Inadequate investment in the power grid transmission network remains the Achilles’ heel of the nation’s electric system, according to an engineer who specializes in utility policy at the University of Illinois (UI).

The electric industry and government regulators have addressed the immediate problems that led to the nation’s worst power failure on Aug. 14, 2003, said George Gross, UI professor of electrical and computer engineering. This includes mandatory reliability standards for the industry, which were passed by Congress as part of the 2005 Energy Policy Act.

But the broader problems of transmission congestion and bottlenecks continue to threaten the reliability of the grid, particularly during periods of peak demand.

“The August 2003 blackout was a wake-up call for the country to upgrade its transmission grid system,” Gross said. “But the truth is, very few major transmission projects have been constructed and, as a result, transmission capacity has failed to keep pace with the expansion of the power grid.”

The 2003 blackout prompted calls for spending of up to $100 billion to reduce bottlenecks and increase capacity of the transmission lines that carry electricity from power plants to homes and businesses.

Instead, investment has lagged behind power plant generation and growth in demand for electricity.

“Demand growth is forecasted to be 20 percent between 1998 and 2008, but the increase in transmission capacity is still below 5 percent,” said Gross. “The need to strengthen the existing transmission infrastructure, to expand it and to effectively harness advances in technology constitutes the single most pressing challenge for the country’s electricity system.”

Gross recommended the introduction of incentives to spur utilities and transmission companies to increase capacity. In addition, state regulatory agencies show more initiative in encouraging new power networks that cross state lines and serve a regional, rather than strictly local purpose.

A late July heat wave in California resulted in cutbacks in electricity use by government agencies and businesses to avoid the kind of rolling blackouts that plagued the state in 2000 and 2001.