You're right that the same criticism could and perhaps sometimes should be aimed at "net zero" homes with solar. Arguably solar is even worse than wind in the UK, because we're so far north that it has an awful capacity factor and it reliably drops off when power is needed the most. Ecohomes and net-zero homes have extra insulation that does provide a benefit in winter, but home solar alone is dubious. (The UK government also basically killed off subsidies for it.) It's a little more useful in countries closer to the equator with better capacity factors and summer aircon rather than winter heating, since output is reasonably closely correlated to demand then, but still won't get us to actual zero even there.
No it's not dubious at all. It's hilariously beneficial considering how far north we are, where I honestly thought it would be very borderline, and probably not worth it at all.
We just about eliminated the electricity component of the typical UK supply of electricity and gas for heating. That's not net zero, or creative accounting, that's actually eliminate use of grid electric for nine or ten months, with a little use in winter. That only because of switching water heating to the panels, that was previously on gas. We're in N Cumbria.
