They are registered as clean development mechanism projects, eligible for carbon credits. On October 15, 2010, the regional officer of Chhattisgarh Environment Conservation Board (CECB), R K Sharma, visited Tilda industrial area in Raipur unannounced. He noticed thick smoke rising from the premises of a renewable energy project. On paper the 8.5 MW power plant, Agrawal Renewable Energy Project, uses rice husk, a cleaner alternative to coal, to produce electricity. The electrostatic precipitator (ESP), an emission control device, installed in the plant was tripping frequently. On probing further, Sharma discovered that the plant was using coal as fuel.