for sharan, it's very much a work—in—progress. the aspiration. now let's turn our attention to something you may not even associate with climate change. no, not the vehicles driving down the street, or even the energy used by the buildings here in downtown mek‘ele. what i am talking about is the stuff the buildings are actually made of. i'm talking about cement. as countries develop, they start to build and build and build. all this building uses millions and millions of tons of, yes, cement. and cement produces huge amounts of carbon dioxide. 8% of the world total. so here's the question — can we make cement less damaging? well, the boss of one indian cement company says, yes, we can. he claims he's already cut emissions from his factories by 40% of the world average and he says he's going to make his factories carbon neutral by 2040. rajini vaidyanathan has been to see him in south india in tamil nadu. as india grows, so too does its use of cement, now only second to china. concrete buildings are changing the landscape here. but