Southern California was struck with a new round of power outages Monday as demand for electricity stretched the state's supply and the aging system of local lines and transformers continued to fail in the face of a record heat wave.
The demand for electricity was so great that California's power regulators asked some businesses to cut back their power usage. The state narrowly avoiding rolling blackouts as temperatures moderated slightly -- a cooling trend expected to continue today.
For The Record
Los Angeles Times Thursday July 27, 2006 Home Edition Main News Part A Page 2 National Desk 1 inches; 63 words Type of Material: Correction
Power transmission: A graphic in Tuesday's Section A about the role of transformers in distributing power to homes referred to current being stepped up to hundreds of thousands of volts on its way from the generating plant to a receiving station. The voltage is stepped up in that process. Current is measured in amperes, not volts, and it is reduced in that process.
Officials were more immediately concerned about the nearly 1,000 transformers atop power poles and in underground vaults that have been overwhelmed in recent days, leaving thousands without electricity.
Both the Los Angeles Department of Water and Power and Southern California Edison acknowledged Monday that their systems -- parts of which were built in the 1920s and 1930s -- were not designed to handle anywhere near the power demand produced during the heat wave.
Many older transformers are too small to carry the loads put on them by modern households, said DWP General Manager Ron Deaton.
"When these transformers were installed, you had neighborhoods that weren't air-conditioned, homes without two computers and five television sets," he said.
City officials said they have been trying to replace the older transformers for years but have made only modest progress because of limited funding.
Los Angeles has about 126,000 pole-top and underground transformers. About 150 have been replaced and 274 repaired during the heat wave.
Councilman Greig Smith estimated that most of the city's transformers are already at or near capacity. It's unclear how many need to be replaced, a question Smith hopes the DWP can answer at today's City Council meeting.
One concern now is a shortage of new pole transformers statewide because so many have overheated over the last few weeks. But in the wake of the blackouts, several City Council members said they would push to replace the aging transformers more quickly.
"We have a situation of urgency," said Councilwoman Jan Perry. "Clearly, the population has outweighed the city's infrastructure."
As of Monday afternoon, there were still 10,000 customers in the San Fernando Valley and 5,600 customers in the rest of Los Angeles without power. An additional 17,000 customers in territories covered by Edison -- including the South Bay, the San Gabriel Valley and Orange County -- were without electricity.
The DWP had 91 crews in the field Monday replacing transformers and overhead and underground power lines, including repair crews brought in from the Owens Valley and Utah. Some neighborhoods have been without power for more than a day.
Henry Martinez, the head of the DWP's power system, said the utility was hoping to restore all power within the next 24 hours.
"We've got crews out there, and they are running from site to site," he said.
While many families continued to go without power on Monday, the ordeal ended for some.
The power came back on at Desiree Causey's Westminster house at 2 a.m. Monday, after nearly two days.
Causey said she had to throw out $400 worth of food in her refrigerator.
"It's been pretty miserable," she said. "I've got a husband, two kids, and two hot dogs. We've spent a lot of time in our pool."
Since July 13, when the high heat began, 765,000 Edison customers have lost power due to heat, wind or lightning strikes, the utility said.
Officials said the hot weather has underscored the age and vulnerability of the region's electricity transmission system.
Since the heat wave began, Edison has had to replace more than 715 transformers, spokesman Steven Conroy said. Transformers are crucial equipment that reduce the flow of electricity so that it is safe for use in homes and businesses.
Some were overwhelmed because of their age, Conroy said. Many of the company's poles, wires, transformers and other equipment are more than 40 years old.
But others shut down because they were simply not built to carry the electricity demanded by customers during the heat wave, Conroy said. In June and thus far through July, Edison customers have used 18% more power than during the same period last year, he said.
Edison officials said they hope to make fixes as part of a $9-billion infrastructure upgrade over the next five years.
The DWP increased its budget for infrastructure maintenance and upgrades by more than $75 million this year, including $3.5 million to replace pole-top transformers.
"Obviously, we are continuing to maintain our system," Mayor Antonio Villaraigosa said. "We may have to more aggressively do so."
The DWP has about 200 new transformers in its warehouses and is expecting 150 more in September, city officials said. The transformers cost $1,500 or more, depending on their size. Most pole-top transformers are gray or black cylindrical metal structures that are 3 or 4 feet high and weigh about 300 pounds.