But a humble shrub which grows on the side of the main road through the village is revolutionising their lives.

By crushing the seeds of the hardy jatropha plant, long considered largely useless, the villagers can power a small generator with its oil, enough to run 40 streetlights and give 60 families power by night.

"There is a general satisfaction among the population. The children gather under the lights in the evening and it has limited thefts," said Benben Doumbia, 47, one of the village elders, proudly explaining how the new machine works.

"Now our activities can continue until 11 o'clock in the evening, whereas before everything stopped at 6. People can visit each other. It has become an instrument of social cohesion," he said, speaking the local Bambara language.

Mali hopes eventually to have all its rural villages running on jatropha and other renewable energy sources such as solar power, making them self-sufficient and leaving the farming industry less vulnerable to fluctuations in world oil prices.

Simiji is one of around 700 communities so far to have installed a generator which can run on the plant oil, part of a state-run project to electrify the former French colony's 12,000 villages at a price affordable to their inhabitants.

The generators, housed in mud brick huts, also power a small millet grinder and a dehusker to process nuts.

"To stop the rural exodus in this country you have to start by creating a minimum standard of living," said Aboubacar Samake, head of the jatropha programme at the government-funded National Centre for Solar and Renewable Energy.

"People have to have light, to have cool air, to be able to store vaccines, even to watch national television. As things stand, a snake can bite someone in a village and they have to go to (the capital) Bamako to get a vaccine," he told Reuters.

SELF-SUFFICIENT

Africa produces a range of crops that could be use to make biofuel, including sugar cane, sugar beet, maize, sorghum and cassava -- all of which can be used to make ethanol -- and groundnuts, whose oil can be used to power diesel engines.

Some scientists argue using such crops for fuel in some of the poorest parts of the world risks worsening food shortages.

But jatropha, an inedible shrub, can be grown alongside other crops. It repels insects, needs little care and can grow in the most arid land, preventing soil erosion and making it ideal as a natural fence to protect other plants.

"They came to explain the project to us and said that if we grow jatropha it can produce oil to make the machine work," said Daouda Doumbia, 53, a Simiji elder.

"I grow groundnuts and this activity can go alongside it as a partner crop," he said, throwing water from a bucket over a small plot of jatropha bushes.

Interest in biofuels is booming around the world, triggered by high oil prices, energy security fears, limited spare refinery capacity and concerns about climate change.

Some developing countries are hoping to cash in on the boom: the president of neighbouring Senegal wants Africa to become the world's primary supplier of biofuels, while India has set aside 1.72 million hectares of land for jatropha cultivation.

But Mali's ambitions are more modest, for the time being.

Samake said a raft of private companies, some from as far away as France and Israel, were interested in developing a jatropha industry in Mali. But they had been told no biofuel would leave the country until its own needs were met.

"We don't intend to produce biofuel to send abroad but to satisfy the energy needs of the 80 percent of Malians who live in rural communities," Samake said.