Bundle vs build your own

Across the 14 compliant kits whose inverter we can also find on its own, that inverter is about 17% of the kit price. The rest, a median of 74p per Wp, pays for the panels, mounting, cables and plug. If you can buy panels and a mount for less than that, building your own costs less, but it won’t be a compliant plug-in kit.

Not as plug-in solar. Each entry on the ENA register covers a whole kit configuration, not just the inverter, so a microinverter and panels bought separately aren’t a compliant plug-in kit however they’re put together. To connect them you’d need an electrician to install them as a fixed system.

The cheapest in stock today is the Hoymiles HiFlow HF-800-WB Microinverter at £118.80 from Electricals Online. Most kits we track use an 800 W microinverter from APsystems, Hoymiles or EcoFlow.

The Thunder Bolt Plus 460W Kit with Battery costs £1,549.99; the Thunder Bolt 460W Plug-In Solar Kit plus the Thunder Vault 1.92 kWh Plug-In Home Battery costs £1,599.97, so the bundle saves £49.98. The Thunder Bolt Plus 920W Kit with Battery costs £1,749.99; the Thunder Bolt 920W Plug-In Solar Kit plus the Thunder Vault 1.92 kWh Plug-In Home Battery costs £1,799.98, so the bundle saves £49.99. Kits with a built-in battery fall outside the plug-in rules and need an electrician either way.

We don’t list standalone solar panels yet, only kits, inverters and batteries. So we show what the panels effectively cost inside each kit, and you can enter a price you’ve found to finish the comparison.

We read the inverter model from the kit maker’s spec sheet and look for a standalone product with the same model code, such as EZ1-M or HMS-800-2WB. If we can’t find one, we say so rather than guessing, and you can pick any in-stock microinverter to compare with instead.