Plug-in solar panels
How they work, what they cost and how much you could save
Plug-in solar panels are now available in England, Wales and Scotland. They could be a simple way for some households to cut their energy bills. But the payback period could be around five to 10 years, and not all homes are suitable. Here's what you need to know about how they work and whether it's right for you.
This is the first incarnation of this guide. We'd love to know your thoughts on plug-in solar panels, or if you've any feedback or questions we've not answered. Let us know in the Plug-in solar panels forum thread.
What are plug-in solar panels?
Plug-in solar panels are portable solar panels that can be placed outdoors (such as on a balcony railing, garden fence, patio or shed roof). They're a cheaper, easy-to-install alternative to expensive rooftop solar panel systems. In theory, you simply plug them in to your mains electricity and they're ready to use. Plus, as they're portable, you can easily take them with you if you move home.
One of the key benefits of plug-in solar is that you don't need an electrician to install them (unlike rooftop systems), you can do it yourself - though do check it's safe to plug them in your home.
How do plug-in solar panels work?
Plug-in solar panels work in the same way as rooftop solar, by generating electricity from sunlight. The panels feed this electricity directly into your home's electrical circuit, via a standard three-pin wall socket.
Any appliance you have switched on will automatically and instantly use this free solar-generated power before importing costly electricity from the National Grid, which you pay your energy supplier for (do a full market comparison to make sure you're on the cheapest rate for you).
What do you get in a plug-in solar kit?
Plug-in solar systems sold under the new rules can generate a maximum of 800W of usable power, thanks to a built-in inverter limit. That's much smaller than a typical rooftop solar setup, which is usually 4kW or more. Some kits may include solar panels with a higher combined capacity than 800W, but the microinverter ensures no more than 800W is fed into your home's electrical system at any one time.
The kit will also include a microinverter, which converts the electricity produced by the solar panels into the type of power your home uses.
Some kits should also come with mounting equipment too. However, exactly what's included may vary between manufacturers, so it's worth checking what's in the box before you buy.
Are plug-in solar panels worth it?
Plug-in solar panels are now available for sale in England, Scotland and Wales. If you're interested, first consider whether the panels will generate enough savings on your electricity bill to recoup the upfront cost. As the panels have only just become available, accurate saving figures are hard to come by - but based on current info:
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You could save between £70 and £110 a year on energy bills. According to data from The Department for Energy Security & Net Zero (DESNZ), based on a typical household with an 800-watt system.
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An 800w plug-in solar panel system could cost you between £500 and £1,200. Based on prices we've seen from the handful of retailers selling them.
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That means you could break even in around 5 to 7 years. If you can get the panels for around £500. A pricier £1,200 system could increase your payback period to around 11 and 18 years.
However, your saving from the panels will depend on the size of your system, where you live, how you use your energy and the weather - see our plug-in solar need-to-knows for full info.
Warning: Before getting plug-in solar panels, it's a good idea to get your house's wiring checked to make sure it's safe to plug in the panels. We've full info below on what to check.
In Northern Ireland? You can't get plug-in solar panels yet
While new rules allowing the installation of plug-in solar panels came into force in August for England, Scotland and Wales, they don't apply to Northern Ireland.
Northern Ireland will need its own rule change, and so far it hasn't been confirmed whether this will happen
Where can I buy plug-in solar panels?
From Thursday 27 August, new rules were introduced allowing plug-in solar panels to be sold widely in England, Scotland and Wales. Only a handful of retailers are currently selling them - we've listed the ones we know about so far (let us know if you spotted them for sale anywhere else:
One solar panel | Two solar panels | |
|---|---|---|
£348 - £671 | £456 - £952 | |
- | £499 - £919 | |
£450 | £650 | |
£599 - £849 | £849 - £1,199 |
More retailers are expected to start stocking plug-in solar panels - including Currys, Aldi, Lidl, B&Q, Screwfix and Wickes. We'll update this as we hear more.
