Scientists have turned the ash waste from coal-fired power stations into a global environmental solution, which promises to slash emissions in the carbon-hungry construction sector by at least 20 per cent.

The solution is soon likely to be seen in India, with its creators in the process of negotiating a manufacturing license in the country.

Researchers at the University of New South Wales converted the pollution from coal furnaces, known as fly ash, into a new range of high-strength, lightweight building materials, ScienceAlert reported.

The first 100 per cent “made from waste” bricks are already coming off production lines in China, where hundreds of millions of tonnes of fly ash contaminate the air and clog waterways.

Apart from India, the university's commercial arm, NewSouth Innovations, is also negotiating to license the technology in Australia, Indonesia, the US, Dubai and Kuwait.

“The environmental consequences are enormous,” said inventor Obada Kayali.

The big greenhouse gas emission savings lie firstly in reducing the volume of cement needed to make high strength concrete.

Novel remedy

The new lightweight fly ash aggregate, known as Flashag, replaces quarried rocks such as blue metal and gravel which are usually mixed with cement to make concrete.

Flashag is the world's first fly ash aggregate to drastically reduce the volume of cement needed to achieve high strength concrete structures.

China, where half the world's construction is taking place, recently surpassed the US as the world's single biggest polluter. The fly ash products pilot plant opened in the Chinese city of Hebi earlier this year, in a special zone for sustainable industrial technologies and large scale industrial recycling.

“The amount of building going on in China and the pollution is unbelievable. If we can reduce the use of cement as much as possible there that is a very big gain, not only for China but for the global environment,” Kayali said.

The 100 per cent fly ash bricks, known as Flash Bricks, are also about 20 per cent lighter and stronger than their clay counterparts. This means further emissions savings because less steel and shallower concrete foundations are needed for the same sized structures.

Globally, coal-fired power generation has produced billions of tonnes of fly ash waste over the past century, with annual production now at about 800 million tonnes.