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Solar Cooking & Baking: Design assumptions for Solar Cooking & Baking
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Design assumptions for Solar Cooking & Baking

  • A rough guess is that the sun facing surface of a usual solar cooking box is about 0.3 m2. The Fresnel mirror of our setup is about 10 m2,
  • Transmission losses from mirror to in the kitchen located stove could be as high as 90%, but the time of exposure to the sun (8h) compared to the actual time use for cooking ( 2.5h) in a solar box could be 3 times higher.
  • Cost of the system may not be a constraint. The mirror holding frame is simple local construction work. The mirrors could be made from plastic with a high reflective coating, tensioned up in the frame. Piping mild steel or RVS. Also for a RVS container holding the molten salt, possibly the most expensive part, as it contains the oven space and the insulated doors.
  • Subsidizing from the government is likely when total prohibition of cutting wood (like in Morocco) asks for offering an alternative. A rough calculation of the damage done in the valley where we worked by the Hurricane Stan in 2005 was estimated Euro 7 Million for about 10.000 people, say 6 person per household, thus more then Euro 4000 per family. General application of the solar stove for cooking and baking tortillas subsidized by the government could probably be done for less then this amount.
  • Present cost for one day firing the usual stove that is reasonably efficient and answers the needs for cooking and baking tortillas well, is about 0,7 Euro. This for the better off. The poor gather their fuel wood themselves, having to walk longer distances every year between one day and half a day.
  • Better air to breath in the house and specially in the place where cooking is done makes a great difference in health. Research should quantify this.

Solar Cooking & Baking: Design assumptions for Solar Cooking & Baking
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