The Federal Energy Regulatory Commission approved a final rule June 21 removing barriers to more renewable energy generation on the electric transmission grid. The rule requires transmission providers to offer electric generators the option of scheduling transmission service at 15-minute intervals, and generating companies using variable energy resources must provide transmission owners with forecasting data. The rule, which will take effect in twelve months, contends that renewable energy sources are exposed to excessive imbalance service charges because they cannot adjust their generation to comply with current hourly schedules.