Cost per Unit
million 500 $5,460
million 967 $2,850
million 2,040 $1,450
million 5,000 $1,320
you’re going 500 miles, then you’ve got
significantly lower power losses on the
line. This makes DC a more cost-effective investment,” Detweiler said.
A 765-kV line has 10 times the capacity of a 230-kV line and about one-fourth its cost per
unit of capacity. Image courtesy of Edison Foundation, AEP.
Note: Approximate relationship based on surge impedance loading (i.e., reactive power
Resolving Wind Power’s
One of the major differences between
wind power generation and other forms
of energy generation is that wind power
is variable. This challenge can be well-managed via an extensive and robust
transmission line network, Detweiler
“One of the advantages of a DC system is that you get a lot of control as
a result of converting back and forth
from AC to DC,” Detweiler said. “So, big
picture, with wind and solar energy resources’ variability, the best way to integrate large volumes of renewables is
Transmission Lines in Progress
The Obama administration says it will speed approval for seven transmission projects in 12 states in an effort to connect renewable energy to load centers,
spur infrastructure building, and modernize the U.S. grid.
Together, the projects will cost more than $8.5 billion,
according to a Bloomberg report. At least five of them will
transport renewable energy.
called TransWest Express is being developed by billionaire
Philip Anschutz that would connect energy from a 2,500-
MW wind farm his company is building in south-central Wyoming to Southern California, Nevada, Arizona, Colorado, and
way transmission line, part of the Idaho Power transmission
line, would ship hydropower and wind power, as well as electricity generated from coal and natural gas-fired power, between Boardman, Ore., and Melba, Idaho.
• The $825 million, 500-kV, 210-mile-long Cascade
Crossing project being developed by Portland General Elec-
tric Co. would ship power to populated areas in western Or-
egon from wind farms in the eastern part of the state and
from gas-fired power plants that might be built to replace
power from the Boardman coal plant, which Portland General
plans to shut down in 2020.
Sources: White House press releases and Dow Jones Newswire