On anniversary of big blackout, study finds harsh weather plaguing U.S. grid

REUTERS/NOAA
Images taken by a National Oceanic and Atmospheric Administration satellite showing light coverage in the northeastern United States at 9:21 p.m. Eastern time on August 13, 2003, left, and after a massive blackout affected much of the area, right, shown at 9:03 p.m. Eastern time on August 14.

Today marks the 10th anniversary of the vast northeastern blackout of 2003, a cascading series of power failures that began with a heat-softened, sagging powerline near Cleveland and eventually left 50 million people from Michigan to Ontario to Massachusetts without lights, air conditioning or reality TV.

It was the worst blackout in U.S. history (and second-worst in the world’s), and it created a political climate that made possible the strengthening of certain federal reliability requirements and operating rules that govern the American power grid’s remarkably decentralized array of independent operators, most of them privately owned and overseen by state agencies.

But the grid has plenty of other problems, as a report issued Monday by the U.S. Department of Energy and White House Council of Economic Advisers makes plain. Below the level of long-distance transmission lines and regional coordination, which have been relatively trouble-free since August 2003, aging infrastucture and worsening weather patterns are driving some unhappy trends:

  • Severe weather events now cause nearly 90 percent of the nation’s “widespread” power outages, defined as those affecting at least 50,000 customers. (Weather also causes 58 percent of all outages tracked by the Energy Department.)
  • These large, weather-driven outages have been occurring at a steadily rising pace, and numbered 679 over the last 10 years.
  • The patterns of weather causation are a significant change from the decade immediately preceding. Through most of the 1990s (and for a couple of years in the early 2000s as well) weather caused significantly fewer outages than such non-weather factors as equipment failures, operator errors, circuit overload (and intentional “load shedding” to avert or contain overloads).
  • Large outages’ estimated cost to the economy — as measured in lost production and wages, spoilage, and damage to the grid itself —  can vary dramatically from year to year, depending on methodology and the severity of events themselves. But even the lower-end numbers are large: $18 billion to $33 billion per year, on average, according to Energy Department calculations, which adjusted the values for inflation; $25 billion to $70 billion, according to a study done last year by the Congressional Research Service.
  • And, of course, the largest weather-caused outages can be not only massively expensive and inconvenient but deadly. Fatalities associated with Superstorm Sandy stand at 159, according to the report, with 72 caused directly by the storm and 87 more attributed to indirect causes—of which 50 resulted from hypothermia, carbon-monoxide poisoning from unvented generators and heaters, and other consequences of lost power.

Severe weather, aging grid

Many factors are diving these unfortunate trends, but two in particular — worsening weather associated with climate change, and an aging power grid — are the most significant.

On the weather side, the frequency of severe events is clearly rising. Any number of measures have shown this, including the annual “billion-dollar list” of U.S. storms where losses exceed $1 billion.

Last year’s losses were among the worst on record, but they continued a trend that has been apparent for some time: as the report notes, seven of the 10 costliest storms in U.S. history have occurred since 2004.

Meanwhile, work to expand the nation’s power grid or improve its reliability is “well below the rates experienced between 1960 and 1990.” As a result, “70 percent of the grid’s transmission lines and power transformers are now over 25 years old and the average age of power plants is over 30 years.”

On the bright side, construction spending on the grid has actually risen somewhat in the last five years or so, despite flat or falling demand for electricity. This is expected to continue into 2015, the report says, in part because of $4.5 billion in federal economic stimulus funds allocated in 2009 to various grid upgrades: advanced sensors, digitized controls for distribution projects, “smart meters” and storage mechanisms.

Not a transmission problem

But this money is a drop in the bucket, and the nature of these special projects shows why: Although discussion of the grid’s modernization needs often centers on disputes over whether big new transmission lines are needed, or where they should be routed, most of the grid’s vulnerability lies downstream.

Drawing on data from the Edison Electric Institute, the report says that “although transmission system outages do occur, roughly 90 percent of all outages occur along distribution system” — that is, at or below the substation level, where weather-hardening needs are endless and the options both limited and expensive:

Placing utility lines underground eliminates the distribution system’s susceptibility to wind damage, lightning, and vegetation contact. However, underground utility lines present significant challenges, including additional repair time and much higher installation and repair costs. Burying overhead wires costs between $500,000 and $2 million per mile, plus expenses  for coolants and pumping stations. Perhaps the most important issue for coastal regions is that underground wires are more vulnerable to damage from storm surge flooding than overhead wires.

Common hardening activities to protect against flood damage include elevating substations and relocating facilities to areas less prone to flooding. Unlike petroleum facilities, distributed utility T&D [transmission and distribution] assets are not usually protected by berms or levees. Replacing a T&D facility is far less expensive than building and maintaining flood protection. Other common hardening activities include strengthening existing buildings that contain vulnerable equipment, and moving equipment to upper floors where it will not be damaged in the event of a flood.

Although distributing power generation may seem to multiply its vulnerabilities, by creating more sites to be “hardened,” the report does advance the notion of “microgrids” in which power is distributed at smaller scales, from locations scattered over larger areas, as a way of increasing the overall system’s flexibility and robustness:

A key feature of a microgrid is its ability during a utility grid disturbance to separate and isolate itself from the utility seamlessly with little or no disruption to the loads within the microgrid. Then, when the utility grid returns to normal, the microgrid automatically resynchronizes and reconnects itself to the grid in an equally seamless fashion. Technologies include advanced communication and controls, building controls, and distributed generation, including combined heat and power which demonstrated its potential by keeping on light and heat at several institutions following Superstorm Sandy.

If $4.5 billion is a drop in the bucket, how deep is the bucket? For all its detailed examination of costs associated with power outages, the report stops short of laying out an specific overall strategy for preventing them, or estimating costs for the multiple approaches it says should considered.

However, the Los Angeles Times obtained a figure from the American Society of Civil Engineers, which

estimated that $673 billion in investments would be needed by 2020 to upgrade the grid to meet future demand. But the costs of such improvements are recouped through rate increases, often unpopular moves that must be ratified by state regulators.

The Times also reported that

Electric utilities have invested $478 billion in infrastructure improvements since 2007 and are expected to spend more than $90 billion annually on capital projects through 2015, said Richard McMahon, vice president of energy supply and finance at the Edison Electric Institute, a Washington trade group.

You can also learn about all our free newsletter options.

No comments yet

Leave a Reply