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The Fox Report Barry Fox’s technology column Balcony solar F or years, I have been banging on about simple, low-cost solar. One or two panels stood or hung in the garden or over a balcony, plugged into an inverter that converts 20V DC to 230V AC and pushes it into the house mains via an existing standard mains socket. No official permissions or paperwork and a free few hundred watts that – while the sun shines – cover the house ‘base load’ continually drawn by a fridge, computer or TV on standby. Of course, it isn’t that simple. The inverter has to synchronise its frequency with the mains and not upset any circuit breakers. If the inverter is feeding 230V through a three-pin mains plug, it has to disconnect within milliseconds of unplugging from the mains socket to avoid becoming a shock hazard. Technically, this is no longer difficult. ‘Balcony solar’ is now big in Germany and other continental countries, where safe plug-andpush power kits are on sale. Hang the panel(s) over a balcony, plug a couple of DC leads into a weatherproof (or internal) inverter and run a mains lead with a standard mains plug into a standard wall socket. Chinese factories are churning out push-power kits, which retailers are badging, and house-owners or renters are cash-and-carrying from a supermarket. When you move home, you just unplug and go. Better late than never, the UK government is now moving to allow similar sales in Britain. The official announcement (https://pemag.au/ link/acbz), dated 24 th of March, is long on hyperbole and enthusiastic quotes from Uncle Tom Cobley and all, but short on hard facts. I quote: ‘Plug-in’ solar panels to be in shops within months, offering households a chance to significantly cut energy bills. More households will be helped to save money on bills through plugin solar panels as the government vows to go further and faster on clean energy… … Germany is seeing around half a million new devices plugged in per year. 78 The free solar power can be used directly through a mains socket like any other device, without an installation cost, thereby reducing the amount of electricity taken from the grid and cutting energy bills. The easy-to-install technology could save many households significant amounts on their energy bills and help make the UK less reliant on global fossil fuel markets. Georgina Hall, Corporate Affairs Director at Lidl GB, is quoted as saying: At Lidl GB, we are committed to making sustainable living affordable for everyone and we welcome the government’s move to modernise regulations in the UK. Updating the regulatory landscape for this ‘plugand-play’ technology is a positive step towards empowering British households to manage their energy costs and support the nation’s netzero ambitions. As someone who bought and struggled to set up one of Lidl’s robot lawn mowers (which failed with unhelpful error messages after one season), I must admit to having some reservations here. The government says it “will work with the Energy Networks Association, DNOs and Ofgem to update the G98 distribution code and wiring regulations BS 7671 to allow UK households to connect <800W plugin solar panels to domestic mains sockets, without the need for an electrician and with tailored safety standards”. Fine words, but I suspect the government may have underestimated the mass of paperwork and official permissioning that need to be sorted. There has been – and rightly so – a jungle of restrictions on who can connect what to the national grid via domestic wiring, fusing and metering. It’s a fact of electronics that if someone can find a way to connect something incorrectly, they will. Will the 800W power ceiling apply to individual plugs or whole houses? Can separate inverters be fed into separate sockets? High-tech equipment is now sold like sweets. I recently stood behind someone in Argos who was hoping to get his crashed or infected laptop working again under guarantee. Although it is not a safety issue, how to correctly wire the low-voltage plugs and sockets from the panels can be confusing, with the negative and positive, male and female, outer casings and internal pins; it’s easy to get it wrong. The plugs won’t grip thin wire cores. So the kits sold will need to come with all plugs and wires prefitted and weatherproofed. Mains plugs will have to be prefitted to avoid incorrect Live, Neutral, Earth wiring, which could play havoc with safety circuit breakers. From equipment already listed by Amazon, the likely starting price will be around £500 for two panels and a microinverter. As an immediate, impatient experiment, I bought an inverter direct from China for a little under £50 and two 100W panels for £50 each, plus a few metres of two-core garden mains cable and a selection of connectors. The total cost was around £175. My inverter came with Chinglish instructions and a very confusing description of what its LED is trying to tell me: • • • Long bright green light: micro inverter to normal Green light flashing: micro inverter power Long bright red light: an island protection and fault Red light flashing: 1. AC voltage under-voltage protection (flash a red light) 2. AC voltage overpressure protection (red light flashing 2) 3. Frequency protection (red light flashes three times) Very likely, some badged Brit kits will come with instructions that blindly copy this or similarly garbled text. After some trial and error, I think the basics are: when the inverter LED shows steady green, it is correctly connected to a working panel and live mains; when it flashes green at regular intervals, it is receiving Practical Electronics | July | 2026 The Fox Report Barry Fox’s technology column good DC and pushing AC into the mains; when the LED turns steady red, something is wrong. My microinverter is, on paper, rated too low in wattage for the two 100W panels. In practice, it seems well able to cope, even on sunny days. To see if the panel is pushing useful power into the mains when the sun is shining and the inverter is flashing green, I checked the house smart meter while using a switch plug to connect and disconnect the inverter from the mains. It takes a while for the meter to register the change (by which time a fridge may have cut in or out), but with the sun shining, the two panels seem to be cutting consumption by around 2p per hour, so around 1p per panel. With, let’s hope, an average of 8 hours sun or bright light per day, that’s around £30 a year per panel, so £60 for a two-panel kit. Perhaps commercial kits will do better, and perhaps the price of a two-panel kit will eventually fall to £199. Even so, I suspect that many people using balcony solar will earn less than they expected. Personally, though, I am happy just to see the LED flashing green and telling me I am getting at least some free power from the sun. 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