Plug-in solar comes with two different numbers, and they trip a lot of people up. One is in the law. One is in the technical spec. Here's what each one limits, and what it means for your home.
What does the law actually cap?
The law defines a plug-in microgenerator as one with a maximum rated AC output of no more than 800 watts. That's the legal ceiling on the device itself. It's also what makes the device eligible to use a specially approved plug.
What does the product spec cap?
The spec goes further. It limits apparent power to 800 VA, a slightly different measure than the 800 watts in the law. It also caps the current sent into your home at 3.5 amps. Every compliant product must carry a label stating this: a maximum of one 800 VA inverter per household circuit.
One per circuit, or one per household?
This is where it gets confusing. The spec itself says one device per final ring circuit. But it adds a caveat: GB network connection rules also apply. As of publication, Engineering Recommendation G98 Issue 2 Amendment 1 2026 limits this to one device per household. That limit applies unless and until G98 is amended. So the spec's own rule is looser than what applies today.
So how many can I actually have?
One. That's the honest, practical answer right now, for the whole household, not per circuit or per room. Whether G98 will later change to allow one per circuit is an open question, with no announced date. Until it does, plan for a single device.
The quick version
- The law's ceiling is 800 watts AC output.
- The spec's ceiling is 800 VA and 3.5 amps.
- Today's real limit is one device per household, not per circuit.