"First of our project is "Low Cost Solar Cooker". For this we selected Funnel Cooker by Dr. Steven Jones. While our experiments were being carried out we had found out that stacking of pots works better than placing them them side by side in funnel cooker. See these results here. Hence we considered the total size of stacked cooking pots as 6 inches in diameter and 6 inches in height.
We decided to improve this design. From the drawing we decided on a meeting point of sunlight that are reflected from the rim of the cone. ( Point 'x' in figure1). The second cone of 900 was started from this level (the reference for this was taken from Prof. Mann's (1981) improvement to VITA design). The length of 900 cone section was taken as 6.25 inches. The base was closed and made reflective, so that any sunlight passing from sides of cooking pot is reflected back. The diagram of this with sunlight reflection is shown in Fig 2. From the diagram concentration of sunlight on cooking pot is clearly seen. This cooker is useful for unattended cooking. Reflections of sunlight with respect to position of Sun for -60 minutes to +60 minutes is shown in fig 3. We had used pressure cooker cooking pots in stacked position with plastic cover. Opening diameter of this cooker is 24 inches. Basically this is a duel angle funnel cooker. We have named it Parvati Solar cooker."
See the Construction diagrams for the Parvati Solar Cooker for direction in making one.
An interesting aspect of this cooker is the greater cooking efficiency achieved when the cook pots are stacked, rather that set side by side in the cooker. Another designer, Christopher Jordan, is working on a simple solar panel cooker, the Solar Rice Cooker, that also allows for stacking cook pots. He is also experimenting with placing blackened bricks, as simple heat storage mass, under a fewer number of cook pots. It allows the oven to maintain a more even operating temperature in partly cloudy weather, as well as, extending the cooker's usefulness later in the day. The Parvati Solar Cooker would also have this capability. Adding bricks would have the additional benefit of stabilizing the cooker in windy conditions, though the cooker may require sturdy construction materials to handle the extra weight.
Plans in other languages
Audio and video
- The Terra Foundation's data sheet on this cooker
- Construction diagrams for the Parvati Solar Cooker
- New Parvati Cooker
See this article in our foreign language wikis
- Voyez cet article dans le wiki en français: Un four à deux angles: le four solaire Parvati