Salome Alweny
Kampala
The jatropha carcus tree, if exploited, will not only relieve Uganda of dependency on fossil fuels from oil producing Arab countries but may also go a long way in becoming a major source of income
It is around us on the hedges of our homesteads, in the garden supporting other climbing plants and acting as fences for cattle kraals. While we complain about the ever-increasing fuel prices, we do not know that we are sitting on a rich oil shrub.
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This amazing shrub is the jatropha carcus tree locally known as ekiroowa in Luganda and among the Langi's as Omara Omara. The plant naturally produces seeds with up to 30-40 percent oil content, a source of fuel.
When dried and crushed, the seeds yield oil, which can be burned in most diesel engines, Reuters news agency reported on July 13. A commissioner for energy at the ministry of Energy and Mineral Development Eng Ben Todwo confirms that jatropha seeds can be processed into biomass to power electricity plants, hence substitute for kerosene for lighting and heating in homes.The seedlings of this shrub yield seeds in the first year after plantation but begins yielding oil in the second year. After the first five years, the typical annual yield of a jatropha tree weighs 3.5 kilogrammes.
The tree remains productive for up to between 30 and 40 years as it also absorbs carbon dioxide from the atmosphere. Hence one who has it in his garden or kraal could also earn from the sale of carbon absorbed by it if Uganda starts exploiting this other source of income.
One can harvest one up to 25 tonnes of processed oil, rising to a maximum of 12.5 tonnes in the fourth year. Research shows that 2,200 trees can be planted per hectare (approx 1,000 per acre) where one hectare should yield around seven tonnes of seeds per year. So one hectare of land should yield around 2.2-2.7 tonnes of oil.
The oil pressed from four kilogrammes of seeds is needed to make one litre of biodiesel for running diesel engine vehicles. The member of Parliament for Maruzzi County in Apac District Mr David Ebong says this plant has a big potential for large business enterprises and that it comes at a time when the cabinet of Uganda has approved renewable energy policy where all petroleum companies in Uganda will be required to blend their fossil fuels (oil) with 20 percent plant oil/biodisel.
A plant pathologist who heads the Cereals Research programme at the National Agricultural Research Organisation Dr George Bigirwa, says there is big potential for business in Jatropha carcus as the shrub can grow almost everywhere in Uganda.
"It can grow even on marginal lands like sandy, saline and on the poorest stony soil," he says.
This plant is not only important for biodisel, it also enhances soil productivity.
"When oil is squeezed out of the plant seeds, the refuse (seed cake) can be taken back to gardens and range lands as organic manure for it is rich in nitrogen, phosphorous and potassium," says an expert in biofuels based at the National Forestry Authority John Begumana.
Mr Begumana argues that the fertility value of Jatropha carcus to the soil can only be compared to chicken droppings and therefore has the potential of increasing the carrying capacity of grazing lands.
He gives an impression that one who chooses to deal in it can actually get income from the sale of the seeds and higher yields from the soil. "Jatropha can be intercropped with other cash crops such as coffee, sugar cane, fruits and vegetables and therefore little chances that it will compete for land with food crops and cause food insecurity," he adds.
The shrub originated from the Caribbean and spread as a valuable hedge plant to Africa and Asia by Portuguese traders.
Today it is widely used in India, Indonesia, the Philippines and Egypt as a quick growing source of oil-bearing nuts that can be pressed to produce biodiesel for running cars.
Research shows that rail lines between Mumbai and Delhi is planted with Jatropha and the train itself runs on 15-20 per cent biodiesel.
Other sources show that Jatropha has also been a crop of choice in development programmes in Africa where local villages have grown Jatropha on small plots of land and have hand-pressed the oil for use in generators, sewing machines and small motors.
Glycerin, a by-product of Jatropha oil, can also be used to produce soap while Glycerol, a by-product of bio diesel refinement, can be sold in India for around 45-70 pounds per kilogramme.
Other bio fuel crops that can be used to produce energy are Areurites mollucana (Kabaka njagala), Soya, sugarcane, groundnuts, palm, oilseed rape and sunflower.
Apart from bio diesel, other forms of bio fuel include bio ethanol, bio dimethylether and biogas.
Bio ethanol is produced from crops such as sugar cane, corn, beet, wheat and sorghum.
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Bio fuels however have for a long time met strong resistance from environmental experts who argue that growing bio fuel crops makes farmers dedicate much of their land to grow "food for cars" and forget growing "food for their stomach" hence causing food insecurity.
In some parts of the world, bio fuel crops have also met resistance from foresters who say that the current rush for the green energy is threatening forest reserves and wetlands and generally biodiversity in plants and animals as most governments are now dedicating them to international investors for growing bio fuel crops.
However, proponents for bio fuels argue that bio fuel has potential to reduce green house gas emissions by partially replacing fossil fuel with oil as a transport fuel.
They further argue that with bio fuel, countries could meet their commitments under the Kyoto Protocol which expects countries to reduce their carbon emissions by at least five percent from the 1990 levels and therefore mitigate the effects of climate change, according to a report "international trade in bio fuel" by Annie Dufey of the International Institute for Environment and Development.
This plant, if exploited, will not only relieve Uganda of dependency on fossil fuels from oil producing Arab countries but may also go a long way in becoming a major source of income.For Uganda, bio-diesel production, especially in adequate amount, could relieve the country of estimated $230 million spent on importing diesel per annum.
Mr Twodoa says Uganda imports more than 400,000,000 litres of diesel per annum.
