Solar-EV synergy: real figures
An EV traveling 15 000 km/year consumes around 2 700 kWh (18 kWh/100 km for a modern vehicle). At the network rate (CHF 0.27/kWh), the annual cost is CHF 729. With 60–70% solar km (1 890 kWh self-consumed at CHF 0.01–0.02/kWh marginal cost), the cost drops to CHF 200–250/year — annual savings of CHF 480–530 on EV charging alone.
Three approaches to solar charging
Approach 1 — Scheduled charging: schedule the charging station for 10h–16h through its app. Simple, with no additional investment. Effective if you are at home during the day or your EV only leaves at the end of the day. Approach 2 — Priority solar charging station (e.g.: myenergi Zappi, Wallbox Eco+): the terminal measures the solar surplus and dynamically adjusts the charging power (from 1.4 to 7.4 kW) to exactly consume the surplus. CHF 600–1 200 additional cost vs. standard terminal. Approach 3 — Integrated EMS: the EMS of the inverter (EMMA, SolarWeb) controls the compatible terminal. The most fluid and comprehensive solution but requires an OCPP or Huawei compatible terminal.
Your EV as mobile storage: V2H
V2H (Vehicle to Home) allows the EV battery to return energy to the home – transforming the EV into a domestic battery. In 2026, V2H compatible EVs in Switzerland are still rare (Nissan Leaf, Mitsubishi Outlander PHEV with CHAdeMO adapter). EVs with CCS bidirectional charging (European standard) are gradually arriving (Volkswagen ID.4, Hyundai IONIQ 5/6). An EV with a 60 kWh battery can theoretically power a house for 5–7 days.
Planning: how to integrate EV from the design stage
If you are simultaneously planning solar panels and purchasing an EV: (1) Slightly oversize the installation by 2–3 kWp for the EV. (2) Provide a pre-wired conduit between the electrical panel and the garage (or carport) when installing panels — marginal cost, but avoids heavy work later. (3) Choose an 11 kW three-phase terminal (even if your current subscription is single-phase) to maintain future flexibility. (4) Choose an OCPP-compatible terminal for future integration with your EMS.