India's double first in battle against climate change
Two world-leading clean energy projects have opened in the south Indian state of Tamil Nadu. A £3m industrial plant is capturing the CO2 emissions from a coal boiler and using the CO2 to make valuable chemicals. It is a world first. And just 100km away is the world's biggest solar farm, making power for 150,000 homes on a 10 sq km site.
The industrial plant appears especially significant as it offers a breakthrough by capturing CO2 without subsidy.
Built at a chemical plant in the port city of Tuticorin, it is projected to save 60,000 tonnes of CO2 emissions a year by incorporating them into the recipes for baking soda and other chemicals.
Here's how it works:
The plant operates a coal-fired boiler to make steam for its chemical operations.
CO2 emissions from the boiler's chimney are stripped out by a fine mist of a new patented chemical.
A stream of CO2 is fed into the chemicals plant as an ingredient for baking soda and other compounds with many uses, including the manufacturing of glass, detergents and sweeteners.
The owner of the chemicals plant, Ramachadran Gopalan, told a BBC Radio 4 documentary: "I am a businessman. I never thought about saving the planet. I needed a reliable stream of CO2, and this was the best way of getting it."
He says his operation has now almost zero emissions. He hopes soon to install a second coal boiler to make more CO2 to synthesise fertiliser.
The chemical used in stripping the CO2 from the flue gas was invented by two young Indian chemists. They failed to raise Indian finance to develop it, but their firm, Carbonclean Solutions, working with the Institute of Chemical Technology at Mumbai and Imperial College in London, got backing from the UK's entrepreneur support scheme.
Their technique uses a form of salt to bond with CO2 molecules in the boiler chimney. The firm says it is more efficient than typical amine compounds used for the purpose.