Solarfy is a small seller with two kits made for gardens and flat roofs. The Duo is the cheaper way to get two panels. The page has one gap that matters, and it is the warranty.
What do you get in the box?
The Solo has one 455 W panel. The Duo has two, for 910 W in all. Both come with a ballast mount for a garden or flat roof. Ballast means you weigh the frame down with weights instead of drilling. The AC cable ends in a UK plug. The product pages we read do not state the inverter output, so ask the seller. We have not tested either kit. This is what the maker says.
How much does it cost?
The Solo is £449 and the Duo is £599. Price checked 12 October 2026. The price includes 20% VAT, because a kit you fit yourself is standard-rated. The second panel adds only £150 to the Duo. The Which? price check of 7 October 2026 put plug-in kits at about £450 to over £1,000, so both of these sit at the low end.
How much will it save a year?
The government says 800 W of panels saves about £70 to £110 a year. The Solo is 455 W, so we scale it: 455 ÷ 800 × £70 to £110 comes to about £40 to £65 a year. The Duo has 910 W of panels, but the inverter caps output at 800 VA, so it gets the full £70 to £110. These are our estimates, scaled from the government's 800 W figures. They assume someone uses power at home in the day.
How long does it take to pay for itself?
Divide the price by the saving. Solo: £449 ÷ £65 = about 7 years, and £449 ÷ £40 = about 11 years. Duo: £599 ÷ £110 = about 5.5 years, and £599 ÷ £70 = about 8.5 years. The Duo wins on value, as the second panel is cheap. See is plug-in solar worth it? for how we do the sums.
Is it on the ENA register?
Solarfy's page title says "ENA Registered". The page also says the exact kit must be listed on the ENA device register, connected as instructed and registered after installation. That is a maker's claim. We have not checked it for you. Before you buy, search the exact model on the ENA register yourself. Then notify your network operator, as the DNO guide explains.
Where can you put it?
The ballast mount is made for a garden or a flat roof. You can put the frame on a lawn, a patio or a flat garage roof, and weigh it down. That avoids drilling into a wall, which helps renters. Check the weights are heavy enough for wind, and that the roof can bear them. Our guide to sheds, fences and flat roofs covers it.
Does the warranty outlast the payback?
We cannot tell. The Solarfy pages we read do not state a warranty. Payback is 5.5 to 11 years, so you want a warranty that is longer than that. Email Solarfy and ask for the panel and inverter warranty in writing before you pay. If they cannot give you one, that is your answer. Pick another kit.
Who is it for, and who should skip it?
The Duo suits a garden or flat roof, where you can weigh the frame down, and where a low price matters. Skip it if you want a drill-and-bolt wall mount, or if you want the warranty settled on the page. The Solo is the weaker deal. At £449 for 455 W it pays back slowly compared with the Duo.
The quick version
- The Solo is £449 for 455 W. The Duo is £599 for 910 W.
- We estimate payback at about 7 to 11 years for the Solo, 5.5 to 8.5 for the Duo.
- The warranty is not stated on the page, so ask before buying.