

I assume you’re in the UK (who else has “allotments”) and I assume I’m from the US (planers and jointers?). That’ll matter when talking about the power grid; The US and UK grids, and appliances that plug into them, are engineered differently.
So to keep confusion down, I’m going to call Jackery-type devices “power stations” and the lithium power packs you plug into power tools “drill batteries.”
The power station I have is an Anker-Solix C2000 Gen 2, it has a 2048 watt-hour battery and an inverter that will sustain 2400 watts and peak to 4800. It’ll not only run, but START, my 13 inch DeWalt thickness planer, and it’ll take 800 watts of solar DC in. It cost $900 plus a few hundred in solar power and I’m not even maxxed out on it.
If you want a little unit you can install on your shed with a solar panel on the roof to just recharge the occasional drill battery, that’s WAY overkill. You probably don’t even need one that can deliver full standard wall socket power. A typical American wall outlet puts out 1800 watts, my drill battery charger uses a small fraction of that. I bet you could get away with a power station in the 300-500 watt range with a 50-100 watt solar panel. I would double check by putting a meter on your tool battery charger to see how much power they take. Do they make Kill-A-Watts in fish-and-chips flavor or only cheeseburger flavor?


Oh you want to go with CORDED tools. There I couldn’t give you direct guidance because the difference in voltage/current standards, I don’t know what kind of amperage or wattage your collection of tools would require, especially since you haven’t bought them yet.
I don’t have the problem you’re facing though with non-standard batteries; I have a pretty large collection of cordless tools that all take the same batteries. From a chainsaw and lawnmower to a miter saw and palm router. I’ve got like 10 of the batteries in various sizes and about 20 tools. The weirdest one in my collection is a drill battery powered soldering iron.