The best EV for powering your home during a blackout is one with a large battery, full V2H (vehicle-to-home) bidirectional capability, and a compatible bidirectional home charger installed with islanding. In the UK in 2026, the Kia EV9 leads on outright capacity, while the Hyundai IONIQ 5 offers the best balance of battery size, V2H capability, and value. For drivers without bidirectional home charging, V2L (Vehicle-to-Load) allows you to power essential devices directly from the car without any home installation.
This guide explains what you actually need for home backup power from your EV, which cars do the job best, and what limitations to be aware of before you invest.
Can Your EV Really Power Your Home?
Yes — with the right car, the right charger, and the right home setup. But there are three layers to understand:
V2L (Vehicle-to-Load): The simplest option. A socket built into the car (or accessed via an adapter at the charge port) powers devices directly — kettles, phone chargers, laptops, a small fridge. No home installation needed. Works during a power cut because the car is the source. Output is typically 2.3 kW to 3.6 kW, which limits which appliances you can run simultaneously.
V2H (Vehicle-to-Home): A bidirectional home charger sends power from your EV battery into your home’s consumer unit. This can power your whole house — lights, heating, fridge, sockets — not just individual devices. During a blackout, it requires an islanding configuration: the charger must detect the grid has failed, disconnect from it, and switch to powering your home independently. This prevents dangerous back-feeding onto the grid.
V2G (Vehicle-to-Grid): Sends energy back to the public electricity network. Standard V2G setups are grid-tied and shut down automatically during a power cut — they do not provide blackout protection. If your priority is backup power, V2H with islanding is what you need, not V2G.
How Long Can an EV Power Your Home?
An average UK home uses approximately 8 to 10 kWh of electricity per day. The larger your EV battery and the more carefully you manage consumption during a power cut, the longer you can last.
| EV Battery | Average Daily Home Use (10 kWh) | Low Use (5 kWh/day) |
|---|---|---|
| 20 kWh (Outlander PHEV) | ~2 days | ~4 days |
| 39 kWh (Nissan Leaf) | ~3.9 days | ~7.8 days |
| 60 kWh (BYD Dolphin) | ~6 days | ~12 days |
| 77 kWh (IONIQ 5 LR) | ~7.7 days | ~15+ days |
| 99.8 kWh (Kia EV9) | ~9.8 days | ~19+ days |
These are theoretical maximums. In practice, you would not discharge the battery to zero — both to preserve battery health and to keep enough charge to drive if needed. A working assumption is 60% to 70% of the battery capacity available for home power.
Best EVs for Powering Your Home During a Blackout
1. Kia EV9 — Best for Maximum Backup Capacity
The Kia EV9 has the largest battery of any V2H-capable car available in the UK at 99.8 kWh usable. Even drawing down to 20% state of charge, that leaves nearly 80 kWh available — enough to power an average home for eight days without conservation measures.
The EV9 supports V2L, V2H, and V2G via CCS. It is the most comprehensive bidirectional vehicle on sale in the UK.
- Battery: 99.8 kWh usable
- V2L: Yes (built-in socket)
- V2H: Yes, via compatible bidirectional home charger
- Protocol: CCS (ISO 15118-20)
- Price from: Approximately £65,000
Best for: Buyers who prioritise maximum backup power and have the budget for a premium family SUV.
2. Hyundai IONIQ 5 (Long Range) — Best All-Round V2H Vehicle
The IONIQ 5 Long Range’s 77.4 kWh battery gives you up to seven days of average home power (or longer with careful management) via V2H. It also has V2L built in at 3.6 kW — so even without a bidirectional home charger, you can run essential devices directly from the car. Its 800-volt architecture means fast public charging when you need to top up quickly after a blackout.
- Battery: 77.4 kWh usable (Long Range)
- V2L: Built-in, up to 3.6 kW
- V2H: Yes, via compatible bidirectional home charger
- Protocol: CCS (ISO 15118-20)
- Price from: Approximately £42,000
Best for: Buyers who want strong backup power combined with V2L flexibility, at a lower price than the EV9.
3. Renault 5 E-Tech (52 kWh) — Best Affordable V2H Option
The Renault 5 E-Tech is the most affordable car in the UK with factory-fitted AC bidirectional charging at up to 11 kW. Its 52 kWh battery gives you roughly five days of average home use, or longer with moderate consumption. At around £26,995, it makes V2H home backup accessible at a significantly lower price than Korean alternatives.
- Battery: 52 kWh
- V2H: AC bidirectional, up to 11 kW
- Protocol: CCS (ISO 15118-20)
- Price from: Approximately £26,995
Best for: Budget-conscious buyers who want genuine V2H home backup capability without premium EV pricing.
4. Nissan Leaf (3rd Generation) — Best Legacy V2H Option
The Leaf has the longest V2H track record of any car in the UK, having supported bidirectional charging since 2018. The 59 kWh Long Range version provides nearly six days of average home power. The 39 kWh version is more modest at around four days. Both use CHAdeMO for V2H, requiring the Wallbox Quasar v1 or Quasar 2 — which adds significantly to the system cost.
- Battery: 39 kWh or 59 kWh (Long Range)
- V2H: CHAdeMO bidirectional; CCS AC from 2026
- Protocol: CHAdeMO (current)
- Price from: Approximately £32,249
Best for: Existing Leaf owners with a Quasar charger, or buyers who specifically want a proven V2H track record.
