Growing billions of litres of “green petrol” in Africa sounds like a great idea. Who would argue against planting crops that can be turned into a fuel that propels aircraft, cars or tractors as efficiently as petrol or diesel?
Biologically derived fuel (biofuel) could become a major, renewable resource that strengthens the domestic energy security of African nations while saving foreign currency wasted on imported fossil fuel.
This emerging, homegrown biofuel industry could create millions of jobs and possibly help arrest the impact of global climate change by reducing greenhouse gas emissions.
Yet, the drive to convert large swathes of Africa’s land surface into biofuel plantations for the global aviation and transport industry has massive implications for the continent’s 1.3 billion people, its food security, water and vanishing wild spaces.
Does it really make sense to grow petrol for the aviation industry instead of food on a continent where the human population is growing rapidly and millions already go to bed hungry?
A new study suggests that sub-Saharan Africa has the potential to supply up to 90% of the “sustainable biofuels” required for the global aviation industry. But the price tag could be millions of hectares of land ripped up to make way for biofuel crops.
On paper, the study suggests there is potentially nearly 5.5 million km2 of land available to plant biofuel crops, roughly 23% of sub-Saharan Africa’s total surface area of 24.3 million km2. Only about 1.9 million km2 was deemed “very suitable” for several types of biofuel plants, however, because of varying climatic factors. But that’s still a massive chunk of land, larger than Kenya, Uganda and Tanzania combined.
Ploughing up virgin grasslands and shrublands to plant biofuel on this scale would also release large volumes of the carbon currently locked into this soil and vegetation, defeating the goal of reducing greenhouse gas emissions from fossil fuels.
Therefore, the study suggests, only a much smaller area of 800 000km2should be considered ideal for biofuel crops, without releasing excessive carbon emissions from land-use conversion.
That’s also a whopping pile of land, though, slightly larger than the surface area of Namibia. And if this new cultivation area included land that is considered “moderately suitable” for a narrower range of biofuel crops, the land needed is about twice the size of Namibia.
These are some of the conclusions of a report published by World Wide Fund for Nature (WWF) South Africa and Vienna-based International Institute for Applied Systems Analysis (IIASA), funded by the Boeing corporation.
WWF economist Tjasa Bole-Rentel and her fellow researchers say the aviation industry now generates nearly 2.5% of global carbon dioxide emissions, or possibly 5% of the overall gas emissions that contribute to human-induced climate change.
Further rapid growth suggests that the aviation industry alone could be generating 22% of human-generated CO2 emissions by 2050.
Bole-Rentel and her colleagues say that, as a result, the aviation industry is placing much hope in alternative fuels and market-based measures to achieve its goal of carbon-neutral growth from 2020.
But even if large volumes of biofuel can be blended with conventional aviation fuel to achieve lower carbon emissions, this new fuel source cannot be considered truly sustainable if it impacts negatively on food security and the environment.
The authors of the report therefore set out to provide a “realistic assessment” of the current and future biofuel production potential of countries in sub-Saharan Africa, based partly on sustainability criteria set by the independent Roundtable on Sustainable Biomaterials (RSB).
These criteria take into account human food and water security, the protection of forests, wildlife reserves and livestock grazing.
Most promising crop
The WWF/IIASA report suggests that the “most promising” biofuel feedstock so far is miscanthus, a tall and fast-growing Asian grass species that can be grown over a wide geographic range.
Other potential biofuel crops include sugar cane, oil palm, jatropha (an oil-rich flowering plant from Central America) and Solaris (a nicotine-free variety of tobacco).
The report also identifies several countries considered to have high potential for large-scale biofuel plantations, including South Africa, the Democratic Republic of the Congo, Madagascar, Ethiopia and Mozambique.
Apart from the serious threats that biofuels pose for human food security in Africa, the WWF report cautions that there could be negative ripple effects on the environment, water security and soil erosion.
For example, planting biofuel crops could lead to further fragmentation of the wild habitat of these areas, blocking off animal and plant migration corridors, plus other “far-reaching negative impacts on ecosystems around the converted land”.
Converting virgin grasslands and shrublands could lead to overexploitation of soil nutrients, compacting of topsoil layers, soil erosion and more intense use of fertilisers and pesticides.
Depending on which biofuel crops were chosen, there is also the risk that some crops would become invasive and spread beyond the cultivated fields.
Other researchers have also suggested that African nations and farmers will need to consider carefully the implications of turning over more land to growing biofuel crops, such as the impact on food prices and food security, and the potential dispossession of communal land.
Dr Graham von Maltitz and his fellow researchers at South Africa’s Council for Scientific and Industrial Research (CSIR) have noted that much of the African land targeted for biofuels is owned communally.
“Communal landowners do not have secured, individual tenure to the land’s resources … Where land is governed by a chief or traditional authority, economic benefits to the traditional authority or community as a whole may well overrule existing resource use rights enjoyed by individual members. Caution must be used, however, given the increasing evidence that local or customary leaders do not always act in the community’s best interests when there are personal benefits to be gained,” said Von Maltitz.
In a report published in 2009, he said it was impossible to quantify how much land had been turned over to biofuel production in Africa so far, although on a continental scale the proposed biofuel expansion could translate into “tens of millions of hectares”.
But in a more recent series of research papers, Von Maltitz tempers these concerns, noting that most jatropha biofuel proposals in Southern Africa over the past 10 years had collapsed.
Failed ‘miracle crop’
Von Maltitz said several governments and investors punted jatropha as a “miracle crop” during the early 2000s.
Mozambique announced a decade ago that it had received formal proposals to establish 12 large-scale jatropha plantations worth $298 million (about R2.2 billion at the time), but it appeared that most never got off the ground.
Madagascar had similar plans to develop nearly a million hectares of jatropha.
“People got this idea that jatropha would produce six to eight tonnes of seeds per hectare and that it could also grow in poor soils and in drought,” said Von Maltitz.
In practice, however, yields in many plantations seldom exceeded half a tonne per hectare, and eventually most jatropha projects in Madagascar, Mozambique, Tanzania and Zambia had collapsed because of a combination of low yields, over-optimistic business plans, a lack of markets and the 2008 financial crisis.
Pros and cons
In a research paper published last year, Von Maltitz and his colleagues cautioned that future expansion of the biofuels sector in Southern Africa would require careful assessment to avoid unintended consequences.
“If biofuels development clears natural areas, and biofuels are produced from low-yielding crops, grown with heavy inputs of water, fertilisers and energy, and/or processed into biofuel using fossil energy, they could threaten food security and generate as much [or more] carbon emissions than petroleum fuels.
“However, if developed appropriately, biofuels offer an opportunity for the production of renewable energy and a reduction in carbon emissions, together with the development of more integrated and sustainable agricultural systems and improved natural resource management,” his research group concluded.