Screwfix sells one plug-in solar kit, the PowerXpress. It is easy to buy, and a bracket comes in the box. Here are the sums, and the catch with the guarantee. We have not tested it.
What do you get in the box?
Two 460 W bifacial panels, which catch light on both sides, and an 800 W micro-inverter. That makes 920 W of panels. An adjustable bracket for a wall, floor or balcony is included. The Screwfix code is 396MG. The listing says registration is required. Delivery is mainland Great Britain only.
How much does it cost?
£669 at Screwfix, price checked 12 October 2026, including 20% VAT. PowerXpress's own direct price is reported at £599, but we couldn't verify that. If it is true, it would be £70 cheaper than Screwfix. Check the maker's own page before you buy.
How much will it save a year?
The government's figure for 800 W of panels is about £70 to £110 a year. This kit has 920 W of panels but the inverter caps output at 800 W. So we use the full £70 to £110. That is our estimate, and it assumes someone is home in the daytime. A tilted south-facing panel gets the top end. A flat east or west wall gets the bottom.
How long does it take to pay for itself?
Price divided by saving. £669 ÷ £110 = 6.1, and £669 ÷ £70 = 9.6. To the nearest half year, that is 6 to 9.5 years. Our worth-it guide shows the same sum for other prices. Compare City Plumbing's 950 W kit at £456, which pays back in 4 to 6.5 years. See that guide.
Is it on the ENA register?
The Screwfix listing shows no ENA reference. It says registration is required and that it is a grid-tied system. It does not mention the ENA or your network operator. Search the ENA register for this exact kit before you buy. Then notify your network operator; see our notification guide. Don't take a third-party tracker's reference as proof.
Where can you put it?
The bracket suits a wall, a floor or a balcony. That is useful if you live in a flat, but check the rules for your building first. See flats and balconies. Two 460 W panels are big. Measure the space and the weight before you order.
Does the warranty outlast the payback?
No. The listing gives a 1-year manufacturer guarantee. The payback is 6 to 9.5 years. That fails our warranty test by a wide margin. If the kit fails in year two, you could pay again with little saved. Ask Screwfix what happens after the first year before you buy.
Who is it for, and who should skip it?
It suits someone who wants a kit today from a shop they know, with a bracket included. Skip it if you care about warranty cover. City Plumbing, Perlight and UKSOL all list 10 years. Skip it too if you can wait, because City Plumbing's two-panel kits cost £456 to £480 and have 10 years guaranteed. Check whether City Plumbing's kit includes a mount, then do the sum for both.
The quick version
- £669 at Screwfix for two 460 W panels, VAT included, checked 12 October 2026.
- Payback is about 6 to 9.5 years, by our estimate.
- A 1-year guarantee fails the warranty test, and the listing shows no ENA reference.