5. VW ID.7 (77 kWh) — Best for V2H via Software Update
The ID.7 (77 kWh) gained V2H/V2G capability via Volkswagen’s Software 3.5 OTA update. As the largest-battery vehicle in the VW Group BiDi update rollout, the ID.7 offers up to seven days of average home power — similar to the IONIQ 5 Long Range but via a different vehicle category (premium saloon/estate).
- Battery: 77 kWh
- V2H: Via Software 3.5 OTA update
- Protocol: CCS (ISO 15118-20)
- Price from: Approximately £57,000
Best for: Buyers already committed to the VW ID.7 who want V2H as a bonus capability.
6. For V2L Only: Kia EV6, IONIQ 6, MG4, BYD Range
If you want to power essential devices during a blackout without a bidirectional home charger installation, V2L is the practical answer. These cars do not require any home electrical work — you simply plug an appliance into the car’s socket or charge port adapter and run it directly.
- Kia EV6: V2L at 3.6 kW
- Hyundai IONIQ 6: V2L at 3.6 kW via adapter
- MG4: V2L at 3.3 kW
- BYD Atto 3, Dolphin (standard), Seal: V2L at 2.2 to 3.3 kW
- Volvo EX30: V2L at 3.68 kW
At 3.6 kW, you can run a fridge, several lights, phone chargers, and a laptop simultaneously. You cannot run an electric oven, shower, or typical immersion heater on V2L alone. For basic resilience during a power cut, V2L is a practical and accessible option.
What You Need for V2H Home Backup
To use your EV as a home backup power source via V2H, you need:
- A compatible bidirectional EV — from the list above
- A bidirectional home charger — NexBlue Point 2, Zaptec Go 2, or Wallbox Quasar 2 depending on your car’s protocol
- An islanding-capable installation — the charger must be configured to disconnect from the grid and operate independently during a power cut. Not all installations include this by default; confirm with your installer before booking.
- A qualified installer — NICEIC or NAPIT approved, with specific experience in bidirectional and islanding installations
- No G99 DNO approval needed — V2H does not export to the grid, so grid permission is not required
Total installation cost for an AC bidirectional V2H system (charger + installation): approximately £930 to £1,500. This is significantly lower than the full V2G setup cost once you include the Wallbox Quasar 2 hardware for CHAdeMO vehicles.
Limitations to Know Before You Invest
Standard V2G installations do not work during a power cut. Grid-tied systems shut down automatically when the grid fails, for safety. Only an islanding V2H configuration provides genuine blackout protection.
You cannot drive while powering your home. The car must be plugged in and stationary. Plan your backup power strategy so you always have enough charge to evacuate if needed.
Battery health. Regularly discharging to low state-of-charge for home backup may cause faster battery degradation than normal charging cycles. Managing discharge depth (keeping above 20%) is recommended to extend battery life.
Planning requirements. Some islanding V2H installations require notification to your DNO, even though G99 approval is not needed for home-only use. Your installer should advise.
For the full picture on V2H vs V2G and which technology suits your situation best, see our V2H vs V2G guide. For all V2H-compatible cars and their full specs, see our V2H compatible cars guide.
Key Takeaways
- The Kia EV9 (99.8 kWh) has the largest backup power capacity of any V2H-compatible car in the UK
- The Hyundai IONIQ 5 Long Range offers the best balance of backup capacity, V2L versatility, and price
- The Renault 5 E-Tech is the most affordable V2H-capable car in the UK from approximately £26,995
- V2L is available on many more cars and provides useful emergency power for devices without a home installation
- Standard V2G setups shut down during power cuts — only islanding V2H configurations provide true blackout protection
- A V2H system (AC charger + installation) costs approximately £930 to £1,500
Frequently Asked Questions
Does V2H work during a power cut without any special setup? Not automatically. A standard bidirectional charger that is grid-tied will shut down when the grid fails, for safety. To use your EV battery during a blackout, the charger must be configured for islanding mode — disconnecting from the grid and operating independently. Confirm this with your installer before booking.
How long can a Hyundai IONIQ 5 power my home? The 77.4 kWh Long Range IONIQ 5 could theoretically power an average UK home (10 kWh/day) for over seven days. In practice, allow for a realistic discharge depth of 60% to 70% of usable capacity — approximately 46 to 54 kWh — which gives around four to five days of typical home consumption.
Can V2L power a fridge during a blackout? Yes. A modern fridge typically draws 100 to 300 W — well within the 3.6 kW output of most V2L systems. You can run a fridge, lights, phone chargers, and a laptop simultaneously on V2L. High-draw appliances like electric ovens, showers, and heat pumps require V2H with a full bidirectional home installation.
Do I need planning permission to install a V2H system? In most cases, no. Domestic EV charger installation is permitted development in the UK. However, an islanding V2H installation is more complex than a standard charger, and your installer should check whether any notification to your DNO is required. This is not the same as G99 approval (which is for grid export).
Is the BYD Dolphin good for home backup? The standard BYD Dolphin is V2L only and cannot provide whole-home backup. The BYD Dolphin V2G variant — available via the Octopus Power Pack bundle — does support bidirectional home charging, with a 60.4 kWh battery that could power an average home for around six days at typical consumption.
Useful Resources
Can Your EV Power Your Home? UK Guide — Upvolt Energy