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USA's power lines are fraying

By Fred Bayles USA TODAY

HERMANTOWN, Minn. -- Viewed from the air, this section of the nation's power grid bristles with electricity.

High-voltage towers form a 60-mile path to coal-fired generators churning out 1,000 megawatts -- enough electricity to run 200,000 homes. Other electric lines lead off to hydroelectric dams in Canada and power plants 400 miles west on North Dakota's coal fields.

The power lines converge here at Minnesota Power's Arrowhead substation outside Duluth. They form a picture of energy aplenty on the rolling plains of the northern Midwest that seems remote from rolling blackouts in California.

But 150 miles to the south, near St. Paul, lies a potential short in the circuit: the single high-voltage line linking Minnesota to Wisconsin.

If it fails -- as it did in 1998 during a thunderstorm -- the impact on the power grid could leave a swath of darkness from Winnipeg to Chicago. A plan to build a 250-mile backup line from the Arrowhead substation in Minnesota to Wausau, Wis., faces opposition that will take years to resolve.

There are other problems throughout the 157,810 miles of high-voltage wires, towers, transformers and substations that form North America's power grid. And as the national appetite for electricity grows, this aging system of transmission lines is fraying.

The power grid is being used in ways never envisioned when utilities began building it piecemeal more than 70 years ago. Once a series of modest byways that allowed neighboring power companies to exchange electricity in emergencies, the network has evolved into a system of highways moving big blocks of power sold at wholesale rates across regions of the country.

But the transmission capacity has failed to grow with the increased traffic of electricity. Construction of power lines has declined over the past 25 years at the same time more electricity has been added from new power plants. As a result, parts of the network are overtaxed to the point that transmission wires literally sag from the added electric flow.

''The system is getting tighter and tighter as time goes on,'' says William Hogan, an economist with Harvard University's Electricity Policy Group. ''Every place has different degrees of this situation.''

The problems are showing up around the country:

* Two of California's recent rolling blackouts were blamed on an electric traffic jam at what's called Path 15, a 90-mile corridor of two 500-kilovolt transmission lines that link the northern and southern sections of the state's power grid. There have been no additions to the wires since the 1960s.

When some power plants in northern California went off line in January, emergency power was needed from the southern part of the state. A bottleneck resulted along Path 15 because the lines couldn't carry the additional power.

* Past blackouts in New York pointed out a critical weakness. Incoming transmission lines can carry about half the electricity the city would need on the hottest days. There are proposals to build power plants in the metropolitan area, but there are no plans to build lines to upstate power plants.

* In sections of West Virginia and southwestern Virginia, demand for electricity has grown 135% since 1973, when the last transmission line was built to power plants on the Ohio River. The local utility, American Electric Power, proposed another line in 1991. But opposition and a complex regulatory process have delayed the project until 2004. The utility warns that without a backup, the failure of a critical transmission line could black out an area from Beckley, W.Va., to Roanoke, Va.

* Although the addition of power plants over the next five years will give Texas a surplus of electricity, there are only two high-voltage lines going out of the state. That leaves no easy way to ship excess power to neighboring states such as New Mexico and Arizona.

The nation's power grid is split into three divisions: Texas, all other states east of the Rocky Mountains, and all states west of the Rockies. Those are subdivided into 10 ''regional reliability councils'' that monitor the flow of electricity and coordinate steps to keep the lights on during emergencies. These councils were created after the 1965 blackout that left 30 million people in the Northeast and Canada in the dark for 13 hours.

The strategy worked for 30 years. But in the past five years, deregulation has encouraged utilities to buy and sell cheap power over long distances.

''With so many transactions today, we need the equivalent of a superhighway. What we have is a road with a lot of toll booths,'' says David Owens, a vice president with the Edison Electric Institute, a consortium of investor-owned utilities.

Deregulation produced a radical shift. In 1996, there were 25,000 individual sales of wholesale power between utilities. Last year it was more than 1 million.

This strain on power lines worries officials such as Minnesota Commerce Commissioner James Bernstein. In a report entitled ''Keeping the Lights On,'' his department warned that 2,000 more megawatts would be needed at peak times in seven Midwestern states by 2006. But the report also noted that the current amount of electricity flowing through the region ''has stretched the transmission system to its reliability limits.''

Plans for more transmission lines often face opposition from environmentalists and residents who don't want the looming towers and high-voltage lines because of fears about electromagnetic fields and the prospect of lower property values.

Deregulation of electric utilities in 24 states also has slowed the construction of transmission lines.

Some say incentives could alleviate the burden on the network. States such as New York, New Jersey, Pennsylvania and Maryland allow utilities to charge more for power if they locate generators near customers, taking the strain off transmission lines. And the demand for more electric pathways has attracted companies to the transmission business. TransEnergie U.S. Ltd., wants to lay high-voltage cables across Long Island Sound to link New England and New York utilities.

To encourage more construction, state officials such as Minnesota's Bernstein want to streamline the regulatory process.

''People want power, but they want power where they can't see it,'' he says. ''But if we're going to keep the lights on, we're going to have to make some tough choices.''

http://www.usatoday.com/usatonline/20010302/3108011s.htm

-- Martin Thompson (mthom1927@aol.com), March 02, 2001