If, however, the presently available animal dung is used through biogas plants it is possible to meet more than 80% of the present level of fuel energy consumption. In recent years the villagers are being encouraged to use solar cookers for cooking purposes. But this has raised serious problems that demand careful investigation.

First, solar cookers are best used only when there is sun. Otherwise, storage of this energy becomes costly. But the cooking schedule in village households is determined by tradition and in consistence with the working hours of inmates. Most of the households are generally engaged in cooking more than once a day and the percentage of households who cook during the noon-session is relatively small. The solar cooker can, accordingly, only act as a supplementary fuel source for rural families.

Secondly, the existing design of the solar cooker is suitable only for boiling, baking and roasting. But food preparation in India involves frying with oil and spices before boiling. This cooking procedure is incompatible with the current technology provided by solar cookers.

Thirdly, if the targeted users of solar cookers are poor families, this device has to compete with the traditional zero cost mud-built chullas. Besides, an important characteristic of the customary fuel use pattern in rural areas is that they are either home produced or collected from the common property. Existence of a sizeable amount of idle labour in the rural families helps this process. Individual household’s cash expenditure on fuel is accordingly traditionally nearly zero.

Introduction of any technological option or any new fuel material has to be in tune with socio-economic conditions, cultural and other practices in the village. New fuel materials and energy generating devices have to accommodate existing cooking practices of the rural poor, the type of foods they eat and their preparation process, and the quantity of food prepared at a particular time. But while the solar cooker has to be ideally placed outside the kitchen where there are direct sunrays, cooking in today's rural household is done inside the kitchen. Maintenance of solar cookers could be problematic too. The traditional chullas are built and repaired by female members of the family. But for the maintenance of the solar cooker, howsoever simple it may be, the family has to rely upon its male members and outside help. Above all, the present design of solar cooker is unsuitable for large containers, which are usually used by rural households since large quantities of food are cooked in one session.