Re: windmill composter / Minto\'s Wonder Wheel/super magnifier
Hi Guys,
Now this IS getting interesting. /w3tcompact/icons/smile.gif
I agree that the "summer sun" on the hopefully-cooling tanks is a "no-problem" issue, solved simply by a piece of canvas or plastic tarp for shade. The "cooling mist" sounds good too! A small sprinkler head at the "rest" position of each of the "cooling" tanks could do the trick, with the "heating" tank being shielded(from the water-fallout, but not from the sun).
An interesting but probably not-practical heat source idea is a large fresnel lens focused on a black metal heat-exchanger plumbed into the tank-heater bath-water. I say this because I have several of the (40" square?) plastic lenses such as are sold (or at least used-to-be) by Edmund Scientific, and have experimented with them a little in the sun.
With the lense supported on a frame at the focal length (I seem to recall about 50"), the "hot-spot " (claimed to be 2000-3000 degrees f.) IS for sure HOT!
I timed a pot of water coming to a boil, and it was pretty quick, though I don't remember the time.
The hot spot looks like a flashlight beam on the target, and with no hiss or smoke to remind you what is going on, is easy to carelessly pass your hand through, while positioning things, or measuring temperature, ...YEEOOUUCH!! NOT-RECOMMENDED! You will move your hand very-quickly, I can report for sure! /w3tcompact/icons/shocked.gif
Amazing how much energy is available from a square-yard or so of sunlight. /w3tcompact/icons/crazy.gif
A collector(funnel) of panels/mirrors could gather the energy from several times the area, ...not simple to align properly, but scary if accomplished.
Drawbacks: 1. Must "track" the sun's movement, or the spot will soon move off-target.
2. Not sure how the plastic material of the lens itself will hold up to the UV degradation of extended exposure.
3. Only operational during the hours when sun-position and cloudless sky cooperate.
With a modicum of "cooperation" though, the water in the bath should retain enough energy to heat the tank-to-be-emptied fairly quickly, without losing too-much heat, until the clouds moved-on, and more energy could be absorbed.
"Don't try this at home!" may be overstating things, but kids playing with this thing w/o adult supervision is a no-no! It's DANGEROUS!
You have to be constantly watchful that you don't carry it in such a way that the sun comes in focus on anything you don't want burned. For a comparison, consider this: When I held a lit-match to a piece of dry cardboard, it started to "flame-up" after some number of seconds. When held under the lens, it was burning NOW!! Nearly instantly!
To others who may have been (as I now shamefully admit ) "mad-scientists" as kids, and might have toasted an ant or two during sunbeam experiments, this thing is the "hydrogen-bomb" of magnifying glasses! /w3tcompact/icons/tongue.gif
Are we havin' fun yet?
Keep those ideas comin', boys and girls! /w3tcompact/icons/laugh.gif
Larry