Conference Paper

Key differences of performance test protocols for household biomass cookstoves

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Abstract

In this study, different ways of testing household biomass cooking stoves are compared and analyzed. The differences between test methods relate to the stove operation and data analysis methods, the fueling procedure, the end point selection, the choice of metrics and others factors. The influences of these differences were analyzed by using an induction heater. The results show the use of a pot lid or not, and the selection of the end point of the test have the greatest influence on the rated performance. Consequently test results provided by laboratories using different test methods will place the same stove-plus-fuel combination on significantly different performance 'tiers'. Also the results show some metrics in popular tests should be reviewed. Some recommendations are provided for improving the accuracy and repeatability of test procedures and select metrics are defined for greater clarity.

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... Still, criticism of the WBT has increased as further comparative studies against realcooking performance have been released [59,60], and as researchers raise questions about the rationale of some performance metrics [61]. Different authors [23,61] declare that it is impossible to predict ICS field performance without a user-centred approach, properly accounting for local burn sequences and practices. Based on this trend, the lack of an accepted standard and the spread of alternative protocols represent a major challenge for the success and effective evaluation of stove dissemination programs and carbon-financed projects. ...
... Studies from Bailis et al. [69] highlighted how relying on WBT thermal efficiency outputs, regardless of the relative importance of high and low power cooking tasks among the target population, can lead to misleading interpretations. Furthermore, Zhang et al. [61] and Jetter et al. [20] questioned the scientific meaningfulness of thermal efficiency at simmering. Indeed, this phase is characterised by highly variable steam production, which represents a heat loss in the energy balance but positively contributes to the efficiency value in the actual formulation of thermal efficiency. ...
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... It is worth noting also that the WBT 4.2.3 itself suggests interpreting this parameter only for the cs and hs phases of the procedure, as also stated in the ISO-IWA meeting of February 2012 [20]. As a matter of fact, Zhang et al. and Bailis et al. questioned the accuracy and utility of such indicators at simmering, respectively in [7] and [23]; indeed, simmering phase is characterised by highly variable steam production, which represents a heat loss in the energy balance which conversely contributes positively to the efficiency value in the actual formulation of g, as Jetter et. al. [24] highlighted. ...
... Note that some authors question the mathematical appropriateness of averaging these values[7], and alternatives are still under study. ...
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