Plug-in solar could save households money – but experts have warned of 'serious risks' (aff)

As the UK government rolls out a consultation on the idea of allowing households to use plug-in solar systems to save money on their electricity bills, electrical safety and industry bodies have warned of a "serious risk" to homes.

Energy secretary Ed Miliband said back in March that he wanted to see affordable "balcony solar" systems on the shelves in the summer, addressing the fact that nearly homes in Europe had already the technology.

By buying solar panels and a microinverter, it is possible to send the free solar energy straight into a household wiring system through a standard plug socket - but while this is commonly done in Europe, regulations prevent it being adopted in the UK.

And it's those regulations that the government is seeking to lift, as The Department for Energy Security and Net Zero launched an official consultation this week.

Ahead of the consultation, a group of leading electrical industry organisations issued a joint statement pointing out a series of potential pitfalls and hazards they want the government to take seriously.

The Electrical Contractors’ Association (ECA), Electrical Safety First (ESF), the Institution of Engineering and Technology (IET), NICEIC and SELECT, some of which represent the financial interests of electrical contractors, listed six public safety issues in their statement.

Introducing the statement, the NICEIC's technical team wrote: "Public safety must be the first principle in any rollout of plug-in solar PV units. Whilst we support wider access to cheap and clean energy, these products should only enter the mass market once the necessary regulatory, technical and product safety framework is fully in place.

“Without that foundation, there is a serious risk of avoidable hazards in homes, uncertainty for the electricity system, and lasting damage to public confidence in the energy transition.

"We believe there are serious issues that must be addressed before any mass-market adoption. We are urging Government to proceed with caution and ensure that safety, product assurance, competence and system resilience are designed into any rollout from the outset."

The team added that plug-in solar could create safety risks when connected to older or poorly maintained wiring that was never designed to accept power flowing back into the circuit, potentially affecting protective devices and increasing the risk of fire.

However proponents of plug-in solar argue that plug-in solar is restricted to 800 watts, or around three amps, while many homes now have electric vehicle chargers, installed under the watch of the industry bodies, which run at around 7,000 watts, or 32 amps.

The systems that will be used for plug-in solar power, if it is finally adopted in the UK, are already on sale, but they are supplied with bare wires that need to be linked to the household mains by an electrician.

Some users have bypassed the regulations and used a plug socket, and it has been argued that, if the practise was to be officially allowed it could be controlled more effectively.

A basic solar panel and microinverter setup can be bought for as little as £299 on eBay, and more powerful setups with batteries to store excess power can start from around £1,000.

The government hopes to see supermarkets stocking plug-in solar panels in the future, hinting that a setup could cost around £400. Lidl and Sainsbury's are among the retailers rumoured to be in talks.

Even a small solar system can save a household as much as 60p per day, with bigger plug-in systems earning back around £2 or more.

However, until the regulators and the government can agree on a pathway to allowing all homes to have an opportunity to buy into the technology it will remain a niche innovation enjoyed by only a few.

And with the summer solstice now days away, and the nights drawing in from next week onwards, any positive steps forward could be too late to make the most of the longer day lengths.

The sun is quite literally starting to set on Ed Miliband’s dreams of a nation of self-sufficient homes becoming a reality in 2026.

The five electrical industry organisations highlighted six main areas of concern in their joint statement. They are as follows.

1. Bi-directional power flow: Plug-in solar sends electricity back into a home’s wiring rather than simply drawing power like a normal appliance. They warned this could affect the operation of RCDs and other protective devices in some circumstances.
2. Fire risk in older homes: Much of the UK’s housing stock has ageing or deteriorating wiring that may not be suitable for additional power generation. Multiple plug-in units could increase the risk of cables overheating.
3. Unclear product standards: The groups fear products could reach consumers before robust UK safety standards and enforcement are established, including systems supplied with flattened cables or other accessories that may be vulnerable to damage.
4. Pressure on local electricity networks: If large numbers of households begin generating power without notifying their Distribution Network Operator, network operators may have less visibility over local supply, capacity and resilience.
5. Insurance and liability: Questions remain over whether insurers would cover a fire or electrical fault involving a self-installed system that had not been declared or was connected to unsuitable wiring.
6. Daisy-chaining and poor installation: The use of extension leads, adaptors or several devices on one circuit could increase the risk of overheating, fire and trailing-cable hazards. The groups also questioned how quickly multiple units would shut down during a power cut.