss field trial measured
From autumn 2022 to spring 2024 Mobility put fifty bidirectional Honda e into its regular car-sharing operation. The project was called «V2X Suisse» and is the largest trial of its kind in Switzerland so far. More than 6’600 people drove the cars, around 800’000 kilometres. Complaints that could be traced to the technology were almost non-existent.
Before the start the assumption was that a connected vehicle would bring one to two francs of flexibility revenue a day. At the end Mobility states: depending on market prices up to 2’000 francs per year and vehicle would have been possible — but the investment and operating costs were too high and were not covered in the test phase. Mobility has discontinued the bidirectional technology for the time being.
Up to 2’000 francs a year per vehicle would have been possible. The costs were still not covered.
Four conditions Mobility names
The trial ends with a list. What is missing for the technology to carry:
- The bidirectional charging stations have to get cheaper.
- More bidirectional vehicles are needed, and at lower prices — the market has developed more slowly than hoped.
- The distribution grid operators have to make feeding back more attractive.
- An interoperable standard is missing, so that different makes can charge and discharge at the same station. Mobility expects it by 2027.
Why the German calculation does not work here
In Germany the calculation runs on the price difference over the day. Solar electricity is almost free during the day and expensive after sunset. Former VW chief Herbert Diess sets this out in an interview with the Frankfurter Rundschau and names a bidirectional wallbox at around 2’000 euros that, according to calculations by The Mobility House, pays for itself in about a year. The German automotive industry association puts the same wallbox at more like 4’000 euros. Diess is chairman of the board of The Mobility House; the report we take this from says so itself.
A Swiss household in basic supply lacks the price difference this calculation rests on. Article 6 paragraph 3 of the Electricity Supply Act says: «Electricity tariffs are fixed for at least one year.» And anyone drawing less than 100 megawatt-hours a year may not switch supplier anyway; that is every household. What reliably comes back in Switzerland is the grid usage fee. The hourly price that carries the German calculation does not come on top.
Whether your car can do it at all
Feeding back requires the vehicle to be able to do it, over direct current with a charging station built for it, or over alternating current under ISO 15118-20. We know of no Swiss source that states this per model, and the model radar carries no field for it. We therefore give no figure. Anyone counting on this capability should have it confirmed in writing before the purchase, with the standard quoted.
With your own sun the arithmetic changes
Anyone with a solar installation charges the battery at midday with their own electricity and brings it back into the house in the evening. The refund falls away in that case: Article 14a paragraph 4 letter a StromVG refunds the grid usage fee for electricity that is stored and fed back after being drawn from the grid. Electricity from your own roof was never drawn. It still pays, only differently: what you consume yourself you do not have to buy.
| Route | centimes/kWh | where the figure comes from |
|---|---|---|
| Feed solar electricity in | 6,00 | minimum remuneration for installations below 30 kW, Article 12 paragraph 1bis letter a EnV |
| Consume solar electricity yourself via the battery | 27,70 | supply avoided, federal official tariff series, profile H4 |
| Charge grid electricity and feed it back | 13,04 | refund of the grid usage fee, calculated |
The gap between the first two rows is 21,70 centimes/kWh, and that is the real arithmetic of bidirectional charging. It lies 8,66 centimes above the refund. What the table leaves out are the storage losses: charging and discharging cost energy, and ten kilowatt-hours of sun become less by the evening. We know of no substantiated efficiency figure for bidirectional vehicles, so none is given.
Where it is measured, and who needs a meter
For a car the meter sits at the house connection, not in the charging station: Article 18g paragraph 3 StromVV declares the «quantity of electricity fed in by the mobile storage facility at the house connection point» to be the relevant one. Anyone who consumes the electricity in their own house instead of giving it to the grid feeds nothing in there — so there is no refund for that route either. And for a vehicle the ordinance says no more than that. To a stationary storage facility, paragraph 1 gives a rule of calculation: compare grid draw and storage every quarter hour, take the smaller value. For the mobile one it is missing. Anyone charging from both — sun at midday, grid at night — will not find in the ordinance how the two shares are separated.
The ordinance requires an intelligent metering system in one case only: where the storage facility is connected to a generating installation that is operated for self-consumption and is subject to the licensing requirement under Article 6 NIV (Article 18f letter a StromVV). That is the fixed installation connected by a licensed contractor. A plug-in balcony installation is plugged in and not permanently connected, so it does not fall under it. Where the line runs once a storage unit, more power or a vehicle connection are added is in no provision.
Charge cheap, give back dear?
The question comes up immediately, and the answer is in the ordinance. Article 18d paragraph 4 StromVV caps the refund at the «energy component invoiced» plus the cost items named — more than was paid never comes back. And Article 18e paragraph 2 calculates the refund tariff on a non-dynamic tariff even where a dynamic one applies to the storage facility. Charging when the grid fee is low and feeding back when it is high gains nothing on the grid fee. Zero is what the energy price becomes, never the grid fee: that falls due whatever the electricity costs.
What remains open is the attribution. Anyone who charges at work and discharges at home shifts costs from one grid connection to another — with a company car, between two people as well. Whether the refund applies when draw and feed-back happen at different connections, and who then counts as the «operator of the installation», is stated neither in the act nor in the ordinance; the register of gaps carries the case as lg33.
What this means for a purchase
- The refund is an entitlement, not an offer. It runs on request to the grid operator and appears as a deduction on the next invoice. 13,04 centimes/kWh is the order of magnitude, the exact tariff comes from your utility.
- The implementing provisions on metering are missing. The law permits existing meters, the requirements for them are for the Federal Council to set. The ordinance in its version of 1 July 2026 does not contain them.
- The big item is the charging station, and for Switzerland we have no substantiated figure for it. The 2’000 to 4’000 euros from the German debate are two statements by two interested parties, not a price series.
- Anyone justifying the purchase with this return is calculating with figures nobody publishes for Switzerland. As an addition to a car you want anyway, the matter is small in the arithmetic and secure in law.
Sources: Electricity Supply Act (SR 734.7) in its version of 1 April 2026 and Electricity Supply Ordinance (SR 734.71) in its version of 1 July 2026, both on Fedlex. In addition the Energy Ordinance (SR 730.01) in its version of 1 July 2026 for the minimum remuneration and the Low Voltage Installations Ordinance (SR 734.27) in its version of 31 October 2025 for the licensing requirement under Article 6. Motion Grossen Jürg of 20.12.2023 on business 23.051 in the papers of the Federal Assembly. Field trial: Mobility on «V2X Suisse», 19.06.2024. German debate: elektroauto-news.net, 11.09.2026, after an interview in the Frankfurter Rundschau. Tariff figures: ElCom tariff data 2026 via LINDAS.
Transparency: the 13,04 centimes/kWh are calculated from the components of the household tariff (grid usage plus grid surcharge of the federal official series for 2026), not from reported refund tariffs. Those do not exist as a series. What the ordinance describes as the refund tariff is the energy component at the place of feed-in; our figure is the corresponding item of a household tariff. Levies to canton and municipality and the metering costs are not included, because the ordinance does not name them. Medians are moreover not additive: the sum of two medians is not the median of the sum. The figures are recalculated from static/gemeindetarife.json at every build and searched for in the text, in all four languages; the register of gaps carries the open point as lg32.
