Exclusive: Warm winter temperatures slammed California wind farms 

Wind energy deliveries to California’s top utility fell by half in the first two months of the year because of unusually weak winds in some Western states. The slowed wind energy production has exacerbated electricity shortfalls caused by a long drought, which has reduced hydroelectric power in the most populous U.S. state.

Southern California Edison, which is owned by Edison International, said that any gaps left by the 50% drop in wind production during an exceptionally warm January and February will be filled with electricity bought on the open market. Spot purchases tend to be more expensive and often come from natural gas.

The one-two punch of exceptional dryness and diminished winds comes as California aims to source 33 percent of its electricity from renewable sources by 2020, a goal Gov. Jerry Brown wants to raise to 50 percent a decade after that.

The state currently gets about 7 percent of its electricity from wind projects inside and outside California and 25 percent from renewables, which include solar. California is the No. 2 U.S. producer of wind energy, with 5,914 megawatts of capacity.

Despite the lower wind production, Socal Edison said it would still be able to meet the state’s renewables goal over the long term.

San Diego Gas & Electric, another of the state’s big three investor-owned utilities, said its wind deliveries are down 10 percent from last year. The Sempra Energy-owned utility has been able to make up for a significant shortfall from nearby wind projects by importing more electricity from wind farms in Montana.

The utility said that because of the intermittent nature of renewable energy, it must have backup resources available. Most of the time that replacement electricity comes from natural gas powered plants.

PG&E Corp’s Pacific Gas & Electric said January wind production was lower than forecast, but that it had not experienced overall poor production through the first quarter.

LOWER WIND SPEEDS

Wind speeds west of the Rocky Mountains were at least 20 percent below average in January, and in some places down nearly 50 percent, according to weather forecasting firm Vaisala. They recovered somewhat in February, though were still low, and worsened again in March.

In fact, the Southern and Western United States, including California and Texas, experienced its worst first quarter for windiness since record-keeping began 47 years ago, according to Pascal Storck, global manager of energy services for Helsinki-based Vaisala.

“If you own a wind farm, you are praying for wind,” Storck said in an interview. He said periods of low wind can last two or three years, but that it is too soon to say how long this lack of wind will last. He also said it would be premature to link the weak winds to the drought, which started much earlier.

Contracts between wind farm operators and utilities typically provide for variations in production of between 70 percent and 120 percent of normal, according to Nancy Rader, executive director of the California Wind Energy Association.

“We’re not out of that range,” Rader said.

Wind farm owners contacted by Reuters either declined to give production statistics for their projects or did not respond to queries.

But Pattern Energy Group Inc, which owns several wind farms in Texas, California and elsewhere, said in a statement earlier this month that it had cut its annual expected wind production outlook by 5 percent because of slower winds.

Texas, the No. 1 wind power producer, saw a 14 percent decline in wind power output in the first quarter, according to megawatt hours data from grid operator ERCOT.

About 10 percent of power in Texas comes from wind and, like California, it is adding wind farm capacity. On Feb. 19, Texas hit a record high for instantaneous wind output of 11,154 megawatts.

(Reporting By Nichola Groom; Editing and additional reporting by Terry Wade)