The testing of cookstoves: data of water-boiling tests as a basis to calculate fuel consumption

Abstract

The introduction of improved cookstoves is a means to reduce the consumption of cooking energy and, in the case this energy is consumed in the form of wood or charcoal, to reduce or slow down deforestation. The introduction of gas and kerosene stoves can help to achieve the same goal, though other problems may be introduced by the dissemination of these kinds of cookstoves. Before introducing improved stoves data should be available concerning the fuel savings that can be expected from the improved stoves compared to the traditional cookstoves. This data can be obtained in several ways and different test protocols exist to perform this testing, varying from fuel consumption measurements in the households over controlled cooking tests to water-boiling tests in a laboratory. In the fuel consumption measurements and controlled cooking tests the amount of fuel to perform a cooking task is determined, while the water-boiling tests determine power and efficiency of a stove. Fuel consumption measurements and controlled cooking tests are time-consuming and show an important variation in the results, which means a relatively large number of tests must be realised to get a meaningful average. Water-boiling tests are simple to perform and show consistent results, and these results are technically interesting, but do not determine fuel consumption. This article presents a method to use the results of water-boiling tests to arrive, by calculation, at a fuel consumption number. Therefore, first the concept of the power regime is introduced. This is the sequence of phases of the cooking process during which a stove has to deliver high and low power during a cooking session. Next the method by which the results of the water-boiling tests, combined with the power regime for the preparation of a certain meal, can be used to calculate fuel consumption for that meal is explained. The results of the calculation method are compared to the results of controlled cooking tests for two cases, Senegal and Mauritania, for which data of water-boiling tests and controlled cooking tests are available. The conclusion is that the calculation method can be used to predict fuel consumption of a cookstove from the results of water-boiling tests.