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Q Is it time to go solar?

GEORGIA CRUMB, HOVE

A Recouping the cost of solar installation is going to happen far more quickly today than it might have done a few years ago, and GaGu can’t see that changing any time soon. If you have the roof for it, it’s time.

Of course, your specifics are going to be, er, specific, so let’s be broad. The average installation cost is around £4,800 for a system which generates around 3.5 kilowatts at peak – that’s cheaper than it was, and panel efficiency is slowly creeping up; look for 20% efficiency if you can afford it.

Depending on weather, direction, and whatever fresh hell the energy companies have unleashed on us at press time, it’ll cook up an average of £270 worth of power per year, or over £400 at max. You’ll save the most on grid energy if you’re at home using it during the day.

Tesla’s Powerwall battery can hold 13.5kWh of solar juice, but at £9,379 it costs twice as much as a set of solar panels on its own.

Worried about transforming your house into something which looks like a gigantic 1980s calculator? Consider PV Slate

Although you no longer get paid for generating solar energy and using it for yourself, you can export any energy you don’t consume to the national grid for a little kickback.