Gasifier Stoves

Gasifier stoves - Science, technology and field outreach

From the article:

This paper is concerned with the development of a new class of single pan high efficiency, low emission stoves, named gasifier stoves that promise constant power that can be controlled using any solid biomass fuel in the form of pellets. These stoves use battery-run fan based air supply for gasification (primary air) and for combustion (secondary air). Design with the correct secondary air flow ensures near stoichiometric combustion that allows attainment of peak combustion temperatures with accompanying high water boiling efficiencies (up to 50 % for vessels of practical relevance) and very low emissions (of carbon monoxide, particulate matter and oxides of nitrogen). The use of high density agro-residue based pellets or coconut shell pieces ensures operational duration of about an hour or more at power levels of 3 kWth (∼12 g/min). The principles involved, the optimization aspects of the design are outlined. The dependence of efficiency and emissions on the design parameters are described. The field imperatives that drive the choice of the rechargeable battery source and the fan are brought out.

The process development, testing and internal qualification tasks were undertaken by Indian Institute of Science. Product development including improvements on the ceramic chamber, battery pack, the fan and the final shape of the stove on the one hand and the fuel pellet production process on the other were dealt with by First energy Private Ltd (denoted by FEPL). The process of business development was of course completely dealt with by FEPL. Close interaction at several times during this period has helped progress the project from the laboratory to large scale commercial operation.

This technology was initially developed as a business by BP, India (earlier) and subsequently taken on by FEPL. At this time, over four hundred thousand stoves have been sold in four states in India. Oorja-Plus is widely sold currently and Oorja-Super is yet to enter the market. The implications of such developments to the domestic cooking scenario of India are briefly brought out.