Failures in medium-voltage power cables and their components cause a large proportion of annual power service interruptions, especially in high-density urban areas. Locating and repairing weak...
Reliability demands will drive automation investments.
In the days and weeks following Aug. 14, 2003, politicians scrambled to assess blame for the blackouts that plagued the United States and Canada.
Even today, as the blame game proceeds, the precise cause of the grid's collapse remains uncertain. But Republicans, Democrats, and the utility industry alike seem to agree on one thing: the U.S. power grid needs major investment.
"We need between $50 billion and $100 billion over several years to upgrade the nation's transmission system," said Kurt Yeager, president and CEO of the Electric Power Research Institute (EPRI) in Palo Alto, Calif.
Despite pressures to enhance grid reliability, mobilizing $50 billion to $100 billion for transmission system investment seems like a Herculean task. Faced with regulatory uncertainty and economic malaise, utilities are not well positioned to make such colossal infrastructure investments.
"I suspect I'll have a lot of questions from our clients, saying, 'They want us to invest money in technology to increase reliability, but nobody is giving us the money to do it,'" says Jill Feblowitz, research director with Boston-based AMR Research.
Policy questions aside, the big challenge for the industry in the coming months and years will be figuring out how to improve grid reliability and survivability-without accumulating a Herculean tab.
Weaknesses in the power grid can be narrowed to two general areas-transmission capacity and network control systems. Both of these areas will likely see increased investment in the years to come, but the precise focus of such investments remains to be determined.
Just nine days before the East Coast blackout, EPRI released a report titled Electricity Sector Framework for the Future, resulting from a series of workshops and analyses on the challenges facing the power industry. The report logically emphasized the policy and market barriers that impede the industry's progress, but it also set forth a technological vision-de-force for the power grid.
Specifically, EPRI envisions:
- Digital network control: Real-time, electronic controls would replace the system's existing electromechanical switchgear, enabling faster and more seamless control of the network.
- Integrated power and communications: Merging the power grid with communications networks would create a "dynamic, interactive power system" that would support the real-time exchange of information and power.
- Enhanced meters: Replacing the old metering system with real-time, two-way energy information systems would allow price signals, market information and buyer decisions to flow freely.
- Distributed resources: Incorporating distributed generation sources would improve system reliability and capacity.
- End-use efficiency: Technology advances would raise the efficiency of end-use devices, and improve utilities' ability to control those devices.
Automation comprises the core of EPRI's technology vision. "From our view, the grid has to become more automated," says Luther Dow, director of power delivery and markets at EPRI. "We need to invest more in information technology and new, smarter equipment."
An example of such equipment is FACTS (Flexible AC Transmission Systems) technology, which uses silicon-controlled rectifiers (also called "thyristors")-small, semiconductor-based controllers that can route large power flows much faster than is possible with the electromechanical switches that have dominated the grid's operation for decades.