New research suggests bricks made out of the ashes from coal fires are both structurally and environmentally solid. UPI reports that the alternatives to clay bricks, which take more energy to produce, are also cheaper, LiveScience reported. Traditional clay bricks need extreme heat for production, while coal ash bricks can be made at room temperature.

Coal plant operators are already required to remove the ash from their chimney exhaust. About 70 million tons of fly ash is captured in the United States each year. If it‘‘s not used, it gets buried.

Currently, one-third of the collected ash is recycled into road beds and building materials. Up until the Freight Pipeline Company succeeded in making freeze-thaw resistant fly-ash bricks, the material couldn‘‘t be used because they could not survive freezing and thawing.

FPC also demonstrated that toxic mercury contained in the fly ash does not escape the brick so they aren‘‘t toxic. Henry Liu, president of FPC, said his research found the bricks absorb mercury, not emit it. Liu estimates 18 million tons of fly ash could supply the roughly 9 billion bricks that the United States goes through each year