Vermont News Briefs

Vermont Yankee losing backup power provider; seeks to build generator

Vermont Yankee’s parent company wants to build an onsite generator at the nuclear power plant site to produce electrical power in case of a station blackout.

In mid November, representatives of Entergy Nuclear Operations Inc., which owns and runs Vermont Yankee, met with Nuclear Regulatory Commission officials at the agency’s headquarters in Rockville, Md., to discuss Entergy’s planned application to amend the Vermont Yankee license to allow it to build the generator.

The nuclear plant currently draws power from the Vernon Hydroelectric Station just down the Connecticut River during such situations, but that will no longer be possible come September 2013.

ISO New England, the region’s energy marketplace, and TransCanada, which runs the Vernon station, are not renewing an agreement for the plant to provide power during blackouts, according to NRC documents. The contract is set to expire on Sept. 1 , 2013, and TransCanada is unwilling to enter into an agreement with Entergy to supply power.

The NRC writes that although the hydrostation won’t formally be credited as Vermont Yankee’s power source, the “tie line will remain continuously energized … and will be available to provide power to VY.” Furthermore, there are agreements in place to ensure that Vermont Yankee gets power from Vernon Power Station if needed.

NRC spokesman Neil Sheehan said regulators would monitor the situation closely and are waiting for necessary responses to the questions they asked.

“We posed several questions to Entergy regarding the new diesel generator that will have to be answered,” he said. “These include the timeframe for the state’s review of the plan and what happens if the state has not approved it at the time the Vernon hydro plant is no longer allowed as a credited (station blackout) source.”

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Andrew Stein

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  • This makes sense, even if tacking on to VY seems like a step in the wrong direction. There is good reason for Entergy to be thinking ahead by bolstering their backup power capacity. The entire grid itself may be just as prone to meltdown as our beloved plant on the Connecticut, so why not make it more disaster proof by generating on site. Can portable units be installed so that when VY does shut down, the (hopefully) lightly used diesel units can be repurposed? What about a number of portable natural gas microturbines that could be efficiently powered by trucked in NG and repurposed elsewhere after the decommissioning?

  • James Leas

    State regulators must immediately question TransCanada and Entergy under oath.

    Why is TransCanada refusing to allow its hydro plant to continue to provide power to Vermont Yankee in the event of a station blackout?

    What does TransCanada know? What is the concern?

    Is TransCanada realizing that they may face a liability in such a situation?

    It was the failure of diesel generator backup power after the station blackout that caused the meltdown at the identical type of reactor in Fukushima.

    Is TransCanada concerned about liability from an agreement with Entergy if a station blackout were to happen at Vermont Yankee, as happened in Fukushima?

    If TransCanada has a problem with Entergy then Vermont has a problem with Entergy. The state regulators should not permit any new construction at Vermont Yankee if Entergy gave TransCanada a reason to withdraw its backup power or if Entergy otherwise lost the complete confidence of TransCanada.

    As a first step Vermonters have a right to demand that both TransCanada and Entergy immediately receive subpoenas to have executives testify under oath and be thoroughly questioned to reveal to the public all the facts about the withdrawal of TransCanada.

    Provision for station blackout backup power is too serious a matter to allow executives at both of these corporate entities to avoid testimony under oath and the full personal liability that entails.

  • Bob Zeliff

    I think James Leas is on the right track.

    While the original article is not clear, I believe the back up power that they are talking about is NOT power for VY customers but power to keep minimal operations of VY so it remains safe.

    Since the tragedy in Japan due to lose of back up power, sources for it are realized to be much more critical to plant safety.

    Certainly the public has a right to know the full details of “new” VY problem.

    • Andrew Stein

      Dear Bob,

      The power is for Vermont Yankee in the event the station blacks out.


  • Matt/James,

    Vermont Yankee already has 2 diesel-generator sets for back up power, i.e., to keep certain critical equipment running during an outage, such as the 3-week maintenance outage every 500 days.

    ADDITIONAL, i.e., redundant, back up is the hydro power of TransCanada.

    This back up will end, because TransCanada’s contract with Entergy will end, and because TransCanada opted not to renew the contract. If not the lay public, this has been known to Entergy, the NRC, and the VT-DPS for some months.

    Entergy will be installing a third D/G set with its own tank to supplant TransCanada energy.

    BTW, major building complexes, such as medical centers, IBM, airports, etc., ALL have such D/G sets for critical functions.

    D/G sets are the preferred equipment for this service for various technical and operational reasons, well known to experienced engineers.

    • Bob Zeliff

      Often in safety critical circumstances, possible at the level of no single failure, can cause an unsafe condition, something like a local back up generator is used. In more critical application where no two failure will cause and unsafe condition another generator, at a diverse location, ie vernon hydro, would also be used.
      It is not clear on first look that adding another generator to the VY facility meet the possible diverse location safety criteria.

      I have to think of the recent NYC storm disaster were a major hospital lost BOTH of its diesel generators and all patients had to be removed.

      I don’t know the rules….just speculating

  • James Leas

    “TransCanada opted not to renew the contract” is the sole issue. All the questions posed in my comment above remain. The issue is not about replacement, and we should not be diverted into that discussion.

    The fact that TransCanada refuses to contract with Entergy raises red flags.

    The public has a right to the testimony under oath from executives at both companies.

  • Jim Barrett

    TransCanada must be required to answer WHY they have decided to opt out . My first thoughts are solely about the politicians who have directed the closing of VTY and I think encouraged other power companies to stop buying power from VTY. I think a strangulation policy was pushed by Shumlin in the early part of his first term to shut off every conceivable support for VTY while the courts chastised Vermont for denying they used safety to attempt to shut this company down. We now are seeing a foreign company take this step and we also have 70% of our power coming from another foreign company………..who cares! Something is very wrong with this picture !!!!

  • Pete Novick

    The heat in an operating reactor is produced by the fission of fissile isotopes.

    When the reactor is shut down automatically in an emergency (SCRAM), all control rods are inserted and the reactor is shutdown, the fission reactions essentially stop and the power drops drastically to about 7% of full power in 1 second.

    Power does not drop to zero because of the radioactive isotopes that remain from the prior fissioning of the fuel. The decay radiation then deposits most of its energy in the fuel.

    Decay heat must be removed at the same rate it is produced or the reactor core will begin to heat up. The removal of this heat is the function of the various reactor core cooling systems that provide water flow through the reactor core and then reject the heat elsewhere.

    At Fukushima, emergency systems were compromised by the large tsunami that resulted from the earthquake, and made it difficult for the operators to keep up with removing the decay heat.

    If Entergy wants to build a D/G set to add redundancy, improve the capacity to remove decay heat after a SCRAM and thereby lower risk to people living in the EPZ, I think that’s a good idea.

    • Pete,

      The layout of the Fukushima plants was incorrect.

      The auxiliary systems, such as D/G sets, auxiliary transformers, etc., should not have been on the ocean side, but on the inland side AND on a tsumami-proof elevated land area. A major plant layout error made decades ago.

      The plants would not have looked so pretty from the inland side.