With another 500 MW of wind capacity expected to be installed in Tamil Nadu this financial year taking the state's installed wind capacity to around 3700 MW by the end of March 2007, grid congestion problems are in acute need of solutions, says the Tamil Nadu Electricity Board (TNEB). "TNEB has to cope with the marketing speed of private companies selling wind energy installations to their clients," says the utility. It is proposing investment of $125 million in increased transformer capacity and a new 440 kW substation. "Participation of private companies is essential for power evacuation and they are already participating in setting up the substation," says the electricity board. Turbine maker Suzlon Energy is showing the way. It has already built a transmission line to clear the bottleneck in Tirunelvelli. Tamil Nadu is one of the few states to generate more power than it needs and it already exports around 700 MW to neighbouring states. But during the windy months of May and June its export earnings are curtailed by lack of transmission. Under discussion is construction of a southern grid for the states of Tamil Nadu, Andhra Pradesh, Kerala and Karnataka. A task force of industry leaders, policy makers and experts is to identify the challenges faced by increasing wind energy generation and report back in three months.