Ferroamp
Ferroamp is a Swedish hardware manufacturer whose single shared bidirectional inverter makes V2G an add-on for existing solar/battery customers, while the market-facing aggregator role in its pilots is played by Varberg Energi.
Its V2G pilots with Varberg Energi (villa/EV in 2025, electric boats in 2026) show how a hardware vendor and a utility can split the work, at a time when Varberg Energi sees the OEMs' choice between "closed" and "open" charger models as decisive for how V2G develops.
Ferroamp is a Swedish manufacturer of DC/AC power-conversion hardware for behind-the-meter energy systems, founded by Björn Jernström.
Technology
Ferroamp’s core product integrates solar generation, battery storage, and EV charging through a single modular system built around a central inverter, bidirectional by design from the start. Rather than treating each function (solar inverter, battery inverter, EV charger) as separate hardware, the system shares one conversion layer: it can export power to the grid or draw AC from the grid and route it into an EV or stationary battery. Because the underlying hardware is already shared, V2G is offered to existing solar/battery customers as an add-on to their current installation rather than as new, dedicated equipment.
Role in V2G
Varberg Energi’s Mats Balkö frames the choice facing car makers as a fork between a “closed” model — the customer must pick a specific charging box and the car maker takes over control of the home — and an “open” model — the customer can use different charger brands and integrate across the car maker’s and other home products. Ferroamp’s Björn Jernström likewise sees the car makers as the key to V2G taking off, and stresses that they must be clear about which models may use V2G and how much power and how many kWh may be used. Ferroamp has collaborated with Varberg Energi on smart energy services since 2023. (Source - Så Kan V2G Gå Från Projektform Till Marknaden (2025))
Varberg Energi pilot (May 2025): Ferroamp and Varberg Energi demonstrated an EV connected to a villa via Varberg Energi’s own app, linking the vehicle into Varberg Energi’s energy trading (energihandel) and producing both revenue and smart energy savings for the customer. Varberg Energi states it can connect V2G via either AC or DC. (Source - Så Kan V2G Gå Från Projektform Till Marknaden (2025))
Note on platforms: Varberg Energi is also a customer of Fever Energy, which says it became Varberg Energi’s primary platform for distributed energy. The Ferroamp pilot sources describe Varberg Energi’s own app; neither source says whether that app runs on Fever.
Extension to electric boats (August 2026): the same Ferroamp/Varberg Energi collaboration extended to a new asset class — recreational electric boats, with Volvo Penta supplying the marine battery/charging technology and the Västra Götaland Region funding the pilot. Two boats were connected to the grid; the release states the system “meets the requirements of the fastest ancillary services.” Varberg Energi acted as aggregator, signalling when the batteries should charge or discharge. The pitch: many boats sit on land through the winter, so their availability is known in advance (which ancillary-service markets require), and their batteries can often offer around ten times the capacity of residential batteries. (Source - Ferroamp Varberg Energi Volvo Penta Electric Boat V2G Pilot (2026))
Related pages
- Vehicle-to-Grid — V2G taxonomy, AC/DC business-model discussion, ecosystem actors table
- Effekthandel Väst — the unrelated Göteborg Energi–Volvo Cars V2G pilot, for contrast with Ferroamp/Varberg Energi’s approach
Data gaps
- Ferroamp’s presence, if any, in DSO-run local flexibility markets (Effekthandel Väst, SWITCH markets) as opposed to direct utility partnerships