Discovering an affordable and cleaner burning alternative energy source has long been the dream of industrial chemical engineer Robert Manurung.

Inspired by the difficulty of finding firewood in his hometown in North Sumatra, the 50-year-old native of North Tapanuli set out to find a cheaper energy source.

In the next six months, the Bandung Institute of Technology expert just might realize his dream. Oil produced by the castor-oil plant, known locally as pohon jarak (Jatropha curcas L), which Manurung has been studying for sometime, will on a trial basis replace diesel oil to generate electricity in East Nusa Tenggara.

His discovery, called Jatropha oil, was greeted with pessimism by several colleagues at the institute, some of whom said "it was nothing new".

"But that pessimism motivated me to keep studying until I achieved real results," he said.

It is true that Jatropha oil is not exactly new. When Japan occupied the country, it used oil from the castor-oil plant to light up the night and to move its war machines. But after Japan left, the oil also disappeared.

Castor-oil plants grow on parched land in East and West Nusa Tenggara and in parts of Java. In the traditional community, the leaves of the plants are placed in water and used to fight fevers. Some farmers in Java use the plants to separate their crops.

From the grass family, the plant is between three meters and five meters high. The oil itself comes from the oval-shaped dark seeds of the plant.