Solar Panels, Battery Storage & EV Charging: What to Install and When

Solar Panels First: The Foundation

Solar panels should always come first. They generate the electricity that batteries store and EV chargers use. Installing batteries or EV chargers without solar means you are still drawing from the grid at standard rates.

A standalone solar system costs £5,000–£8,000 and reduces bills by 60–80% for households that use electricity during daylight hours. If you are home during the day or run appliances on timers (dishwashers, washing machines), solar alone delivers strong returns without additional investment. Use our savings calculator to estimate what you could save with solar alone.

Adding Battery Storage: When It Makes Sense

Battery storage costs £3,000–£6,000 depending on capacity (5–10 kWh is typical). Batteries store excess daytime solar generation for use after sunset, increasing self-consumption from 40–50% to 70–85%. This matters most for households where everyone works during the day — batteries capture daytime generation for evening use.

Payback periods for batteries alone are longer: 10–15 years. But batteries also provide backup power during outages (if configured correctly) and enable participation in grid flexibility schemes that pay you for charging and discharging at specific times.

The critical VAT rule: if you install solar and battery together, both qualify for 0% VAT. If you add a battery later, you pay 20% VAT on the battery — that is £600– £1,200 extra. This is the strongest argument for bundling upfront, even if you do not urgently need storage.

EV Charging: The Final Layer

EV chargers cost £800–£1,500 installed. Smart chargers (required for grant eligibility) prioritise solar electricity when available, reducing charging costs to near-zero. Without solar, you are charging from the grid at roughly 24p/kWh. With solar, the marginal cost is zero.

EV chargers installed alongside solar panels qualify for 0% VAT. Installed separately, you pay 20% VAT. The OZEV grant (up to £350 for home chargers) ended for most homeowners in 2022, but some local authorities offer regional grants — check your council’s website.

Only install EV charging if you already own an electric vehicle or plan to buy one within two years. Charger technology and standards evolve, and installing one you will not use for five years risks obsolescence.

Bundling vs Phasing: The Trade-offs

Bundling upfront

Installing solar, battery, and EV charger together costs £10,000–£15,000 but maximises VAT savings (£2,000–£3,000) and ensures system integration. All components are designed to work together, monitoring systems unify data, and you have single-point warranty accountability.

Phasing over time

Phasing spreads costs but loses VAT advantages and risks compatibility issues. A battery added later might not integrate seamlessly with your existing inverter, requiring additional hardware. Separate installations also mean multiple roof access sessions, scaffold hire, and disruption.

The recommended middle ground

Install solar and battery together (capturing VAT savings), then add EV charging when you buy an electric vehicle. This balances upfront cost, VAT optimisation, and practical need.

Use our savings calculator to estimate your returns from solar, battery, or both. When you are ready, compare MCS-certified installers who can quote for the combination that suits your household.