One morning, several years ago, a sudden, sharp bang outside my home caught my attention. Upon enquiry, the watchman revealed that whilst burning some rubbish, he had placed a plastic bottle on the fire with its lid firmly sealed, causing it to burst unexpectedly. This incident, though startling, is a rather commonplace occurrence in Malawi, where burning refuse is a deeply ingrained means of waste disposal.
During the dry season, trees shed their leaves, creating considerable untidiness in people’s yards and surroundings. It is customary for residents to sweep up these dry leaves into large heaps and set them alight, often without much thought for the consequences. Across the nation, countless small fires flicker in an effort to rid the land of unwanted dry waste, and frequently, bushes and undergrowth are cleared through burning, revealing a pattern of habitual, unregulated fire use.
One wonders if the populace has ever truly paused to consider the broader implications of burning waste—not only for the environment but also for ourselves. As refuse burns, it releases heat energy—energy lamentably squandered rather than harnessed for human benefit. Yet, many lament the pernicious use of charcoal and firewood as cooking and heating fuels in homes and institutions, persisting nevertheless in their use for lack of a viable alternative, despite the known environmental costs.
The numerous small fires ignited to burn organic refuse nationwide cumulatively produce thousands of joules of energy each year—energy lost entirely to waste. When waste is wasted, it is waste indeed. If our waste is only capable of causing plastic bottles to pop, as I witnessed just outside my home that quiet morning, it is a profoundly pitiful state of affairs. We, above all, ought to be the most lamented. But this need not be our fate. With careful and deliberate planning, the lost kilojoules of energy could be reclaimed, carefully channelled and utilised to partially bridge our country’s vast and widening energy deficit.
Plant matter and its remnants, such as leaves and stems, represent a valuable and abundant source of energy known as biomass. We must devise original and effective means of burning biomass to extract useful energy. Apart from maize cob remains—popularly known as zitsononkho—much residual agricultural biomass in rural areas is burned recklessly, the heat generated simply dissipating into the atmosphere.
All biomass harbours potential as an energy source. A promising method to extract this energy involves feeding the biomass into specialised units called gasifiers. Through gasification—a process akin to charcoal burning—the biomass is converted into synthetic gas (or syngas), which can then be utilised as fuel, either burnt directly or employed to run an engine powering an electricity generator. This would enable individuals to generate their own electricity independently, without relying on expensive and polluting diesel or petrol imports.
However, gasifiers remain prohibitively expensive for the majority of Malawians, rendering them an impractical solution for everyday households. A more feasible and accessible alternative lies in transforming biomass into briquettes, which can substitute firewood or charcoal for cooking purposes. Though it might seem challenging, creating such briquettes is achievable even with rudimentary equipment and local materials, making it a genuinely viable option for many.
The biomass can be finely chopped using a mortar and pestle. These particles are then mixed with a pulp slurry derived from waste paper, which has been soaked in water for several days, acting as a binder since biomass alone lacks cohesion. Alternatively, cassava powder soaked in water may serve as an effective, natural binder. The mixture is then pressed into a mould featuring numerous tiny holes at one end. Compression expels water from the briquette mixture, which seeps through the holes. Subsequently, the briquettes are left to dry in the sun over several days. Once fully dried, these briquettes burn efficiently, providing ample and reliable heat to boil water or cook nsima or ndiwo, reducing reliance on unsustainable fuels.
As a nation, we face an urgent need to resolve our critical energy shortages. The reliance on firewood and charcoal has ravaged vast swathes of our country’s once-lush and vibrant forests. This deforestation has triggered a cascade of environmental and social problems, including irregular rainfall patterns, excessive run-off, siltation of waterways, soil erosion, and unstable power supply. The introduction of biomass briquettes, as outlined here, presents a far more environmentally sustainable and socially responsible alternative, poised to replace firewood and charcoal, and conserve our precious natural heritage.
The answers to our challenges need not be sought beyond our borders. If we search within Malawi, we shall find that these solutions have long been at hand, patiently waiting to be developed and embraced.