Quantifying the additionality of cookstove carbon projects

Cookstove replacement is the fastest growing project type on the voluntary carbon offset market; yet the additionality of stove interventions remains understudied. Most carbon offset projects that disseminate efficient cookstoves assume that each new stove replaces a less efficient one, ignoring the possibility that some participating households would have acquired efficient stoves even without the offset subsidy. We quantify the rate that households would have procured efficient stoves without the offset program (non-additional stove purchases) by (1) identifying and analyzing existing datasets from past cookstove randomized control trials (RCTs) that assess the impacts of efficient stove interventions compared to control households without a similar intervention and (2) collecting primary data ourselves from neighbors of the participants in an RCT conducted by the first author. Our review finds that the average annual rate of non-additionality from the five published studies we identified and from our primary data collection, weighted for sample size and normalizing for time, is 4.2%. These studies, from sub-Saharan Africa, India, and South America, all took place in rural areas. Our review provides quantitative evidence that cookstove projects in rural areas can be highly additional, particularly in areas without government stove programming.