Vehicle-to-Home and Vehicle-to-Grid: Useful, But Not Magic
Vehicle-to-Home (V2H) lets an EV's battery power your house during an outage or peak demand period. Vehicle-to-Grid (V2G) goes further — it lets the car sell energy back to the grid. Both are technically real and commercially available in Australia in limited form. Neither is currently plug-and-play. Both require specific vehicle models, expensive dedicated bidirectional chargers, professional installation, and in the V2G case, a compatible network arrangement. The technology is promising but the practical constraints are significant.
- V2H: EV battery powers selected home circuits during outage. Requires bidirectional charger + compatible vehicle. Cost: $3,000–$8,000 installed.
- V2G: EV battery sells power to the grid, earning credits. Requires bidirectional charger + vehicle + network/retailer agreement. Limited availability in Australia currently.
- Compatible vehicles in Australia (as at 2025): Nissan Leaf (older CHAdeMO), Mitsubishi Outlander PHEV (CHAdeMO), some Hyundai/Kia models. Most BEVs are not V2H/V2G capable.
- Both require licensed electrician installation. Neither is a DIY or plug-in solution.
Vehicle-to-Home (V2H): what it actually provides
V2H uses the EV's battery as a home battery during a grid outage. The car is connected to a bidirectional charger, which connects to the home's electrical system via a changeover switch installed by a licensed electrician.
What it can power: selected circuits connected to the backup system — typically essential circuits (lighting, appliances, modem). Not the whole home unless the system is specifically designed for that load.
EV battery as home backup:
| EV battery size | Runtime at 500W load | Runtime at 1,000W load |
|---|---|---|
| 24kWh (Nissan Leaf entry) | ~40 hours | ~20 hours |
| 40kWh (Nissan Leaf larger) | ~70 hours | ~35 hours |
| 70kWh (larger BEV if V2H capable) | ~120 hours | ~60 hours |
In theory, a large EV battery provides days of backup rather than hours. In practice, battery depth-of-discharge limits (most V2H systems draw to ~20% remaining), efficiency losses in the bidirectional conversion (~85% efficiency), and the need to have the car charged and available at home limit the real-world performance.
Vehicle-to-Grid (V2G): the commercial picture in Australia
V2G programs allow the car to discharge to the grid during peak demand periods, earning credits or payments from the grid operator or retailer.
Current status in Australia: V2G is in trial and limited commercial deployment. As at 2025, a small number of retailers and programs offer V2G-capable arrangements, primarily in specific regions. The commercial return is not yet well established at scale. This is technology to watch rather than technology to plan around for 2025 purchasing decisions.
The hardware requirement is the same as V2H — bidirectional charger installed by a licensed electrician — with the addition of a network/retailer agreement that enables grid export.
The practical constraints
Vehicle compatibility is the first barrier. Most EVs sold in Australia are not V2H/V2G capable. The CHAdeMO connector used by Nissan and Mitsubishi supports bidirectional charging; the CCS2 connector used by most European and newer Asian EVs is only beginning to support bidirectional capability in specific models and configurations. If you do not own a compatible vehicle, neither technology is available regardless of what charger you install.
Cost is the second barrier. A bidirectional charger capable of V2H or V2G costs $2,000–$5,000. Installation adds $1,000–$3,000 depending on switchboard work and circuit design. Total: $3,000–$8,000+, before accounting for any V2G network arrangement.
Warranty impact is the third barrier. Using the EV battery for V2H or V2G increases battery cycle count. Some manufacturers' warranties explicitly cover V2H or V2G use; others do not. Check your vehicle's warranty terms before installing a bidirectional system.
V2H is real and functional for compatible vehicles — Nissan Leaf and Mitsubishi PHEV owners can install a bidirectional charger system today for $3,000–$8,000. For other EVs, bidirectional capability is coming but not widely available. V2G commercial programs are in early deployment. Both require licensed installation and compatible hardware — they are not plug-in solutions.
Analyse your bill to understand your current energy setup before evaluating V2H or V2G as an investment.