Concerns Raised About Changes To Grid If Yankee Closes
07/20/10 7:34AM By John Dillon  Download MP3
(Host) The company that controls Vermont's transmission network is concerned about the reliability of the New England power grid if Vermont Yankee is shut down.
The Vermont Electric Power Company has asked for a study of how the system will be affected if Yankee goes off line when its license expires in 2102.
VPR's John Dillon reports:
(Dillon) Utilities will have to buy replacement power if Vermont Yankee is retired on schedule in 2012. But utility officials are worried about another potential cost as well. The 620 megawatts that the nuclear plant pumps into the regional grid keeps the system in balance.
What happens to the electricity grid when that much generation is removed? Would the system become less stable, and more prone to failures or blackouts? These are the questions the Vermont Electric Power Company is asking. The company owns the state's bulk transmission lines. Christopher Dutton is C-E-O.
(Dutton) "The study is designed to look at the system with Vermont Yankee no longer available. It's designed to find out or identify how many hours of a given year and at what level of load the system is confronted with problems."
(Dillon) The reliability study is being conducted by ISO New England, the independent system operator that controls New England's wholesale electricity market. Vermont Yankee has operated without much interruption for many years. But the Legislature has so far refused to extend the plant's license. Dutton said the uncertainty over Yankee's future prompted ISO New England to look at what would happen if the nuclear plant goes off line.
(Dutton) "It was only, I would say, in the last eight months to a year when the politics have started to indicate that there was doubt, some real doubt, about the plant's license extension beyond 2012 that they've come to conclude that perhaps we ought to be doing some planning now to reflect the uncertainty associated with re-licensing."
(Dillon) The physics of the electric grid require a constant balance between the amount of power being used and the electricity being generated.
Now, power planners are concerned that the loss of a major generation source like Vermont Yankee could have an impact throughout the region.
Marcia Blomberg is a spokeswoman for ISO New England.
(Blomberg) "The larger the generator and the more efficient it is the greater the potential concerns could be with reliability. But there are also solutions and they could include transmission upgrades, private developers could build new generation, and energy efficiency could also be among the possible answers."
(Dillon) The study will look at various options, including how much new generation may be required to keep the system operating reliably.
The study should be completed by the end of the year.
For VPR News, I'm John Dillon in Montpelier.