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Orchestrated communal research project to provide soonest solar powered cooking and baking facilities in every house within the limits of 30 degrees of latitude N & S.

Please visit also our wiki research pages. (D22)

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Solar Cooking & Baking
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Idea on paper Twentyfold cost reduction Applicable in modern as well as in poor economies Environment Income Rural as well as urban.


  • Stop deforestation
  • Prevent land slides
  • Increase comfort
  • Support for rural communities
  • Within economic reach of the poor
  • No smoke that endangers health

NB project is limited to tropical areas 30 degrees meridian North and South

Mix high + low tech:

  • Heat transfer with heat pipe with forced internal fluid circulation
  • Heat collector with adjustable Fresnel mirror arrangement
  • Heat storage in molted salt or otherwise
  • Separate heating circuits for cooking (150 C.) and baking (300 C.)
  • Additional booster heating if solar input is too low or need extra capacity

Commonly used wood stove, also for baking tortillas

Stove is solar heat sink for cooking in oven and baking on hot plate

Additional information
Mix high tech + low tech:

  • Heat transfer with heat pipe with forced internal fluid circulation
    Different from the solar box or parabolic mirror cooking arrangement, in this setup the full plan area of the house is available for solar heat collection. Heat transfer using the heat pipe principle may need forced circulation.
    An alternative for a heat pipe is molten salt, characterized by a high heat storage capacity. Use of molten salt also asks for forced circulation. For initial melting of the salt a thin fluid filled pipe is mounted inside the pipe that holds the molten salt.
  • Heat collector with adjustable Fresnel mirror arrangement
    Indicated in the drawing is a fresnel mirror of 2 x 5 meters. Heat collected a pipe parallel to the mirror strips is conducted to the stove arrangement.
  • Heat storage in molted salt or otherwise
    Heat transfers from the heat pipe into a heat collector consisting out of stone mass or molted salt or similar.
  • Separate heating circuits for cooking (150 C.) and baking (300 C.)
    Sun in its highest position, delivering the highest temperature heats a separate circuit that is linked to a heat buffer shaped for baking food when needed. When 300 C. is not attained in the collector pipe, this pipe is linked to the cooking section of the cooking arrangement
  • Additional booster heating if solar input is too low or need extra capacity
    A small stove fired with gas, charcoal or wood is designed for fast heating up and for delivering a temperature adequate for baking, when the heat input by the sun is not sufficient.
How the development of this design initiative can be organized:
  • Start with wide publication of the idea with some basic data and inspiring illustrations under a Open Source or Creative Commons licence.
  • Coordinate the info sharing on a special portal and initiate work groups
  • Let research be done by student groups with backing of universities and institutes.
  • Initiating many local experiments in a competitive setting.

Light steel construction hold plastic mirror strips focused on heat pipe

Insolated stove has over for cooking and a hot plate for baking

Internal links

Questions relating to Solar Cooking and Baking

Temperature and thermal capacity needed for cooking and baking

Design assumptions for Solar Cooking & Baking

A number of assumptions that guided the design are listed in this note. By and by information on it being true of false will trickle in. Then this list will be updated.

The temperature we need

In search of basic data for 'Solar Baking and Cooking' we have to look at the actual temperature that is needed, the time needed for actual baking. Next we have to find how much heat is needed and at what level for the other heating tasks, such at heating water for laundry.

Design assumptions for 'Solar Cooking and Baking

Design assumptions for this design are a rough guess. They should be updated as soon as new data and ideas come in.

Tortilla's should not result in barren mountain slope

Regarding this design initiative for the solar stove. I have no idea if it CAN be done, I only know it HAS to be done. When I was there in the valleys around this lake Atitlan I was horrified by the scale of deforestation. All these strong man with a huge stack of freshly cut fuel wood on their backs, in numbers descending the mountain slopes.

External Links

  • Solar Cookers International (SCI) spreads solar cooking awareness and skills worldwide, particularly in areas with plentiful sunshine and diminishing sources of cooking fuel. Since its founding in 1987, SCI has enabled 30,000 families in Africa to cook with the sun's energy, freeing women and children from the burdens of gathering firewood and carrying it for miles.
  • : Solar Heat Storage has been realized by Gadhia Solar ( ) . This shows the feasibility of this project approach. : Solar Home Energy Center
  • Google search for "Solar Cooking contruction manual"
    Go to 'Images' for getting a fast over view of many possible designs and practical applications. Specially look for the all-local experiment with a solar box/heat sink combinatoin as done in Tanzania deep down at that page.

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