To boost its green credentials, the Taiwanese government wants all pig farms on the island to adopt the pollution practice and have offered farmers a cash incentive to get with the program. Farmers are also being told that less watery manure will attract higher sale prices.

"To use the pig waste as manure is a very good approach within the spirit of green energy, much better than just letting it go to waste and pollute the river water," said Stephen Shen, head of Taiwan's environment department. "And I think that can help us a lot in decreasing CO2 emissions and fighting global warming."

There are approximately six million pigs in Taiwan. The government estimates that if all pigs used the 'toilets' 180 million litres of water used per day in cleaning would halve.

The toilet consists of a series of iron bars installed above 20 centimetres above the floor int he corner of a pen.