Croton tree injects new life into national effort to produce biofuel

A tree normally grown as a wind breaker or planted as a fence by Kenyan farmers now offers a new opportunity for biofuel production.

Kenya had set its future biofuel hopes on the jatropha but now the croton tree, a non-food crop known as mukinduri in central Kenya, and Chepkeleliet, Lemaruguet, Masineitel, Mkigara, Mlalai, Muhande and Musine in various other parts of Kenya, is promising equal opportunities in the quantity and quality of biofuel, according to biofuel experts.

Kenya is currently in the process of identifying the best combination of non-food crops to use to produce biofuel to supplement the country’s voracious appetite for fossil fuels whose cost of import is the equivalent of Sh120 billion every year.

The push for biofuel is driven in part by its potential to benefit rural communities by offering them a new income stream.

James Mwangi, a small holder farmer based in Naro Moru, has pioneered the processing of croton tree nuts to produce fuel. The filtered fuel is then used by consumers to run their modified diesel car engines or fed directly into generators to produce electricity or pump water.

Mr Mwangi runs a community-based organisation that started as a group to help farmers market their pyrethrum in the area. It was through research that they discovered that nuts of croton tree could produce fuel.

Partners in Holland carried out further tests on the fuel and discovered that it has one of the highest fuel content levels of the crops that have been identified as suitable for the production of biofuel among them rapeseeds, avocado and jatropha.

The use of croton nuts for biofuel is seen as a new window of opportunity for the renewable energy industry in Kenya as doubts mount about the viability of the jathropha crop, both locally and globally.

Currently, the Ministry of Energy’s biofuel strategy is anchored the jatropha. Its proponents claim it can grow in arid and semi arid areas and has high fuel content, but the growing body of evidence suggests otherwise.

A global research on jatropha conducted by University of Twente in the Netherlands found that the crop requires more water than other biofuel crops.

Although the plant survives more easily than others without water, it would need substantially more water than soy, corn or sugar beet to produce enough fuel for comparable amounts of energy, the research conducted mid-this year found.

“There is a misunderstanding that plants that are drought resistant can do well without water. During this period of drought, the plant doesn’t grow,” said Prof Arjen Hoekstra of the University of Twente.

The researchers found that jatropha needs an average of 20,000 litres of water for every litre of biodiesel, well above the 14,000 litres needed by rapeseeds biodiesel.

Another study conducted by the Nairobi-based African Centre for Technology Studies (ACTS) in October last year called for more research on the viability of Jatropha.

Yet another report this year sponsored by Friends of the Earth group based on experience from Swaziland found that although jatropha does grow in semi-arid lands, yields in these conditions are very unlikely to be high enough for farmers to make a profit.

In water-scarce Swaziland, some farmers growing jatropha have found that the crop needs regular watering to make it viable for the production of biofuel.

Ms Warigia Mahinda, who promotes the growing of croton nuts, says the fact that the tree grows in most parts of the country makes it a more viable option.
Experts say the nuts have a fuel content of up to 35 per cent, which means one can obtain 0.35 litres of biofuel from a kilo of croton nuts.

According to Ms Warigia users of croton nuts fuel have reported getting 30 per cent more mileage over a comparable quantity if fossil fuel.

David Newman of the Edelevu Energy, which promotes use of renewable fuel, is one of the users of the croton nuts fuel for power his pick-up.

Special generators
He uses the standard diesel engine for four wheel drive pick-ups, but has added a separate heater and filter through which to pass the croton nuts fuel before it enters the engine for combustion.

He purchases a litre of croton fuel for Sh70 compared to current pump price of Sh75 per litre of diesel.

But Mr Newman’s interest is not so much in using the fuel for running diesel-powered cars as there are additional costs attached to modifying engines.

Rather, he is interested in generators which are designed to run on either diesel or croton nuts fuel.

His company is importing special generators to Kenya which will offer cheaper running costs and grow the market for croton fuel.

Analysts estimate that the cost of small scale production of fuel from croton is between Sh50 and Sh65 per litre, depending on whether there is a viable commercial channel for the residue that remains at the end of the pressing process.

The fuel can be used in a generator without going through an additional conversion process. But if it is converted into biodiesel, one needs to account for an additional Sh20 per litre for the cost of the equipment, and other related costs which pushes the retail cost to anywhere between Sh75 and Sh95.

Rural economy
But these costs have been computed based on Kenya’s existing output levels and are expected to decrease if the as production levels increase.

Proponents of croton fuel use argue that even if its cost is equal to that of fossil fuel, it is preferable because it will benefit farmers, and uplift the rural economy while saving the country foreign exchange spend.

The use of biofuel will also enhance Kenya’s capacity to earn from the global carbon trade which rewards projects whose activities limit the emission of carbon dioxide into the environment.

Although the croton tree has traditionally been grown as a wind breaker, as a fence or for charcoal, increased overcrowding in certain parts of the country, the tree is increasingly being cleared to make way for food crops.

However, its new use is bound to regenerate interest to plant the fast-growing tree. Mr Mwangi says he has contracted women groups in and around Naru Moro area to become outgrowers.