Modular Solar sells single units that you can link. The sums are the slowest of the five kit families we looked at. We say so plainly, because you should know before you pay.
What do you get in the box?
There are two units: 340 W and 475 W. The seller says delivery and cables are included, and that the unit plugs into an outdoor socket. The mounting is not stated, and the inverter output is not stated either. The seller also says you can "connect two units". We have not tested it. This is what the seller says. Ask about the mount before you buy.
How much does it cost?
The 340 W unit is £465 and the 475 W unit is £650 on modular.solar. Price checked 12 October 2026. The price includes 20% VAT, because a kit you fit yourself is standard-rated. Modular Solar is also listed on Amazon UK. We could not read the Amazon price, so we cannot say it is the same. Check it on the day.
How much will it save a year?
The government says 800 W of panels saves about £70 to £110 a year. We scale it down. For the 340 W unit: 340 ÷ 800 × £70 to £110 comes to about £30 to £45 a year. For the 475 W unit: 475 ÷ 800 × £70 to £110 comes to about £40 to £65. 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. 340 W: £465 ÷ £45 = about 10.5 years, and £465 ÷ £30 = about 15.5 years. 475 W: £650 ÷ £65 = about 10 years, and £650 ÷ £40 = about 16 years. That is poor value per watt. Other kits with a single 455 to 460 W panel cost £449 to £450 and pay back in about 7 to 11 years. See is plug-in solar worth it?.
Is it on the ENA register?
The Amazon title says "fully compliant with new UK regulations". The modular.solar page shows an image that says "ENA-Type-Test-Compliant", but no register entry. These are the seller's claims, and we have not checked them. Search the exact model on the ENA register yourself before you buy. Read our certified kits guide for what to look for.
Where can you put it?
The seller does not say how it mounts, so we cannot say. Ask what comes in the box for a wall, a fence or the ground. The "connect two units" claim needs care. Network rules (G98) allow only one plug-in device per household, so two separately plugged-in units are not allowed. Our 800 W rule guide explains the cap. Ask the seller whether 'connect two units' means one device on the register.
Does the warranty outlast the payback?
The seller lists a 10-year warranty. Our rule is that the warranty should be longer than the payback. The payback here is 10 to 16 years. So the warranty ends before the kit has paid you back in most cases. That is a bad sign. You are likely to pay for the unit and not get all of it back inside the warranty.
Who is it for, and who should skip it?
It might suit someone who wants a small unit and plans to add a second one later, if the seller can show that is allowed. Most people should skip it. The 340 W unit costs more than a 455 W panel from other sellers. The 475 W unit costs £200 more than they do for little extra power. Buy it only if you cannot get another kit.
The quick version
- The 340 W unit is £465 and the 475 W unit is £650, with 10-year warranties.
- We estimate payback at 10.5 to 15.5 years and 10 to 16 years. Poor value per watt.
- Ask how the "connect two units" claim fits the rules before you buy a second.