Considering that the greatest amount of energy of a household is used in the kitchen a more sustainable solution for energy than the ordinary ones – gas, electricity and solid fuel, is needed. Therefore a solar battery (figure 2) can be installed to produce a completely sustainable energy which is also cost saving in long term.
One another solution for not developed countries could be the solar cooker (figure 3). Because of its qualities like simple construction, not expensive, easy installation and sustainability its popularity in the countries from the “third world” grows extremely fast in nowadays.