US finds green energy is not exactly a lightbulb idea

Such carbon-reduction rules are already in place in 27 states and four Canadian provinces, and new ones could be mandated nationally in both countries. They may force changes in the utility industry, the group said, including the shutting down of coal plants that are located near load centres, and substituting power from wind turbines or solar plants in remote areas.

These actions would impose new demands on a transmission system that was never designed for large power transfers over extremely long distances.

The group also said that the carbon emission rules could increase reliance on natural gas, making power generation vulnerable to supply interruptions.

Carbon emission initiatives are the “No. 1 emerging issue” for the grid, according to Rick Sergel, president and chief executive of the group, which is based in Princeton. Renewable energy can form a larger portion of electricity supplies without reducing reliability, Sergel said, but not without investments in transmission.

The overhauled electric system that had emerged in the last two decades already had inadequate transmission capacity, he said. Independent power producers have built generating stations that compete in a geographically vast marketplace to serve distant consumers. “The transmission system is being used closer to its limits more of the time than at any time in the past,” Sergel said. The report was based on information from 50 utilities, power generators and other electric system participants.