Have a 5L white plastic barrel with a tap which was probably designed for camping or similar situations without running water. Quite handy stuff. Now I got a 5L beer keg and started to toy with the idea to use that for heating water for washing dishes or some such as we have an electric boiler in the kitchen and it really makes difference in the bill if it is turned on or not. But warming water with gas doesn't seem like too good trade and I could use a pot instead a frikin keg. And the keg's tap is plastic anyway I can't just put it over the fire.
So my idea is that make use of that green energy and move into the 21st century. I'm planning to make a "sunny cooker" (here: https://sunnycooker.webs.com/ ) in combination with the keg which should be painted matte black to maximize heat intake. There are places in the house where I could place it for a couple of hours even in winter on sunny days, and it could work several times a day in the summer if it's not raining. During warmer months it might be possible to bring it to boiling point, I think the plastic/rubber parts could take that much heat.
I have cardboard, I need foil and paint (this one is bout 10€), and maybe a new brush. I think the thing could save the expenses back less than a year, depending on the weather ofc.

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