The wiring regulations for plug-in solar in the UK were updated on 15 April 2026 through BS 7671 Amendment 4. That dealt with the installation side: how the system connects to a home’s circuits and what the output limits are. What it did not do is define exactly what a plug-in solar product needs to look like to be certified for UK use. That is what the BSI product standard, expected around July 2026, will establish.
What the product standard will do
The BSI standard will create a specific set of requirements that manufacturers must meet for their kits to be certified as compliant with UK plug-in solar regulations. This covers the microinverter’s electrical specifications, the safety requirements for connecting to a standard UK socket, testing procedures and labelling requirements. Once it is published, a product certified to this standard can be sold as legally suitable for DIY self-installation in UK homes.
Until the standard is published, kits can be sold and used, but the fully compliant self-install route requires a CPS-registered electrician to make the final connection. The July standard is what unlocks fully legal DIY installation for the average buyer.
Why it matters for retailers
Lidl, Amazon and Iceland have all indicated they will stock plug-in solar kits, but they cannot market them as fully certified UK plug-and-play products until the BSI standard is in place. This is why the July date is so significant for the retail rollout. Once certified products are on shelves and being bought by people who have never previously considered solar, the market dynamic changes substantially.
What happens to kits bought before July
Kits purchased now from reputable suppliers like EcoFlow are not going to become non-compliant when the BSI standard publishes. The standard defines what new certified products look like going forward. If you have already bought a kit with CE and UKCA-marked components and followed the G98 notification process, you are in a sensible position. The main change will be that after July, there will be a broader range of fully certified products to choose from at competitive retail prices.
What to watch for
When the BSI standard is published, look for kits that explicitly carry certification to the new standard. In the first months after publication, not all products on sale will have been certified yet. Check for the BSI mark and confirm the product documentation references the specific standard number. Lidl’s launch timing will depend on having BSI-certified stock ready, so their shelf date is likely to follow the standard publication by a few weeks at minimum.
The October 2026 date is also worth noting: that is when the transition period under BS 7671 Amendment 4 ends. After October, the full requirements of the updated wiring regulations apply without the transitional provisions that have allowed some flexibility during the initial rollout phase.