Planning is underway to upgrade the often-constrained transmission path which carries electricity between northern and southern California, the chief operating officer of the California Independent System Operator (ISO) said during a Tuesday briefing.
Kellan Fluckiger said the ISO and Pacific Gas & Electric Co. have been working for some time on a proposed upgrade plan, including a 500 kv line, which should be "completed in the next few days." Fluckiger described the proposal on a day the direct current (DC) transmission path was operating at 50% capacity, sharply reducing the amount of electricity that could be shipped North on the eighth day of threatened rolling blackouts.
Fluckiger said actual construction on a upgrade is still some time away, noting a new transmission line will require lengthy environmental hearings and potential acquisition of right-of-way. The proposed line will require "big towers and large footprint," he said. More transmission capacity is desperately needed, he said, in addition to 10,000 more megawatts during the next 3-4 years.
The grid operator flirted with ordering rolling blackouts in northern California off and on Tuesday morning. Fluckiger said supplies are so tight the decision is being made on an hourly basis. During the morning hours, the ISO was able to import 1,000 Mw from Canada and will get the power again tonight to help the state get over the evening peak. However, it is not available during the early afternoon, and the ISO can no longer call on interruptible customers to cut power.
Under the program's guidelines, customers can be asked to reduce usage 30 times/year or 100 hr/year. In exchange for being the first to have their power curtailed during shortages, these customers receive a discounted rate.
Pacific Gas & Electric Co. said it 2001 interruptible customer program (north of Kern County) has been exhausted. The California utility has about 170 commercial and industrial customers representing 400 Mw who voluntarily signed contracts to participate in the program.
With some 7,300 Mw of generating capacity still offline for scheduled maintenance or forced outages, the interruptible load customers often made the difference between calling for rotating outages or not.
"We do the dance as best we can, and then we make a decision," Fluckiger said.
The state has now stepped in to buy power on behalf of Pacific Gas & Electric and Southern California Edison Co. Fluckiger said the state covered about 90% of the $46 million in power purchases made Monday. Friday the Legislature appropriated $400 million for power purchases as a stopgap measure, while lawmakers struggle to come up with a long-term solution to the state's power woes.
Fluckiger said the ISO has asked the US Energy Department to extend an order forcing out-of-state power producers and marketers to sell excess electricity into California. But it has not received a reply. Bush Administration energy officials met Monday to discuss what, if any, response should be made by the federal government.
