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Washington blackout highlighted aging electrical grid

Friday, April 10, 2015 - 07:50

[WASHINGTON] The fact that a severed transmission line in Maryland could cut power to much of the nation's capital became the latest warning sign that the country's aging electrical grid can't meet modern demands.

Tuesday's widespread power outage came just weeks before the Department of Energy (DOE)is expected to release recommendations for modernizing the country's electricity infrastructure. The department recently spearheaded a 15-month review that examined the country's energy transmission, storage, and distribution infrastructure.

The US electrical grid, designed to serve far fewer people than it does today, faces a range of challenges that were unanticipated when it was built, including threats of cyber attacks, a need to incorporate power from renewable energy sources and the likelihood of more frequent and severe storms as a result of climate change.

Among the improvements the DOE may recommend are boosting the system's ability to store electricity for use at peak times, increasing the use of real-time data to respond faster to outages, and making the grid better able to operate seamlessly with a mix of conventional fuels such as natural gas and the more intermittent energy of renewables such as solar or wind.

All those changes would require massive - and expensive - upgrades of the existing transmission system. "All of our critical infrastructures are fragile," said Admiral Bill Gortney, head of US Northern Command.

Much of the backbone of the grid was designed in the 1950s, with 70 per cent of transmission lines and transformers now at least 25 years old, and 60 per cent of circuit breakers dating back about 30 years, according to a report by the National Governors Association. "If Thomas Edison came back and saw the electric grid, he would still recognise it," said Tom Willie, CEO of Blue Pillar, a company that manages backup energy systems for companies.

Much of the current system is too antiquated to take advantage of technologies that can make the grid more efficient.

Crucially, the grid needs to be able to adopt smart technologies that monitor demand fluctuations. It also must find ways to handle input from rooftop solar panels that let homeowners control personal energy use while selling excess power to the grid.

These changes all point to the need for a more de-centralised grid that would be better able to contain the impact of blows to any part of the system, many experts say.

"This grid is likely to evolve away from a centralised system to a hybrid of centralised and more localised controls," said Jeffrey Taft, chief architect for electric grid transformation at the Pacific Northwest National Laboratory. "One of the things being worked on now is a significant effort resulting from Superstorm Sandy to improve the resilience of the grid," he said.

That massive hurricane, which struck the Eastern Seaboard in October 2012, left more than 8 million customers in 17 states without power - more than 1 million of whom did not get service restored for a week or more.

The likely cause of Tuesday's blackout was less dramatic. Although regulators and Pepco, the regional utility, were still investigating the outage, indications are that the power loss was triggered when a 230-kilovolt transmission conductor broke off its support structure and fell, cutting off supply to the switching stations of a local Maryland utility.

This caused a dip in voltage that rippled across Pepco's service area. Government buildings were only without power momentarily, however, as emergency generators kicked in.

Gerry Cauley, president of the North American Electric Reliability Corporation, which monitors and oversees power transmission systems, said that while it was natural to worry about the impact on the nation's capital, the system, worked as it should have. "Sometimes I see a false sense of what the takeaway of such an event is - that the system is fragile," Mr Cauley said."Actually, the grid has many multiple redundant parts and is very robust." But despite its sturdiness, Mr Cauley acknowledged, parts of the grid require modernisation, and he said he expects the Energy Department review will "highlight opportunities," to make upgrades.

Melanie Kenderdine, head of policy at the Energy Department and leader of the study, said earlier this month that the review will deal with "transmission, storage and distribution structure," with "energy asset security" and with how to make the "transition to a low-carbon grid of the future." But Mr Cauley warned against expectations that a large-scale transformation of the grid will happen quickly, noting that it will involve complex permitting processes across every state. "I think we are in a continuous state of modernization of the grid - but there will not be an all-of-a-sudden transformation," he said.

REUTERS