Overview
- Retailers and specialists are selling heavily discounted PV plus battery bundles that range from standard 2,000 Wp kits up to multi‑kW arrays paired with multi‑kWh storage, reducing upfront cost per watt and per kWh.
- The regulatory line that separates simple plug‑in devices from full PV installations is commonly set at 2,000 Wp total module power and 800 VA maximum feed‑in, and systems above those limits must be treated as regular solar installations.
- Since 27 August 2026 the UK permits only government‑approved plug‑in mini‑solar devices that meet a new product specification and explicitly excludes plug‑in batteries and sets with integrated storage from sale and operation.
- Kits that exceed the plug‑in thresholds frequently need a certified electrician, a Wieland or fixed connector, and notification or registration with the network operator plus, in many cases, a bidirectional or approved meter.
- Modular storage products from Anker and EcoFlow let buyers start small and expand later, which encourages pairing large module arrays with limited base batteries and thereby blurs the practical line between plug‑and‑play 'Balkonkraftwerk' and regulated PV systems.