According to the IET’s Mark Coles, there are not only hurdles to overcome, but problems so vast that they could potentially derail the whole concept of rechargeable solar power in the UK. Coles is the head of technical regulations for the IET and has been developing standards for more than two decades. He said it was “a surprise to hear the government’s announcement” and shared serious reservations about the implementation of the program. In fact, on the same day the government announced plans to open up rechargeable solar power, the IET issued a warning. In addition to reminding consumers that these systems are not yet legal, it encourages them to have the wiring in their home checked by a professional. “What may be safe in one home may pose a significant risk in another,” he said, “a professional check is the only way to be sure.”
For example, the UK standards for residual current devices (RCDs) were designed for one-way electrical traffic. “Think about your circuit breaker, your fuse box, you have power going in and wires going out to power your devices,” he said. When you put electricity on the final circuit, going in the opposite direction, you “can fry the device because it is not designed to receive electrical power from that side.” It was only a few years ago that the UK opened up to two-way RCDs capable of supporting two-way traffic, but even today the old hardware is still “for sale now, still being installed”. This isn’t just an inconvenience to your wiring, because if an RCD fails it could be fatal.
Coles added that while the German system was praised, it may have been launched based on decisions made decades earlier. Wiring, plugs and consumer units in Germany are bipolar, which is less secure overall than the UK version, but much easier to accept power from both ends. In comparison, “plugs and sockets in the UK are not suitable for connecting an electrical source,” Coles said. He added that the UK plug rules “make it very clear that you should not plug in a low voltage generator (which is what a rechargeable solar system is).” He also expressed concern that without a universal standard for rechargeable solar units, it would be impossible to provide certainty to regulators and consumers. And, as an added risk, insurers might not compensate in the event of a fire, because using such a system would violate rules on the safe use of sockets.
If anyone still wants to get a plug-in system, Coles advises them to have their wiring checked by a qualified electrician. And, most importantly, to prepare for the possibility that they won’t be able to use it unless they reconnect some or all of their home’s electrical systems at significant cost. “It’s not as simple as buying this device and plugging it in,” he said.
Luke Osborne, technical director at Electrical Safety First, added his concerns about the issue of new technology coming into contact with older wiring. “Rechargeable solar panels can negatively impact protective devices such as RCDs, which protect against electric shock,” he said. He also called on the Government to “clarify how it intends to address these concerns”, to ensure “the UK has the best and safest solar panel deployment in Europe”.
