Home Battery Storage in Cornwall

Most home batteries carry a 10-year warranty and are rated for 4,000–10,000 charge cycles depending on the manufacturer. A daily charge and discharge cycle represents approximately 10–15 years of real-world use before capacity degrades to 70–80% of original. Tesla Powerwall and Foxstar both carry 10-year warranties with performance guarantees.

For most 3–4 bedroom homes with solar panels, a 5–10kWh battery is appropriate. A 5kWh battery covers the typical evening demand of most households; a 10kWh battery provides more flexibility and better handles high-demand households with EV charging or heat pumps. We assess your solar generation data, household demand profile, and overnight consumption pattern to recommend the right size during the survey.

Yes — all battery storage installations now qualify for 0% VAT, whether installed with new solar, retrofitted to existing solar, or even as a standalone system. This has been the case since February 2024. The 0% rate runs until March 2027, then reverts to 5%. Must be professionally installed.

Yes — we retrofit battery storage to existing solar installations routinely. Most retrofit batteries are AC-coupled (connected to the existing system on the AC side), which is compatible with any solar installation regardless of age or inverter brand. For older systems with a failing inverter, we may recommend replacing the inverter with a hybrid model with built-in battery integration.

At current electricity prices (24.67p/kWh, Ofgem Q2 2026), a correctly sized battery paired with solar panels typically pays back in 5–7 years in Cornwall. Without solar panels, battery payback via grid arbitrage (charging at 7p overnight on Octopus Go, discharging at peak rates) is longer — typically 8–12 years. Adding a time-of-use tariff significantly improves returns.