The renewables industry received a pleasant surprise last week when 71,326 ‘renewable energy certificates' were traded on the two exchanges, IEX (62,277) and PXIL (8,949). That volume in the very first month of the financial year was encouraging. But a major seller was only one company, Orient Green Power Ltd, which sold 20,939 REC in the market, worth about Rs 4.5 crore.Orient Green Power of the Chennai-based Shriram Group, has substantial wind and biomass capacities in Tamil Nadu and is (consequently) suffering from delayed payments from the state distribution company, TANGEDCO. The REC mechanism has come in handy for the company. In the current year, the company is expected to generate over 6 lakh RECs, worth about Rs 100 crore.