What is Bioenergy?
- Bioenergy is a broad term that refers to any form of renewable energy produced from materials derived from biological sources. This encompasses not only liquid biofuels for transport, but solid biomass and biogas; each of which can fulfil different functions for African communities.
- Liquid biofuels most immediately provide an economically and environmentally sustainable way for countries to reduce their dependence on expensive fossil fuel exports. Yet biogas can also be used to generate electricity in microgrid and offgrid rural electrification projects, and both are essential components in the modern clean cookstoves that provide a healthy alternative to traditional biomass.
- PANGEA strongly supports all of these interlinked technologies, and works to raise awareness of bioenergy’s multifaceted potential.
Liquid Biofuel
- Liquid Biofuel refers to any liquid fuel source derived from organic matter, rather than conventional fossil sources. They provide significant greenhouse gas savings when used as an alternative to fossil fuels, and have accordingly been prioritised by the European Union as ….
- There are two main strains of liquid biofuel – Bioethanol and biodiesel – both of which are produced across Africa.
- Bioethanol is produced through the fermentation of sugars, starches, or cellulose, and can be mixed with any percentage of gasoline to provide fuel for transport. The most popular feedstocks for African governments have proven to be sugarcane and sweet sorghum, because of their prevalence and sustainability.
- Biodiesel is produced from oils or fats through a process of transesterification , and has a wide range of possible feedstocks: animal fats, vegetable oils, soy, rapeseed, jatropha, mustard, sunflower, and palm oil. As a fuel, it can be used in any diesel engine when combined with mineral diesel. Jatropha has been the overwhelming feedstock of choice for African producers, although many have been disappointing by disappointing yields and its complex farming process.
- For African governments, the economic benefits of liquid biofuel production are twofold. Firstly, it allows them to reduce their dependence on expensive imported fossil-fuels; and secondly – once this has been attained – it provides a valuable commodity to be exported to the international market, further increasing economic well-being.
Biogas
- Biogas refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen. It can be produced from various types of organic waste: dead plant and animal material, animal dung, kitchen waste etc.
- Biogas is produced using anaerobic digesters, in which an air-tight tank transforms biomass waste into methane producing renewable energy that can be used for heating and electricity. The produced fuel can have a high methane concentration; of up to 80-90% when using in-situ gas purification techniques.
- For Africa’s rural communities, it holds many benefits. Firstly, the organic waste can be harvested locally, with long-established farming and livestock systems providing the opportunity for self-sustainable renewable energy production.
- This means that production is cheap and non-weather dependent; and rural electrification can happen locally through micro- and off-grid generation, rather than being dependent on unfeasible national grid extensions.
- It is also increasingly being used as a fuel for clean cooking stoves, which can dramatically reduce fuel consumption and exposure to harmful charcoal in African communities. Electric stoves also reduce the time spent searching for traditional fuel sources each day, giving further health benefits.