Plug-in solar panels are limited to 800w - should you pay for more?
If you're shopping for plug-in solar panels, you may notice that you can buy systems that can generate over 800w - we've seen kits that have a capacity of up to 1,260w.
However, under UK rules, plug-in solar panels are limited by the microinverter (which converts the generated direct current into usable alternating current). This limit is set by Government at 800 'volt-amps' (VA), which is commonly reported as an 800w limit.
This isn't technically the case. An 800w panel can technically generate 800VAs, but in real-world conditions solar panels generally can't consistently produce their maximum output.
So going for a higher wattage system means you may get closer to that 800VA maximum output more often than with a smaller system - but the trade-off is a higher price
You can install plug-in solar yourself - but it's not always as simple as plug and play
Unlike full conventional rooftop solar panels, one of the benefits of plug-in solar is that you don't need an electrician to install them.
While you can install them yourself, before you take the plunge, make sure you consider where you'll put them, whether it's safe to install them in your home, and whether you're comfortable putting them together and mounting them in your chosen spot.
Step 1: Check it's safe to install plug-in solar in your home
Plug-in solar panels aren’t standard appliances. While they’re marketed as ‘plug and play’, they introduce a new source of electricity into your home – which brings electrical and fire risks. So first make sure it’s safe to plug them in.
The Institution of Engineering and Technology recommends having your wiring professionally checked first. Many UK homes have ageing wiring, worn parts or DIY alterations that could make using solar panels unsafe.
You can get an Electrical Installation Condition Report (EICR) from a qualified electrician to check the health of your electrics. Do mention you’re considering plug-in solar, as this may affect any recommended updates. These reports can cost £100 to £250 according to Checkatrade, which will add to the panels’ payback time.
Step 2: Find the best place to install them
Plug-in solar panels can be installed almost anywhere they’ll fit, such as a balcony, garden fence, patio, garage roof or exterior wall.
Ideally, choose a spot that gets plenty of sunlight – somewhere south-facing and unshaded for much of the day. If possible, tilt them to about a 35-degree angle to maximise sunlight exposure.
Panels can be large, so measure carefully to check they’ll fit. Also consider where you’ll plug them in. Use a weatherproof, dust-resistant outdoor socket (trailing cables through windows or doors isn’t safe or practical). According to Checkatrade, this could cost £140 to £260 – again adding to the payback time.
Safety warning: DON'T use standard extension cables as they could become dangerously hot. Always check before buying how long a cable you need and make sure the panels you buy come with a long enough cable. There are 'MC4' extension cables available (MC4 is the standard connection for solar panels), but do make sure these are safe before using them.
Step 3: Buy your plug-in solar system and follow the manufacturer's instructions
If it’s safe, you’ve got space and an unshaded area, the next step is to buy the panels. Once you have them, you may need some DIY skills to install them. Typically, you’ll attach the panel to a mounting bracket and connect the microinverter (your system should include instructions). If mounting on a wall or balcony railing, extra steps may include securing the bracket or drilling holes.
If installing them yourself, always follow the manufacturer’s safety guidance.
Step 4: You MUST register your plug-in solar panels within 28 days
Once installed, you'll need to register them within 28 days of connecting them. You can use the UK plug-in solar registration form.
How do plug-in solar panels stack up against rooftop solar systems?
Plug-in solar panels are mainly aimed at households without space for a full conventional rooftop system. They’re relatively small and easy to install, so if you’re in a small home or live in a flat with no roof access, they can give you some solar power and help cut your electricity bill.
Even if you do have space for a full rooftop system, installation is costly – a typical 4.6kWp system costs about £7,600 to install, compared with about £500 to £1,200 for an 800w plug-in solar system. So homes of any size can benefit.
However, savings on electricity bills will be lower. Plus, while some suppliers let you export energy from plug-in solar back to the grid and get paid, any earnings from this are likely to be minimal - while for rooftop, it's a major earner.
