Assessment of an energy-efficient metal chulha for solid biomass fuel and evaluation of its performance

The present study evaluates the performance of a newly developed improved metal chulha (IMC) over available traditional mud chulha (TMC) as an energy-efficient nonsmoking cooking appliance for the rural households. An extensive survey of 90 respondents revealed that majority of the households use firewood for cooking in energy-inefficient TMCs. The TMC emitted considerable amount of toxic component, which can adversely affect the human health on direct exposure. To overcome this problem, we have developed an IMC, which significantly reduces energy loss and cooking time compared to TMC. In this study, we have measured the level of airborne pollutants emitted from fuelwood used for cooking purpose. In addition to this, we have also studied the thermal efficiency of IMC over TMC. A major reduction in indoor pollutants viz. PM10 (45%), PM2.5 (73%), CO (51%), SOX (22%), NOX (36%) was recorded for IMC over the TMC. The water boiling test also indicates higher thermal efficiency during all the three phases: cold start (37%), hot start (41%) and simmering test (46%) for IMC over TMC. The fuel consumption rate (g min−1) was recorded 23, 16.6, 14 and 32.2, 25.1 and 20.6 for IMC and TMC, respectively. Compared with TMC, the IMC reduced specific fuelwood consumption, increased efficiencies and lower emissions of pollutants including PM10, PM2.5, NOX, SOX and CO. A social survey in the form of a questionnaire revealed that majority of households realized that IMC will be better than the TMC in terms of handling, reduced emissions, easier cooking and efficiency.