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Experimenting the positioning of cooking pots in solar cookers.

During visit to solarcooking.org site there is a topic requiring attention, i.e. whether to stack the cooking pots side by side or to stack them?

While experimenting with modified funnel cooker "Parvaticooker" we found that stacking works better. Details of our experiment are given below.

Our next goal was to cook 2-3 different dishes. For this purpose we used a large stand and placed three identical pots as above side by side, with 750 ml of water in each. We measured temperature in all three pots after 90 minutes and readings were 70 ⁰C, 77 ⁰C and 77 ⁰C there was no improvement with different positioning pattern.

Then it was decided to work with pots stacked on each other. With available aluminum pots we were able to stack only two pots. We decided to work with stainless steel pots that come with pressure cookers. In aluminum pots we placed 750 ml of water while in SS pots we placed 1 liter water in large pot and 750 ml water in smaller pot. ( SS pots had diameter of 6.25 " , height of big pot is 2.75" small pot is 1.75")

Temperatures recorded after 80 minutes is given in table

This test clearely showed that stacking of cooking pots works better than keeping them side by side in concentrator type cookers

We repeated same experiment with three SS pots stacked on each other.

Temperatures recorded after 90 minutes is given in a table below.  

From this result it is evident that solar cooker with does even heating of pots in stacked position.

Some friends advised us to use aluminum cooker pots which are used in box type cookers. We again repeated the above experiment by using these containers (Dimensions 6" diameter and 3" height). Temperatures recorded after 90 minutes are as given below.

While trying to find out the reason for this variation we found that even though aluminum is better conductor these containers have lids and contact between them is not perfect. SS cooker containers are made to fit tightly on each other. Getting similar aluminum containers has been difficult so far, since people tend to by only SS containers.

 Parvati Solar cooker. We are selling 26" diameter Parvati solar cooker with fabricated rotating metal stand and hard anodized reflector. Price Rs 4399/- FREE SHIPPING within India.

 Full size plans  available. (Full size Plans of 24 sided 26 inch diameter cooker only printed copies available.Us$ 8 as printing and postage charges)

Mrs. Parvati Green Tech Enterprises, Sahakar Nagar, Parvati, Pune India Pin 411 009.