Cost | Annual bill savings | Annual export earnings | Total annual savings | Time to break even | |
|---|---|---|---|---|---|
800w plug-in solar system(1) | £450 | £70-£110 | None | £70-£110 | 5 to 10 years |
4.5kWp Rooftop solar system (2) | £7,600 | £200-£330 | £600-£700 | £900-£930 | 9 years |
(1) Based on average potential savings from the Department of Energy Security and Net Zero, and the lowest cost we've seen for an 800w plug-in solar system. (2) Based on a 4.5kWp system installed in London. Cost, savings and export earnings figures from the Energy Saving Trust.
You CAN get paid for exporting electricity from plug-in solar panels, but you're unlikely to earn much
One of the key benefits of rooftop solar is the ability to export, and get paid for, any electricity you generate but don't use under the Smart Export Guarantee (SEG), with providers paying up to 16p for each unit of electricity you export back to the grid.
With plug-in solar panels, technically you shouldn't get paid for electricity you generate but don't use, as solar systems should be installed and certified by an accredited installer to be eligible for the SEG (which you don't need with plug-in solar). However, some providers we spoke to said they will accept plug-in solar owners on their SEG tariffs.
So far, this includes British Gas and Octopus (we're still checking with providers, and will update this if we hear more are doing it). Both offer payments of up to 12p for every unit you export if you're an existing customer or 4.1p with Octopus and 3.1p for British Gas if you're not already a customer.
However, bear in mind, with plug-in solar, you're only generating small amounts, so it's likely most of what you generate would be used up by always-on appliances like fridges and freezers, so you'll unlikely to earn huge amounts.
You can have both rooftop solar and plug-in solar
If you already have a rooftop solar, you could add plug-in panels to give you a little extra boost, though if your existing already meets most of your energy needs, it may not be worth the extra cost.
If you do choose to add plug-in, you should speak to your installer or get your system checked by a qualified electrician to make sure adding plug-in won't overload your current system.
Renting? You'll need to ask permission from your landlord
If you live in rented accommodation, you'll need permission from your landlord to install solar panels anywhere in or around your home. The Government has said it's working to ensure there is clear guidance on what tenants can and cannot do.
Quick questions
Are plug-in solar panels safe?
Yes, plug-in solar is already widely used by households across Europe.
Ensure you buy from a reputable retailer and that it meets UK product safety standards. Plug-in solar panels do have built-in safety features. Typically, the inverter will immediately shut down if it’s unplugged from the wall or if there’s a powercut. This prevents the plug pins from being ‘live’ and shocking you, as well as sending electricity back into the grid, while engineers might be working on the line.
Do make sure it's safe to plug them in to your home before you get them (see how to check) and follow all safety guidance from the manufacturer when installing them.
What happens to the electricity I generate but don't use?
Any electricity you generate with plug-in solar panels that you don't use will get sent back to the National Grid. You can't currently get paid for this - like you can with rooftop solar under the Smart Export Guarantee - scheme. That means energy you generate but don't use is essentially wasted (at least for you).
Do you need a smart meter for plug-in solar panels?
No, you won't need a smart meter to use plug-in solar panels. However, smart meters are useful as they help you accurately measure your energy use and take advantage of time-of-use tariffs.
Can you use solar panels with a battery?
Technically, yes plug-in solar systems can be used with batteries, so you can store the electricity it generates when you're not using it to use later.
However, the current UK rules don't support batteries with plug-on solar, though they could become available in future.
In Europe, you can buy all-in-one solar and battery plug-in systems, for example. These could become available in the UK at some point in the future, though we don't know when.
How long do plug-in solar panels last?
Plug-in solar panels have a similar lifespan to rooftop systems – around 20–30 years. Microinverters usually come with a 10–12 year warranty.
Regularly clean off dirt, leaves and bird droppings to maintain efficiency and lifespan.
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