Abstract. Airborne emissions from charcoal-making kilns commonly used in Kenya and Brazil were measured during typical operating conditions. Emission factors were determined nonmethane hydrocarbons, nitrogen oxides (NO.0 and total suspended particulates (TSP) along with charcoal production efficiency and charcoal and fuelwood carbon and energy contents. The conversion of wood carbon to charcoal carbon ranged from 37 to 69%, depending on kiln type. E•ssion factors, expressed as grams of pollutant per kilogram of charcoal produced, for the eight kilns ranged from 543 to 3027 for CO2, 32-62 for CH4, 143-373 for CO, 24-124 for total nonmethane organic compounds, 0.01 1-0.30 for N20, 0.0054-0.13 for NO.•, and 13-41 for TSP. On average, fuelwood carbon was approximately diverted as follows: 51% to charcoal, 27% to CO2, and 13% to products of incomplete combustion (PIC). Due to the higher global warming potentials (GWPs) of PIC relative to CO2 on a carbon atom basis, such kilns can produce rather large net greenhouse gas emissions, even when the wood is harvested renewably. Based on published GWPs for CO2, CH4, and N20 only, we estimate that 0.77-1.63 kg C-CO2 (carbon as carbon dioxide equivalents) is emitted per kilogram of charcoal produced. We estimate that the total primary global warming com•tment (GWC) of Kenyan and Brazilian charcoal-making kiln emissions is about 2.7 and 7.5 •11ion tons (Mr) C-CO2, respectively. For comparison, the primary GWC from fossil fuel use in the United States is almost 1700 Mt C-CO2.

The capacitive energy storage performance of activated carbon can be significantly improved by embedding graphene quantum dots owing to the formation of overall conductive networks.

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