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Energy poverty—the lack of access to electricity and clean cooking technologies—remains a critical challengein sub-Saharan Africa (SSA), particularly in rural areas. Cooking is often carried out using inefficient andpolluting traditional cookstoves, which contribute to indoor air pollution, pose significant health risks(resulting in a substantial burden of disease and mortality), and have environmental impacts. In thiscontext, improved and advanced cookstoves are promoted as a pathway toward modern energy services.Understanding the combustion and emission performance of biomass cookstoves and the properties ofemitted aerosols and particles is crucial for mitigating the impacts of traditional cooking and supportingpolicymakers and practitioners in implementing cleaner cooking systems. Furthermore, integrating cleanercooking technologies into sustainable bioenergy systems can promote evidence-based strategies for modernenergy access and eradicating energy poverty.The research presented in this thesis comprises four appended articles. The state of knowledge on biomasscookstove emissions is analysed through a systematic literature review (Paper I). Through two experimentalstudies, the combustion and emission performance and aerosol and particle properties are assessed from awide range of cookstove-fuel combinations tested under laboratory (Paper II) and field conditions (PaperIII). Additionally, the biophysical potential of a novel agroforestry-bioenergy system is evaluated (Paper IV).The results show that more advanced cookstoves generally perform better regarding combustion efficiencyand emission reductions. However, the trends are not strictly linear and are influenced by specific fuel types.Across the technological gradient, aerosol emissions were generally reduced in laboratory and field settings,with consistent overall trends toward lower particle number concentrations and size distributionsdominated by smaller particles for the more advanced cookstoves. Similarly, emissions of carbonaceousspecies, as well as of organic and inorganic compounds, also decreased along the gradient. However, theeffects of specific fuel types and properties—occasionally related to fuel upgrading—and cookstove-fuelcombinations presented exceptions to these overall trends. The biophysical assessment of the proposedagroforestry-bioenergy system demonstrates that sustainably produced on-farm biomass can not only meetthe annual fuel demand for cleaner cooking systems—with surplus—but also provide additional woodybiomass for electricity production through gasification, potentially benefiting neighbouring rural or periurbancommunities.In conclusion, the research presented in this thesis contributes to the field of sustainable bioenergy systemsin SSA by: (1) analyzing the current state of knowledge on biomass cookstove emissions relevant to healthand environmental impacts; (2) generating new insights into the combustion and emission performance, aswell as aerosol and particle characteristics, of a wide range of cookstove-fuel combinations tested under bothlaboratory and field conditions; and (3) proposing an integrated agroforestry-bioenergy system with thepotential to enhance energy and food security in rural SSA.