A scientist from Chittur near here, Prof. Narayanan Neithalath, who had won the $1.6 crore U.S National Science Foundation prize in 2008, has achieved another milestone when he developed ‘Green Building Blocks’ to replace cement with locally produced concrete blocks.

These new concrete blocks “are more economical, energy-efficient and environment friendly than traditional ones’’, says Prof. Narayanan, an expert on cement-based materials and sustainable concretes and an affiliate of Clarkson’s Centre for Advanced Material Processing (CAMP).

“They are also stronger and more durable. And all of these improvements occur because 20 per cent of the primary - and most expensive ingredient in concrete, Portland cement, has been replaced with recycled industrial glass powder.’’, he said.

“What sparked development of these “green’’ blocks was a challenge faced by Potters Industries, a major international manufacturer of engineered beads made entirely from recycled glass. Its local plant was generating 8,000 tonnes of excess fine powder a year while making tiny pieces of high-tech applications that range from reflective highway lane paint to hypodermic needles. Potters sought an efficient use of this by-product, which looks and feels like greyish-white baby powder’’, he said.

When the new 56,000 square feet student centre opens its doors in August at Clarkson University, not only will the building enhance social and cultural life on campus, it will also exemplify how Clarkson research pays off in the real world, said the Clarkson University communiqué on the new discovery.

Ambat Gopakumar, father of Prof. Narayanan told ‘The Hindu’ here on Sunday, that the new green building blocks could replace cement one day and he is proud of his for making such a discovery that could benefit the world immensely.

Funded by the New York State Department of Economic Development Environmental Investment Programme and the New York State Foundation for Science, Technology and Innovation through CAMP, Prof. Narayanan began the project’s research in 2006 and concluded it in December 2008 after extensive field tests at Woodruff Block, a manufacturer in Potsdam. The company produced 7,5000 blocks for the students' centre using this innovative formulation, he said.

It is estimated that concrete is the world’s most widely used man-made material. Some 12 billion metric tons are churned out each year (a cubic meter for every person on the planet) as infrastructure for roads, bridges and buildings.

About 25 per cent of it is Portland cement, a limestone-based binder whose production significantly depletes natural resources and also stresses the environment. The costly, energy-intensive manufacture of cement, is a major source of carbon dioxide emission. Thus replacing it with powdered glass promotes sustainability by limiting pollution, reducing energy consumption, and preserving resources – and saves money by utilizing a far less costly leftover industrial by-product, Prof. Narayanan said.

Glass powder is effective in concrete primarily because it is loaded with silica, which can react with other cement components (calcium hydroxide, for example) to increase the material’s strength through hydration (which leads to hardening), he said.