3 Arnold et al. also concluded that the rapid rise in charcoal production—which requires large quantities of wood to manufacture—warranted further investigation, especially where urban demand for charcoal was rising against the backdrop of the global population migration from rural to urban areas. The statistics from the Food and Agriculture Organization<sup>3</sup> show that global charcoal production doubled from 26 million tonnes in 1980 to 54 million tonnes in 2020. During the intervening four decades, Africa’s share increased steadily, from 44 percent in the first decade (1980–1990) to 53 percent in the second decade (1990–2000), 57 percent in the third decade (2000–2010), and 63 percent in the decade ending in 2020. With wood fuel representing more than 90 percent of all wood harvested, Africa lost 3.94 million hectares per year of forest area between 2010 and 2020, the highest net loss of any region, followed by 2.60 million hectares per year in South America. Africa is the only region of the world where the total forest area decreased steadily in three successive decades from 1990 to 2020 (FAO and UNEP 2020).

Household use of wood fuels has far-reaching effects beyond cooking and heating. An estimated 880 million people worldwide spend part of their time collecting fuelwood or producing charcoal, many of them women. More than 40 million people, or 1.2 percent of the global workforce, are engaged in commercial fuelwood and charcoal activities (FAO and UNEP 2020). To the extent that those collecting fuelwood for own consumption can free up time, clean household energy provides an additional benefit. But to the extent that charcoal production and firewood gathering for sale is bringing income to 40 million people, the loss of revenue would initially present a socioeconomic problem. Such activities could even provide social stability. A study collecting primary data in 2011 in Sierra Leone found that 63 of 64 charcoal-producing villages visited during the data collection had not been involved in charcoal production prior to the civil war. One charcoal trading village consisted entirely of ex-combatants who had turned to cooperative charcoal production as their exclusive source of income (Munro, van der Horst, and Healy 2017).

As the sense of urgency about biomass use driving global deforestation has abated, the last two decades have seen a growing recognition of the high human cost of air pollution from household use of fuels emitting harmful pollutants. The World Health Organization in 2018 estimated, based on updated data from 2016, that 3.8 million a year died prematurely from illnesses attributable to elevated concentrations of PM2.5—particulate matter with an aerodynamic diameter of 2.5 microns or less—caused by emissions from household use of solid fuels and kerosene for cooking.<sup>4</sup> An updated estimation for 2019 shows that the number of premature deaths from household air pollution had declined to 2.3 million (HEI 2020), but there were large regional differences. South and East Asia had made considerable progress in reducing the number of people exposed to household air pollution, driven by China and India, which had the largest reduction in the total number of people exposed between 2010 and 2019. By contrast, despite the declining _percentage_ of the population exposed, several countries in Sub-Saharan Africa with rapidly increasing population saw an increase in the total _number_ of people exposed. Globally, in the 17 countries with more than 50 million people and at least 10 percent of the population living in households with solid fuel use, five countries saw a net increase in the number of people exposed to household air pollution in the two decades, all of them in Sub-Saharan Africa.

In light of the foregoing and additional concerns about the toll—especially on women and children—of the drudgery of fuel collection and additional labor and time associated with cooking with solid fuels using traditional stoves, the United Nations General Assembly in 2015 adopted the resolution,<sup>5</sup> “Transforming our world: the 2030 Agenda for Sustainable Development,” with 17 Sustainable

> 3 http://www.fao.org/faostat/en/#data/FO. 4 https://www.who.int/news-room/fact-sheets/detail/household-air-pollution-and-health.

> 5 https://undocs.org/en/A/RES/70/1.