A new biodiesel plant in Cuba -- the first of its type -- is turning seeds from the so-called "bellyache bush" into a green energy source, it was announced Monday.

Jatropha seeds are rich in oil but toxic for human consumption, explained Jose Sotolongo, director of the province's Center for Applied Technology for Sustainable Development.

"It's a major change to the widespread paradigm in global biofuel production," Sotolongo said, explaining the industry has so far mainly used edible vegetable oils, such as sunflower or soybean.

The jatropha plant offers the additional advantage, he added, "that its cultivation is feasible in areas of low or no agricultural value."

The small factory in Guantanamo province, on the eastern end of the island, is capable of producing over 100 tons of the fuel per year, according to the website of a local television station.

The factory was built with Cuban state funds, along with support from the Swiss Agency for Development and Cooperation.

Sotolongo said about 130 acres of jatropha were planted at Guantanamo to supply the factory, adding that the first few liters of fuel have already been used successfully to power agricultural machinery in the area.

The seeds have traditionally been used on the island to fight intestinal parasites and to lower fevers, but only in small doses because it can be toxic.

Cuba already uses sugar cane or forest biomass to produce electricity.

The communist nation, which currently imports half of its fuel from close ally Venezuela, has said it aims to generate a sixth of its electricity from renewable sources before the end of the decade.

It is also exploring for oil in its part of the Gulf of Mexico. The United States and Mexico, which also border the body of water, already produce oil from wells on the Gulf coast.