SOUTHLAND HEAT WAVE Heat
Stretches California Power Network to the Limit
The state barely avoids rolling
blackouts, but unplanned outages occur anew as
crews labor to fix old and overloaded equipment.
by Sharon Bernstein, Patrick McGreevy and Marc
Lifsher, LA Times Staff Writers July 25, 2006
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: 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
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
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,"
City officials said they have been trying to
replace the older transformers for years but have
made only modest progress because of limited
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
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
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
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
"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.
But the DWP's Martinez noted that with
transformers going out all over the West, the
supply of replacements is running thin.
"We have gone through the stock," he said. "We
have ordered more … but we've got to get our stock
back up. That's going to be a critical aspect in
getting customers back in service."
If the heat continues, more equipment is likely to
fail, he said.
The question of capacity goes to the heart of why
the system was overwhelmed in some areas but not
For example, Edison routinely supplies more power
to homes and businesses in areas that typically
have the highest summer temperatures, such as the
high desert and Palm Springs. By way of example,
Conroy compared underground transformers used in
Palm Springs and Santa Monica. Although both carry
the same amount of electricity, the Palm Springs
transformers are wired to serve just six
households each, while those in Santa Monica serve
The situation is similar in non-desert areas
throughout the region — even hot climates like the
Inland Empire and the San Gabriel Valley, where
many of the week's outages took place. Conroy said
it would be too expensive to use additional
transformers or larger ones.
Though temperatures are dipping slightly, the heat
continues to cause numerous problems.
Statewide, power usage neared maximum capacity
Monday, and Gov. Arnold Schwarzenegger directed
state agencies to reduce electricity use by 25%
and turn off unnecessary equipment. He urged local
and municipal governments and universities to do
The heat wave is the worst since 1998 statewide
and has been so intense that the demand for
electricity is up 40% compared with the state's
energy crisis of 2001, Cal-ISO Chief Executive
Yakout Mansour said.
Heat is at levels expected only once every 50
years in some parts of the state and once every
100 years in others, said Joseph Desmond, deputy
secretary for energy at the California Resources
Four deaths in Southern California over the
weekend were linked to the heat, mostly in
outlying portions of San Bernardino and Riverside
counties. In the Central Valley, 13 deaths have
been blamed on the heat, including two men who
died on a front lawn in Fresno.
Meanwhile, officials were investigating a Stockton
nursing home after a patient died when the air
conditioner gave out in the 115-degree weather.
They also were looking into the death of a
gardener who collapsed on the job in Bakersfield.
No deaths were reported in Los Angeles County. But
the heat appears to have caused an increase in
ambulance calls, said L.A. Fire Chief William
Bamattre. On an average day, crews respond to
about 1,000 medical and fire calls, but Bamattre
said his agency received about 1,500 calls on
Saturday and more than 1,200 on Sunday.
Times staff writers Susannah Rosenblatt, Andrew
Blankstein, Dave McKibben, Ashley Powers, Ashley
Surdin and Hector Becerra contributed to this
Power to the home
Old transformers that weren't designed to handle
the demands of modern homes during a heat wave are
a weak link in the power distribution system.
How transformers work
- Transformer drums on power poles (or green
transformer boxes attached to underground lines)
reduce high voltage running through power lines to
lower levels for household use.
- In Southern California, parts of the power
distribution system date to the 1920s and 1930s.
- Inside the transformer, higher voltage
electricity in a tightly wound set of coils is
transferred to output wires with fewer coils.
Fewer coils means less voltage.
How we get electricity
- Generating plants are powered by fossil fuels,
water, nuclear power, wind and solar energy.
- The current from the plant is stepped up to
between 220,000 and 500,000 volts on its way to a
receiving station, to reduce energy loss on its
journey over long distances.
- Voltage is reduced as it passes through
distribution stations, substations and
transformers on the way to homes and businesses.
Sources: HowStuffWorks. Graphics reporting by
Cheryl Brownstein Santiago
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