The transmission team plans for peak hours, or when maximum demand will occur on the system. Incorporating assumptions about what the generation and load will be during peak hours in a transmission planner’s model runs into problems when, for example, 4,000 MW of wind power to which the resource planning team had given a capacity rating of 600 MW generates at full capacity.The solution, spend more money, much more money than the cost of the windmills, to upgrade the transmission grid.
“When I plan a transmission system that’s capable of 600 MW firm, what do I do with the other 3,400 MW if it shows up?” Bradish said. “It’s happening now and is causing issues on our transmission grid.”
This is making planning that used to be relatively routine more complex, said Chuck Liebold, PJM’s manager of interregional planning.
“PJM is now recommending transmission upgrades due to light load criteria, which looks at a 50% peak load and is heavily influenced by renewables integration,” Liebold said.
Monday, December 12, 2011
Wind power constipates the Midwest grid
Another unintended consequence of wind power, the Midwest electric grid cannot transmit all the wind generated power when the wind blows hard. Reported by Energy Central: