Power Plant of the Week - Pilgrim Nuclear Generating Station

As we prepare to celebrate Thanksgiving, its a great time to think about the Pilgrim Nuclear Generating Station (Pilgrim) in Plymouth, MA. Its just a little ways southeast of Plymouth Rock in Plymouth Harbor, where the Pilgrims first set foot on the Massachusetts mainland. Pilgrim is owned by Entergy Corp (NYSE: ETR) which has owned and operated the plant since the late 1990s. It consists of one boiling water reactor with a nameplate capacity of approximately 680 MW. The story of Pilgrim is a familiar one in New England. The plant was constructed by the Boston Edison Company (NStar predecessor) and entered service in 1972. During deregulation, it was divested by NStar and acquired by Entergy.

Pilgrim as viewed from the south

Pilgrim as viewed from the south

During the late 1990s, Entergy acquired several nuclear plants throughout the northeast in states that were part of electric industry restructuring. Entergy's acquisitions were part of a trend during deregulation where merchant generators with deep expertise in nuclear operations took over nuclear plants that were formerly run by regulated utilities. The result, for most plants, was a significant increase in uptime, safety, and profitability under these new owners who specialized in nuclear plant operations. It was also important for the industry to have firms with significant financial resources running these plants due to their complexity, age, and the potential for costly repairs that could overwhelm a smaller utility owner. 

Nuclear plants are well suited to providing baseload power as they are either on or off with limited ability to run at partial capacity. The graphs below show the capacity factor of the Pilgrim plant over the last several years and a close up view of performance over the last 12 months. You'll note that Pilgrim has been a reliable resource to the ISO-NE grid with very high availability since the mid-2000s. The periodic dips in capacity factor are generally associated with refueling outages. The spring of 2013 was a bit of an outlier as equipment issues forced the plant offline for several weeks. 

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Pilgrim has been in the news a lot over the last two years since it has been in the process of renewing its license to operate which is granted by the Nuclear Regulatory Commission. The majority of the U.S. nuclear fleet is undergoing re-licensing since most plants were built between the late 1960s and mid 1980s. As these plants reach the end of their initial operating licenses, they must undergo a rigorous process for relicensure in order to stay operational. Invariably, the relicensing process provides an opportunity for supporters and opponents of nuclear power to engage in a heated public debate. Pilgrim, like most nuclear plants, has some very vocal opponents including Pilgrim Watch and the Cape Downwinders

Pilgrim's safety record has been good and the NRC is a strong regulator, but despite this, there will always be people who fear nuclear power. Accidents at poorly run facilities such as Fukushima don't help the image of the industry and geographical bottlenecks can cause anxiety among people who fear a nuclear incident. Some concerns of nuclear opponents are legitimate and one such concern is nuclear waste from spent fuel rods. The politics and paralysis around the Yucca Mountain long term storage facility has forced nuclear plants throughout the US to devise on-site storage solutions. Pilgrim is no different and is currently in the process of moving spent fuel rods into dry cask storage on-site. The embedded slideshow below provides additional information on dry cask storage at Pilgrim.

Another valid issue raised by nuclear plant opponents is thermal pollution and the damage to aquatic species caused by once-through cooling. Many older fossil plants also use once through cooling. The environmental impact statement required under NEPA as part of the Pilgrim re-licensing process illustrates the impacts of the cooling system to aquatic species. Specifically, aquatic species get trapped on the intake to the plant and are unable to escape due to the flow velocity. Also, some species are impacted by abnormal thermal gradients near the outflow as waste heat is discharged. During the summer of 2013, nature retaliated as the waters in Cape Cod Bay became unusually high and Pilgrim was forced to reduce output since the intake cooling water temperature exceeded specifications. The graphic below illustrates the intake and discharge locations for cooling water at the plant. Note that the intake is located within the protected embayment while the discharge sends water directly out into Massachusetts Bay.

Fig. 2-3 from Pilgrim EIS

Fig. 2-3 from Pilgrim EIS

Nuclear power plants tend to have very high staffing levels compared with fossil fuel plants. As a result, the impact on local employment is significant. Pilgrim employs over 600 people and there are many related jobs among subcontractors and other service personnel. Workers at Pilgrim are represented by the Utility Workers Union of America, Local 369. The presence of a highly professional union provides another check and balance against attempts to cut corners in the operation of a nuclear plant. Pilgrim is also a substantial contributor to the tax base of Plymouth, MA and currently contributes approximately $10M annually to the town government through a payment in lieu of taxes.

Although some of the issues raised by Pilgrim opponents are valid, Energy Tariff Experts poses the following questions:

Q: What would happen to ISO-NE  power prices if Pilgrim closed? 
A: They'd go up a lot.

Q: How can we transition to a reliable, reasonably priced, low carbon electric grid in America w/o nuclear as part of the mix?
A: We can't, if you want low carbon you need nuclear for baseload.

Q: Why can't we build new nuclear in America?
A: Absent financing issues in the merchant generation space, we don't know because the new reactor designs are much safer than the current operating fleet and for those concerned about safety, new nuclear builds would be a good thing.

In summary, as we celebrate Thanksgiving in 2013, we should celebrate the reliable performance of Pilgrim and its contribution to the ISO-NE electric grid and the regional economy.