Study: EVs with V2H cut household electricity costs and curb need for big home batteries

Quick take

It has been reported that a new Australian study by researchers at Flinders University, Adelaide University and Murdoch University finds electric vehicles with vehicle‑to‑home (V2H) capability can substantially lower household electricity bills and reduce the need for large, expensive home batteries. The research treats an EV as a mobile energy store and shows households can draw on car‑stored energy during peak‑price periods, slashing grid imports and improving solar self‑consumption. Lead researcher Golsa Azarbakhsh said the work highlights the growing role EVs play beyond transport — a neat bit of multitasking at a time when every kilowatt counts.

The numbers

The team modelled three configurations: solar + battery + EV with V2H; solar + EV; and EV only. Under the most efficient mix — a 7 kW rooftop solar array paired with a 9 kW home battery and V2H — the study reports an annual electricity cost of $2,451, an effective electricity price of 27¢/kWh, and a 78% drop in grid imports versus a home with no solar or battery. Remove V2H and the house needs a larger 13 kWh battery to reach similar performance, with annual costs rising about 10.8%. The authors also say V2H can cut household bills by roughly 6.8% and that benefits persist under realistic assumptions about arrival/departure times, charge levels, Adelaide weather data and South Australia’s 1.5 kW solar export limit.

Why it matters

So what’s the big deal? For households already buying into rooftop solar, V2H looks like a way to squeeze more value from panels and cars without necessarily buying a second, costly battery bank — two birds with one stone for people trying to tame rising energy bills. It has been reported that the study’s models show stronger gains in winter, when solar is weaker but demand can still spike. The team presented their findings at AUPEC; the full paper is listed under DOI 10.1109/AUPEC66173/2025. Future work, they say, should look at workplace and public charging and denser housing types — because if your EV can help run your home, why shouldn’t it also help run the grid?

Sources: adelaide.edu.au, Hacker News