Longitudinal analysis and expected evolution of household fuel and stove stacking patterns in rural Mexico

Abstract

Household energy transition towards cleaner and more efficient devices and fuels has been posed as an urgent solution for 40 % of world population that depends on open fires for cooking. However, finding the “silver bullet” that allows the complete displacement of traditional woodburning devices has proven a major challenge, and the “stacking” of traditional and modern devices is the norm in rural areas. As a result, a major emerging research topic is the identification of the environmental and health impacts of “clean stacking” options that, by combining different fuels and devices, may actually be more effective in eliminating the use of open fires than single-fuel interventions. We conducted a longitudinal analysis of the multiple stacking options that emerge from a “Patsari” clean woodburning cookstove dissemination program in rural Mexico directed to households with-and-without previous access to liquefied petroleum gas (LPG). The analysis is based on a survey of 134 households belonging to 10 villages of Central Mexico, where household fuelwood consumption before-and-after the installation of the Patsari cookstove was measured. The analysis showed that: a) From the initial two categories of users (Open Fire and LPG) the adoption of Patsari stoves led to the emergence of six categories of users or stacking options (Patsari-alone; Patsari-LPG; Patsari-LPG-Open fire; Patsari-Open Fire; LPG-Open Fire; Open Firealone); b) When LPG is used in combination with open fires, there are negligible fuelwood savings; c) The largest reduction in emissions with regards to open fires (47.5 %) is observed for the Patsari-alone users; and d) the adoption of Patsari cookstoves led to 39 % fuel savings for exclusive fuelwood users and 48 % for mixed LPG-fuelwood users. Using a Markov Chain to project the future evolution of the different types of users, we find that instead of a smooth transition from open fires to Patsari stoves, 62.6 % of the users within five years, would be expected to stack different cooking devices; while 33.6 % of the users would only use the Patsari cookstove. It is also expected that 3.8 % of households will continue using the open fires exclusively or in combination with other devices. A sensitivity analysis with four hypothetical scenarios suggested that this model serves to make more realistic projections of the expected benefits of clean fuel and stove dissemination programs.