Identifying clean, affordable and renewable cooking solutions for local people on Inhaca Island in Mozambique

Abstract: Inhaca Island is situated outside Maputo in Mozambique and is one of the globally important areas for forest conservation. The forest provides a number of societal, environmental and economic goods. Electricity and LPG are available on the island but is for most people too expensive to use for the household’s most energy intensive activities, such as cooking. Instead, all of the 25 interviewed households use firewood for all or some of their cooking activities. The use of firewood on the island is unsustainable and is causing deforestation. Also, the combustion of biomass inside houses causes indoor air pollution, which leads to an increased risk of infection to those who are exposed. To significantly reduce or end the use of firewood for cooking within a near future three renewable alternative cooking methods have been identified: solar cookers, biogas digesters and wood stoves. These solutions do not require new logistical solutions or transport of fuel to or on Inhaca Island, which is important since roads and transport possibilities are poor on the island. Households with no fuel cost have little money to spend on a new solution and without help from outside investors or the government, alternatives are slim. An improved cook stove or a wood stove in the lower price range might be possible for these families to purchase and the main argument is a potential time save and improved health. With a fuel expense for the household of 50 USD per year, panel cookers are the best financial option. Wood stoves could also be a good alternative in spite of the higher financial risk. A wood stove would slow down deforestation more than a panel cooker would. If the household spends 200 USD annually on fuel for cooking, and has enough animals and organic waste to produce a sufficient amount of biogas, a fixed dome biogas digester is the best alternative. A fixed dome biogas digesters require a very large initial investment and might therefor not be possible to implement without part time payments, subsidies or loans. Float drum digester is also an alternative and is less expensive than the fixed dome digester. Other good alternatives are parabolic solar cookers or wood stoves and here the choice between comfort and financial gain will decide which solution is most suitable for the family. For a household spending 500 USD on fuel for cooking annually, the conclusion is the same as for the group spending 200 USD per year with the addition of a balloon digester. All digesters are still expensive options and if the family is already spending 500 USD on fuel it is because they already use some comfortable fuels such as gas or electricity. It is therefore unlikely that they would surrender some of this comfort to have a solar cooker, requiring more time, cannot smoke and is not compatible with all the current equipment. A wood stove would therefore probably be preferred over a solar cooker.