High Temps Bring Energy Worries

High heat and increasing humidity are expected to continue to scald Southern California on Tuesday, bringing temperatures as high as 116 in the low deserts and possibly straining the region's energy supplies.

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Both Southern California Edison and the Los Angeles Department of Water and Power, which supplies electricity to the city of L.A., have said that they believe they have access to enough energy to meet the region’s needs.

But a prolonged heat wave could challenge assumptions about how much energy is needed to keep Southern California homes and offices running smoothly. In a worst-case scenario, aging equipment could become overloaded, or - less likely - energy supplies could fall short.

With the massive San Onofre nuclear power plant likely to be shuttered for at least another several months, and aging infrastructure in DWP territory in need of upgrades, officials at both utilities are asking consumers to cut back their energy usage during the anticipated heat wave.

“Multiple days of high temperatures where the temperatures stay high at night are what can cause problems in Southern California,” said DWP spokesman Joe Ramallo.

This summer's heat brings concerns about the sheer volume of energy that will be available - as well as the cost.

Southern California Edison's San Onofre Nuclear Generating Station typically provides up to 2,200 megawatts per day of power - a tenth of that used in the giant for-profit utility's territory on a hot day.

But the plant has been closed since the beginning of the year because of excessive wear in steam tubes and other maintenance issues. It is not likely to re-open for months, if at all.

Peak usage during hottest period of August last year was just under 21,000 megawatts in SoCal Edison territory; during the hottest part of July this year, the peak was a little less, hitting just under 20,000 megawatts, spokesman Darryl Ryan said Tuesday.

Edison met that need by planning in advance to buy outside energy during the hot summer period while the San Onofre plant remains closed, Ryan said. In Los Angeles, the city was on track to use an estimated 5500 megawatts of power on Tuesday, an amount the utility believes it will be able to provide.

Of greater concern, Ramallo said, was overloading the region's infrastructure with days and nights of unabated heat.

The last time that happened was in 2006, when blackouts afflicted tens of thousands of customers of both utilities as persistent heat prompted people to use their air conditioners at night as well as during the day.

As a result, equipment that was never intended to carry the load of electricity used by modern homes and neighborhoods overloaded. Edison and DWP were forced to replace hundreds of transformers on the spot, and residents suffered for days without power.

Much of the old equipment has been replaced since then, but that doesn’t mean that prolonged, intense usage won’t cause some to overheat, Ramallo said.

Both of the giant utilities are urging consumers to cut back energy use as the heat wave builds.

Among other measures, they are asking people to set their air-conditioning thermostats to 78 degrees, and switch to open windows and electrical fans whenever possible.

The high temperatures are expected to continue until the weekend. Ontario is expected to max out at 107 Tuesday, and the temperature in Woodland Hills is forecast to hit 102.

An excessive heat watch is in effect for Los Angeles County through Friday evening. An excessive heat warning for Riverside County is expected to last until 8 p.m. Wednesday.

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