Zhu Bangquan experiments on a second-hand diesel engine with newly-extracted diesel in Chongqing municipality, China, on June 18, 2012.[Photo/CFP]

Zhu Bangquan, 63, after retiring from a soap factory in Chongqing, started extracting biodiesel from hogwash oil — oil re-processed from waste sources such as animal parts or recycled from fryers, with homemade experimental apparatuses, Chongqing Evening News reported Wednesday.

"The news said that petroleum will be depleted in a couple of decades", said Zhu, "I want to do something that will not only benefit my family, but also the whole society. That's when I had the idea".

Zhu spent around 1,000 yuan on experiment apparatuses and a second-hand diesel engine, and researched into a book on how to extract biodiesel. Also, he goes on a search every night for hogwash oil outside small restaurants and always ends up with about 3kg of hogwash oil, the newspaper said.

Six months later, Zhu extracted almost 100kg of biodiesel and tried to sell it to fishing boats by the river.

"People think I'm absolutely crazy trying to sell those (self-extracted biodiesel), so I started to give them out for free", Zhu said.

Finally, Zhu's ambitious plan was called off by local social workers because his experiment might cause an explosion if handled incorrectly.

Zhu said all he needs now is a safe location and a stable source for hogwash oil so he can carry on with his work, according to the newspaper.