My EcoFlow inverter arrived last week. I had it unboxed, the panels on the lawn pointing roughly south, and the app showing live generation within about an hour of opening the box. Before I had even figured out where I wanted to permanently mount everything, it had already generated over 10 kWh. That is around £2.77 at the current rate, from a system that cost a fraction of what a traditional installation would have set me back.
I am still trying to find someone to come and physically mount the panels for me. Not wire anything, not touch the consumer unit. Just fix some brackets and lift two panels onto a fence. Three companies contacted. Two never replied. One said the job was too small.
If that sounds familiar, read on.
What a traditional solar installation costs in 2026
The average MCS-registered residential solar installation in the UK costs £8,677 in 2026, according to the latest MCS Dashboard data. A smaller 3kW system starts around £5,500. A 4kW system, the standard recommendation for a three-bedroom house, typically comes in between £6,500 and £8,500. Add a battery and you are looking at £10,000 to £14,000.
Of that total, roughly 45% is hardware. About 30% is labour. The remaining 25% is scaffolding, DNO paperwork, MCS certification, and administration. On a standard install, labour runs to around £300 per installer per day, and most jobs use two people.
Payback on a traditional system is typically quoted at 6 to 10 years, though some estimates put it closer to 10 to 15 once you factor in actual usage patterns, what you export versus what you use, and whether electricity prices stay where they are or keep climbing.
None of this is a criticism of the industry. A proper rooftop installation is a significant piece of electrical and structural work. The costs are what they are. But plug-in solar is a fundamentally different proposition, and the maths looks completely different.
What a plug-in solar system actually costs
A two-panel 800W plug-in system, panels and inverter included, costs between £400 and £700 depending on where you buy and which inverter you choose. The EcoFlow STREAM microinverter, Hoymiles HMS-800, and APsystems EZ1-M all sit in a similar price bracket. Panels from City Plumbing, JA Solar, or DMEGC in the 450 to 500W range typically cost £80 to £130 each.
The electrical connection to the house, a fused spur on a dedicated circuit done correctly by a CPS-registered electrician, adds £250 to £450. There is no scaffolding, no MCS certification, no multi-day installation. G98 notification to your DNO is a free online form.
All in, a properly installed 800W plug-in system costs around £700 to £1,100. Against a traditional 4kW system at £7,500, you are spending roughly one tenth of the money.
The payback comparison
A well-positioned 800W system in central England generates around 550 to 650 kWh per year. At the current Ofgem price cap rate of 27.69p per kWh, that is worth £152 to £180 in reduced bills annually, assuming you are consuming most of what you generate rather than exporting it.
On a £900 installed system saving £165 per year, payback is roughly five and a half years. On a traditional £7,500 system saving £600 per year, payback is around twelve and a half years. The plug-in system pays for itself more than twice as fast.
If electricity prices keep rising, which the structural evidence strongly suggests they will, both figures improve. But they improve proportionally more for the cheaper system, where the upfront investment is already small.
After payback, the remaining life of the panels, typically 25 years on a quality product, is free electricity. A plug-in system that pays back in five years has twenty years of free generation ahead of it. A traditional system that pays back in twelve has thirteen.
The installer problem nobody talks about
The solar installation industry is structured around large jobs. A two-panel fence mount or a single microinverter connection is not interesting to most MCS-certified companies. The margins are too thin, the admin overhead is the same as a full rooftop job, and the scheduling is awkward when they could be fitting a ten-panel system instead.
This is not a new problem. It is why the German plug-in solar market grew the way it did, because homeowners got tired of waiting for installers to return calls and started doing it themselves. Germany now has over a million plug-in systems running. The UK is at the beginning of the same curve.
The physical installation of a two-panel plug-in system, positioning the mounting hardware, fixing to a fence post or wall bracket, connecting the MC4 cables to the microinverter, is within the capability of anyone reasonably comfortable with basic DIY. It does not require trade skills. It requires a drill, a spirit level, and the willingness to read the instructions.
What does require a qualified person is the electrical connection from the microinverter’s AC output to your house. That part, and only that part, needs a CPS-registered electrician. Finding one willing to do just that one job, without insisting on managing everything else, is a separate challenge.
My current approach: keep looking. There are independent electricians happy to do a single fused spur connection for a flat callout rate. They are not the companies that appear first on a Google search for solar installation. They are local sparks who understand the job and do not need to mark up panels and scaffolding to make the visit worthwhile. Ask on local Facebook groups, try Checkatrade filtering specifically for electricians rather than solar installers, and be upfront in the first message that the electrical work is already defined and straightforward.
What I have learned from 10 kWh on the lawn
Running the panels on the lawn before permanent mounting is not just a test. It is genuinely useful data. I can see exactly how the system performs at different times of day, identify any shading issues before I commit to a mounting position, and confirm the app is reading correctly before anything is fixed permanently.
A few things stood out. Output dropped noticeably when the panels were flat versus propped at an angle. Even a rough 30-degree tilt using a garden chair made a visible difference in the app figures. The inverter stayed cool in the shade of the fence, which confirmed where I want it permanently mounted. And the whole setup was genuinely straightforward. No special tools, no cryptic wiring, nothing beyond reading the quick-start guide.
The panels will be on the fence permanently once I have someone to fit the brackets. Until then they are on the lawn making electricity, and the payback clock has already started.
Is plug-in solar right for you?
If you own your home, have a south-facing fence, wall or outbuilding roof, and can accept a modest upfront cost, the maths is straightforward. Payback is faster than a traditional system, installation complexity is dramatically lower, and the dependency on companies that may or may not return your calls is minimal.
If you rent, the picture is also improving. BS 7671 Amendment 4, which came into force in April 2026, created the first legal framework for plug-in solar in UK homes. Once the BSI product standard publishes in July, smaller systems may not require an electrician at all for the connection.
The technology has caught up. The regulations are catching up. The one thing still lagging is the installation industry’s appetite for small jobs. But that is increasingly the homeowner’s problem to solve by not needing them.
Further reading
- Savings Calculator — work out your specific payback period
- Getting Started Guide — choosing and positioning your first system
- Rules and Regulations — G98, BS 7671 and what the BSI standard means for self-install
- EcoFlow STREAM FAQ — everything about the system I am running
- Plug-In Solar for Sheds and Garages — if a fence is not your best option
- Why Am I Not Getting the Power I Expected? — useful once your system is running
- Best Plug-In Solar Kits UK 2026 — what to buy right now