Solar powered heater

[KMoffett]

Something beyond two nails and a "suicide cord":.......a commercial version: **broken link removed**
Ken

From my previous post...and don't think you can find them commercially now.

 

[Valence_4]

Unless the rules of the game prohibit storage you might use a few solar cells to charge a battery - so there's enough power to do the job. You'd need to run some experiments to determine how much power to cook your hot dog - but once you've done that you can work backward.

Even before you do the experiments you can estimate the amount of power required to heat the hot dog from whatever the starting point is to 150 deg F. I know there is data available on energy required to cool/freeze various foods.

An extremely crude place to begin would be to measure the power (current and time) required to cook a hot dog by conventional means - a burner on the oven, a countertop toaster oven. Those are inefficient methods by any measure but they give you an upper limit. Maybe your rules don't limit you to a battery, inverter and toaster oven.

My science courses are far away, but i remenber that 4,2 joules (1 calorie) is the quantity of energy required to heat one gram of water by 1 deg. C.

150 deg. F = 65 deg C. suppose that you take the sausage fron the refrigerator (4 deg. C) you'll have to heat it up by 61 deg. C.

The Sausage mean mass is 56 grams. So to heat it up alone (no heating water), you'll need 56 * 61 = 3416 calories or 14,3 kJ.

At 100 watts, it will take 143 seconds (sightly more than two minutes) to heat-it up.

Bon appétit !

 

[Willbe]

At 100 watts, it will take 143 seconds (sightly more than two minutes) to heat-it up.

And an electric chair, at 2400 VAC and 4 to 8 amps, does about the same thing.

 

[Hero999]

As I've mentioned above, using electric solar cells is a silly idea because it's much cheaper and more efficient to focus the sun's rays directly on the sausage which will convert the radiation directly to heat.

 

[tekplague]

Thanks for all the help and ideas, we decieded to use a Fresnel Lens to focus all the light onto the hotdog. Covered in aluminum foil it cooks to 160 degrees F in less than 3 mins from the fridge. Withoiut aluminum foil it turns black instantly at the focal point and basicaly burns to a crisp.

 

[Hero999]

That's impressive, where abouts do you live?

Are you nearer the equator than the poler regions?

 

[tekplague]

I live in Kentucky, the lens were using is a 30"X40" out of an old big screen tv. I was really surprised by it also, but it basicaly takes every bit of the light that passes through it and focuses it at one point.

YouTube - FRESNEL LENS 1 SUN COLLECTOR VINTAGE GREENPOWERSCIENCE

YouTube - Solar Cooking, frying up some dogs

 

[mrlooneytoon]

Not enough to cook a hot dog. Google Solar hot dog cooker?
**broken link removed**
**broken link removed**

Oh man, just make sure you don't stand in front of that beast when you cook haha.

 

[blueroomelectronics]

Or put your face at the focal point.
Now here's a real hot dog warmer!
**broken link removed**

 

[CHOOCHOO]

Having made hot water solar heating that uses simply thermosyphon principle, using a bout an 8 gal. plastic pail with lid, 1/2" dia copper household piping with 90 deg elbows, all soldered, with a half days exposure to the Michigan (USA) sun it was more than hot to bathe/shower in.
Hence I suggest using scrap aluminum, be it heavy foil pans/cans etc, of same size, and arraying the pans via a simple rod embedded in a wood block same size as the pans. You also need a dished backer, perhaps even a 'simple' large plastic bowl or such. Locate the center of focus for your hot spot via an x'd string, now you simply start epoxying the pans edges to the dished backer. Continue in this manner, clipping sides of pans so you get
max coverage. Voila. Recycled cheap solar cooker for whatever you want, even a cup
of Java, be it instant?
It WILL work.

LarryinMICHIGAN USA

 

[tcmtech]

I had to play with this one this morning! I used line current 120v ran through a 60uf AC capacitor. Ran that current in and out a 3 oz breakfast sausage with SS screws. Time to cook to burst was about 3 minutes! Still tasted good for breakfast!
no math yet but cooking #2 as it type now!