What role can biogas play in meeting Africa's energy needs? Tullow Group scholar Zephaniah Kivungi, winner of the Scottish AmeyCespa award for his dissertation on creating energy from waste, explains.
Africa is growing rapidly. Its economies are expanding, in some cases, at a staggering rate. Huge multinationals compete to get a foothold in its growing markets. There is greater political stability and more predictable policy-making environments, as transparency and objectivity in governance increase.
But does Africa have the energy supplies to meet and sustain this growth and development?
The complexity and inadequacy of energy supplies in Africa
Currently, over 80 per cent of the continent’s 1.2 billion people live in the dark – literally – depending on unrefined biomass (wood, charcoal and cow dung) for fuel. These energy resources are dwindling as exploitation exceeds replenishment. Sub-Saharan Africa (SSA), according to the International Energy Agency in 2015, has scores of countries with single-digit electrification rates. Some countries, like Chad, have just one per cent while Liberia, South Sudan and Somalia have four per cent and below. Ten countries in SSA have less than 15 per cent electricity penetration, with rural areas worst hit. In some cases, penetration is zero per cent.
But why is electrification vital for Africa's growth and development? Well, electricity is clean, easy to use and much more efficient than these biomass resources. Its absence is a recipe for slowing things down, whether in the kitchen, the farm, or the school. For instance, millions of women in Africa spend almost entire days searching for firewood, with babies clutched on their backs. It takes hours to search for this fuel, and then hours to make a meal. It's no wonder that other areas like education and agriculture suffer.
A major challenge is the cost of energy. Save for the oil-rich north, most households in Africa would not use electricity to cook, even when they have access to it, because it's expensive. This is the number one reason why alternatives are required. On top of this, the population is growing faster than the supply rate of clean energy (that is, electricity). This explains, albeit partly, why the rate of access has remained mostly unchanged for decades.
Another challenge is the sparse distribution of populations across rural areas. Extending a power line by 500 kilometres to serve a community of 10,000 people is a noble idea but does not make business sense. It’s little wonder, then, that some countries have zero per cent rural electrification, while in 2013, 56 per cent of all electricity used in Kenya was in its capital.
Creating energy from waste (EfW) and the benefits of biogas
Food is produced under energy-intensive conditions. By the time it's cast away as waste, whether as food waste or animal manure (animal and human), a significant amount of energy is still embedded in it. Arguably the best way to recover this energy is through the use of a digestion system. This gives off biogas – a methane-rich mixture of gases produced when digestion of organic material happens in oxygen-deprived conditions. Over the years, a wide variety of digestion systems have been developed. It's even become possible for households to have a do-it-yourself version, making biogas an excellent, and natural, alternative to other energy supplies.
With organic waste so commonplace in Africa, the question remains as to why biogas systems have not led to an energy revolution of sorts. The answer has to do with stigma and a lack of awareness; for many people, waste, especially animal and human waste, is to be cast away and shunned.
And yet biogas can be generated from the pit latrines in the countryside by the ton. It can be obtained from sewage tanks in small and large towns. Indeed, after processing, biogas can be upgraded and bottled in the same way as everyday cooking gas. Given the complexity and inadequacy of the energy supply systems in Africa, this odourless gas presents a unique solution.
But despite all the evidence in its favour, it's hardly ever included in the national energy policy statements. Biogas is often viewed as a last resort. While rural electrification receives the bulk of available resources, governments still wonder aloud why they have been unable to save forests and why respiratory and cardiovascular health problems continue to increase.
The potential of biogas to meet Africa's energy needs
Research has shown that organic waste in the city of Nairobi, Kenya, can produce 906 gigawatt-hours (GWh) of electricity per year, and nationally biogas has an annual potential of 3,916 GWh. Given that Kenya has an annual electricity production of 7,849 GWh, biogas could supply half of its needs. This would be similar for many other, largely agricultural, African countries. It's worth noting that waste can come in the form of crop residues such as bagasse, or remains from the pulping process in paper factories, or brewing and distillery sludge. The potential is massive.
Another scenario would be if all rural schools in their thousands were to install biogas digesters. By using biogas for cooking and heating, they would each save up to an acre of forest. The cost of energy would come down as a result, and the economic ripple effect would be felt at national – even regional – level.
A further scenario involves creating biogas from the notorious water hyacinth, which has infested tropical freshwater bodies in the last two decades. From the largest freshwater body in Africa, Lake Victoria, to a constellation of other lakes like Kyoga, to the multi-country Niger River Basin, to the mighty Nile and Congo basins, the water hyacinth devastates aquatic environments, and not controlling it can lead to economic losses.
But what if processing plants were set up to digest the weed? Locals could be employed to harvest it, thereby clearing the lakes and restoring fishing activities. This would produce tonnes of biogas every day. Not only that, but the slurry from any biogas digester is a potent organic fertiliser – cheaper and more sustainable than mineral fertiliser. Such a scenario could lead to self-sufficient communities with better education, health, nutrition, food security, safety and, of course, clean energy. This last scenario is the model around which Africa Sustainability Centre (ASCENT), has developed its Clean Energy Village in Africa (CEVA) programme.
Biogas and a better future for Africa
Biogas can spur grassroots capitalism and social enterprise. It definitely improves the health of those in the countryside and the urban poor. It can rid the cities of stench and improve the livelihoods of urban populations. This will happen faster if there is support from the top echelons of policy-making. There also needs to be a shift from a small-scale approach to developing more efficient, larger digesters serving schools and entire communities. New enterprises are entering that domain, like FuCore International in Kenya.
Finally, beyond policy and business, investment support will be paramount, such as providing access to credit, structured training, and so on. The smoky stoves will be extinguished from the African kitchen as the continent takes off.
The Tullow Group Scholarships are vocational, technical and postgraduate scholarships available to individuals in Tullow’s operating countries in Africa and South America, and are managed by the British Council. Find out how you can apply for a Tullow Group Scholarship. Application deadline: 31 March, 2015.