Field Trials of Electrical Heat Storage Cookers in Nepal
Update of article in BP27 by Urmila Simkhada - ITDG
Prototype electric heat storage cookers with hot air heat transfer are undergoing field trials in the villages of Salleri and Ghandruk, Nepal. Twenty cookers are being closely monitored as a means of understanding their effect on household energy use and to incorporate modifications to future designs based on the views of the users themselves. The results of the trials will not be known until March 1993, but the following is an account of the use of the cooker in one household in Salleri.
Mana Maya Nepali, aged 43, is a rural Nepali woman who comes from a low caste (traditional tailor, according to the Nepali caste system), and has lived in Salleri for the last 28 years.
The village has changed a lot in the last two decades. When she first came to the village there was plenty of forest but now houses are standing instead of forest. So firewood collection was not a problem but today it is a big problem. The housewives have to spend extra hours for firewood collection, which makes their lives more difficult than in the past.
Mana Maya has been using a heat storage cooker (HSC) since January 1992, and finds no problems with using it. The technology is so simple that anybody can use it. It is slower than a traditional stove but easy, comfortable and economical. The HSC has fitted well into her family. Different kinds of cooking vessels can be used, the kitchen looks clean with less smoke, and there has been no change in the Nepali cooking practices. The cooker fulfills three quarters of the cooking requirements and saves a significant amount of firewood. Now Mana Maya has more control over her time.
Mana Maya can spend more time on tailonng which will help her to earn some extra money. During the last winter, her daughter joined a three month skill development training course organised by Cottage Industry. So with the use of her HSC Mana Maya's life style has been changed.
The HSC project helps us to use the energy supplied by our new micro-hydro schemes to heat our cooking stoves when it is not needed for anything else.
The Heat Storage Cooker looks similar to the traditional Nepali wood stove; the two separate parts, cooking surface and the outer container, are joined together. The major components of the cooker are the heat storage container, enclosing pebbles and a 250w element; some stainless steel pipes and 60kg of rice husk ash surrounding this; bamboo with clay stones; wood and clay for the outer container, and a fan. The HSC is able to cook when an electric fan blows air through the pebbles, to reach a temperature of 300 degrees centigrade. The air emerges from holes in the cooking nozzle and a simmering nozzle can heat pans even if they are battered.
Salleri now is connected with a regular power supply of 200kW from the Salleri Electricity Utilization Company jointly managed by a Swiss and Nepali Company. It is very keen to introduce alternative uses of electricity to increase its load factors. To encourage electric cooking among the local people the Company has distributed HSCs to some of the families at a subsidised rate.