A Parabolic Focus
Many people on the planet do not have a good way to cook their meals. Having enough food may be one problem but finding fuel to cook it is often another major issue.
In 1st world countries we turn a knob and a gas or electric cooker generates enough heat to cook our meals and we think about it no more. If we cook using wood or charcoal its for an outdoor BBQ to entertain friends and encourage some under the stars camaraderie.
It would get old fast if we had to collect the wood often from miles away and carry it back on our shoulders every day and then cook over a poorly designed hearth which smoked into our eyes and nose.
Modified Coal Pots - An Improvement on Wood
This is how 2 billion+ people on the planet cook, often in poorly ventilated spaces where smoke inhalation becomes a public health issue. Inhaled particulate matter from woodsmoke is a killer that goes way back in time.
The mummified remains of many ordinary people from pre-history show signs of having succumbed to soot in the lungs acquired from longterm exposure to cooking fires. Most of these were female since they did most of the stove work.
This is still a public health issue in many parts of the world. Many people in the rain forest regions of South America use only wood, others charcoal made from wood. In Tanzania for example they have largely switched to more efficient stoves which use less wood and produce less smoke. But they still produce CO2 and worldwide 1.5 billion people still cook off wood burning stoves in the 21st century.
Don't worry about the pollution caused by your backyard BBQ, whole forests are cut down daily to supply the cooking needs of the many. One notable example, Haiti has been virtually denuded of timber, its neighbor, the Dominican Republic's forested area survived thanks to the draconian policies of its Dictator Joaquin Balaguer who for 22 years made forest preservation and erosion control a priority not lightly transgressed.
Pompeiian Mark II updated - Still in Service
Other more efficient means of cooking are being developed, some using stoves that use the same fuel more efficiently but my favorite, especially for tropical regions is a solar cooker.
Catching the energy released by the sun, doesn't always have to be done by relatively expensive to manufacture solar cells. Focusing a ray of sunlight through a magnifying glass as a way to start a fire is a method we are all familiar with. Focusing sunlight using a parabolic mirror or reflector is a somewhat less familiar technique.
But using inexpensive materials it is possible to construct a solar cooker, with a radius of upto 5 metres
(15 ft) which can be used to supply solar cooking power, hot water heating and greywater filtration. It uses natural sunlight as the main source of energy and can heat food directly while also being used to heat water in a closed circuit boiler system.
A Small Exhibition Model
The Dish is built from bicycle parts and plastic vanity mirrors to create the surface of the dish which concentrates the energy of the sun on a pot or stove in the kitchen or alternatively on a boiler or heat exchanger. Coupled with some solar cells or a wind generator whichever is appropriate it can supply the complete power needs for the kitchen.
It was originally designed for use in communal facilities in squatter settlements in Mexico by the people at Basic Initiative. It is a system that could be widely deployed to take some of the load off people and the ecosystem in places with abundant sunlight.
Basic Intiative Solar Cookers
Design for the Other 90 Percent
