Ok so the shed has no power and its a rented property so I cant start drilling holes and tinkering with electrics. What I really want is some form of lighting where it uses a replaceable battery pack, like you find in cordless tools so that you can have a fully charged battery on standby and then switch it over when the one in the light has run out of juice and take the dead one in and charge it up ready for the next switch over. I've been looking around but cant really find what I want, maybe because I'm googling using the wrong terminology.
I have one of these, its actually rather bright, its not quite what you asked for but you can run it using a USB power pack, or its own internal battery https://www.amazon.co.uk/gp/product/B07QN6GDRL/ref=ppx_yo_dt_b_asin_title_o04_s01?ie=UTF8&th=1
How long does it last when switched on, it states 80 hours. If that's the case then that would be awesome as she spends about an hour a day in her shed dealing with her guinea pigs so 80 days would be awesome.
I'm not totally sure, I would suspect 80hrs is on its lowest setting, it should be able to do ten hours on its brightest so 40 on its middle? I'm guessing I have't been able to drain its power pack fully yet, but you can run it off a USB pack while charging so it would last a lot longer in theory.
We've got this https://www.amazon.co.uk/PowerBee-Ray-Shed-Light-Superbright/dp/B002GN4WGM?ref_=fsclp_pl_dp_2 , no idea if it'll be bright enough for your purposes, and the guinea's might be big enough to turn the thing on, but that ain't not no reason why you can't look for a.n.other solar solution, such as , https://www.amazon.co.uk/Zennox-Sol...S4R5Y17MNHH&psc=1&refRID=FP10KNCEVS4R5Y17MNHH
I have something like this: https://www.canadiantire.ca/en/pdp/motomaster-eliminator-powerbox-600-0112002p.html#srp with a 2W (go 5W+ if you're in the shed a lot) solar panel to keep it topped up and then I just ran normal building wire up to the ceiling of my shed with 2x household 7W LED bulbs. It works fantastic and if you ever need to boost your car or the power goes out, you just grab it out of the shed (my problem is remembering to put it back ). Edit: Pic
We have a small toiletbuiding with no power, that's used for Events ~4-5 times a year. I've installed a few 12V LED-Spots, and power them off an old motorcycle battery which I charge on a normal car battery charger somewhere else. Convenient if you happen to have a spere (old) battery. Look for Caravan/campervan/boat 12V interior Lights. But really you could run strip Lightning too. You'll be amazed how much light comes out of just a few Watts of LED's
I use similar when camping and use in shed, I have rigged up proper 240v energy saver lighting to it that I happen to have made for lighting up my caravan awning but you could use 12v lighting and not waste power with inverter, having 240v of course allows phone and laptop charging when camping etc and can charge from lighter socket in boot of car when driving about. https://www.machinemart.co.uk/p/clarke-js5in1-5-in-1-jump-start/ Machine mart regularly has sale or VAT free, so the sort of thing to pick up then. It is pricey but has also been a boon with flat batteries on cars and motorbike etc, I just make sure I charge it every 3 months if it has had light use. Have actually used it in the house during power cut to provide TV and lighting, of course it doesn't last for ever it is only a small battery You could try solar shed lighting, plenty of options, the kits with battery and panel would provide lighting you would never need to charge. https://www.thesolarcentre.co.uk/catalog/Solar_Shed_Lights-85-1.html
If you do go solar, handy calculator, https://www.bimblesolar.com/solarcalc When mine was working (laid out on the lawn) I was able to run a small invertor to charge my drill battery, some LED lights, a phone charger and the battery was actually charging, I do have about 200W of panels and it was weirdly sunny. But still gives you an idea.
Some great ideas but some are way to pricey, she only needs it for say half an hour to feed her piggies.
Something like this? My mum uses it in her greenhouse in the evenings, plenty of light, rechargeable an drop proof https://www.amazon.co.uk/Arlec-WL0001GB-Work-Light-Black/dp/B081FN5YT3
