Glossary
DNO
Distribution Network Operator: the company that runs the local electricity network in your area. You must tell it about your plug-in solar kit.
A Distribution Network Operator (DNO) owns and runs the wires, substations and cables that carry electricity from the national grid to homes in its area. It is not your energy supplier: you choose your supplier, but your DNO depends on where you live. Operators include UK Power Networks, National Grid Electricity Distribution, SP Energy Networks and Electricity North West (Ofgem regional lookup).
For plug-in solar, the DNO is who you notify. G98, as amended for plug-in kits, requires customers to tell their DNO when they install or remove a plug-in micro-generator (Ofgem). This rests on the wider legal duty to advise the distributor about generators that run in parallel with the network (ESQCR reg 22(2)).
You don’t need to work out which DNO you’re in before registering. At least one DNO, Electricity North West, points people to myplugin.solar as the route to register (ENWL). We haven’t been able to confirm who operates that site or exactly how it works.