Transmission grid upgrades by the California Independent System Operator (CaISO) have significantly reduced costs associated with local bottlenecks with congenstion costs falling by 58% from $205 million in the first seven months of 2004, to $87 million for the same period this year.

Cost are calculated as re-despatch costs that occur when transmission constraints prevent energy from flowing as planned.

The upgrades include a series of three projects that, together, increased transmission capacity into Southern California by 1 GW. Yakout Mansour, president and chief executive of CaISO said: “Strategically planned transmission upgrades to the grid can be very cost effective.”