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.