Kenya’s reliance on biomass energy for cooking remains significant and is even expected to increase due to population growth, urbanization, and limited access to cleaner energy sources (Namaswa et al., 2022; Okoko et al., 2017). Recent data from the Ministry of Energy in 2019 revealed that approximately 70% of households in Kenya rely on woodstoves, with a majority still using three-stone open fires. Other cooking technologies, such as charcoal stoves, LPG stoves, and kerosene stoves, make up the remaining percentages, with electrical appliances, biogas and liquid biofuels remaining marginal (MoE, 2019). In addition to the cooking technologies, the procurement of wood and production of charcoal mostly is very inefficient, resulting in low conversion efficiencies and increased health risks (Namaswa et al., 2022; Obure, 2022). Most charcoal producers use traditional earth kilns, which have a yield efficiency of only 10%, meaning that, for example, 100 kg of wood is needed to produce 10 kg of charcoal (Njenga et al., 2019). These practices along the whole value chain pose significant environmental challenges, including unsustainable fuelwood harvesting, deforestation, land degradation, biodiversity loss, and greenhouse gas emissions (Hollands & Daly, 2023; Karanja & Gasparatos, 2019).

These challenges are leading to the development of alternative solutions that use bioenergy more sustainably and efficiently. Sustainable biomass energy sources, such as briquettes and pellets from forest and agricultural residues, bioethanol, and biogas, have the potential to reduce pressure on forest resources and address pressing issues such as deforestation and land degradation. By reducing the demand for fuelwood and traditional kilns, these solutions contribute to the preservation of Kenya’s forests and woodlands. This, in turn, helps safeguard biodiversity, mitigate greenhouse gas emissions, and maintain environmental health (Karanja & Gasparatos, 2019; Namaswa et al., 2022). The key to their success lies in environmentally friendly production methods that carefully select raw materials as well as production technologies (Okoko et al., 2017). In addition to the environmental benefits, sustainable biomass-based cooking solutions can improve the livelihoods of both rural and urban communities. Instead of relying on imported fossil fuel-based energy sources like kerosene and LPG, locally produced biomass energy supports job creation and income generation (Namaswa et al., 2022). Overall, these solutions align with Kenya’s socio-economic objectives as outlined in the Climate Change Act 2016 and the Nationally Determined Contribution (UNEP, 2019). Nationally Determined Contributions (NDCs) are at the heart of the Paris Agreement and represent each country’s efforts to reduce national emissions and adapt to the impacts of climate change.

Briquettes and pellets are one alternative fuel to firewood and charcoal. They are made by compacting raw organic matter into moulds of shapes and sizes suited for use in a briquette stove (Okoko et al., 2017). In Kenya, sawdust as well as crop residues from the production of maize, cassava, sugarcane, potatoes, bananas, coconuts, macadamia nuts or avocados are among the materials that are converted to fuel. Fuel briquettes are cheaper and burn cleaner, more evenly and for a longer period than wood fuel. Besides, briquetting organic residues contributes to cleaning the environment and closing resource use gaps (Njenga et al., 2019). Photos 1 to 3 show avocado residues and sawdust which are used or tested as raw materials for briquette and pellet production, and finalized pellets.