Why not cover a 1 litre bottle in solar panels and use the electricity to cool the water using a thermoelectric module (ed. - Peltier Effect). That way, the stronger the sun, the more it cools, and no need to carry a whole cool box.
-- alistairwest, Jun 27 2005

I might have got it wrong but I was planning on using the Peltier-Effect. I thought these devices are called thermo- electric modules. And evaporating the water would involve exposing the liquid to the elements and would also have very limited value with drinks other than pure water.
-- alistairwest, Jun 27 2005


The first thing I thought of was peltiers. You should incorporate that in the idea text [+].
-- contracts, Jun 27 2005


I've got a Peltier effect fridge that runs off a car battery.
-- DenholmRicshaw, Jun 27 2005


Thanks C, it's added. DR - I was also thinking about using an existing Peltier effect fridge and powering it from a solar panel on a cord. That way you could leave the fridge under your parasol while leaving the panel in direct sunlight.
-- alistairwest, Jun 27 2005


This never worked for me, but mine was just a little pelty. I'll see if maybe peltier is better.
-- bungston, Jun 27 2005


You'll need a lot of power for good cooling. Not that this means it won't work. I like it.
-- Madcat, Jun 28 2005


Good point Madcat, my rudimentary calculations working within a budget of £10-£15 came up with approx 1 degree C of cooling per hour for a litre of water. Could probably increase to around three degrees with an increased budget, hmmm...
-- alistairwest, Jun 28 2005


Under the same conditions, how fast is ambient heat raising the water temperature? This would work better if the water was in a thermos flask with solar panels on the outside.
-- david_scothern, Jun 28 2005


For the sake of my (very rough) calculations I already assumed a pretty good level of thermal insulation. SInce I found the maths far too difficult to do, I turned to the internet and thought that a decent thermos flask seemed to equalise about 2 degrees an hour with a temperature differential of 25 degrees.
-- alistairwest, Jun 28 2005


Ooh, I'm definitely going to bake this (well, the annos). I've been thinking of getting a battery powered fridge/coolbox for a while and solar would work well here (Middle East). Yay, soldering.
-- marklar, May 28 2007



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