Nuclear outages jumped 50% this summer

[kristopher]

EIA: Nuclear outages jumped 50% this summer
By Robert Walton | September 7, 2016

Dive Brief:
- Nuclear outages spiked between June and August, according to new data from the U.S. Energy Information Administration, averaging 4.3 GW, or about 51% more than in 2015.

- It is an unclear comparison, however, as EIA pointed out that nuclear outages last year reached their lowest level since 2007. In August of 2015, for instance, outages totaled just 0.1 GW during four days.

- This year, summer outages were at their highest in June, reaching 9.9 GW—roughly 10% of total U.S. nuclear capacity on the 17th of that month. Nuclear facility outages averaged 6.2 GW for the month, compared with 4.4 GW of outages in July and 2.4 GW in August.

<snip>

Total U.S. nuclear capacity is now 98,672.0 MW, according to EIA's nuclear outage tracker. As of Sept. 2, the country has almost 4,200 MW offline for a total of about 4.25%....

Expanded coverage: http://www.utilitydive.com/news/eia-nuclear-outages-jumped-50-this-summer/425845/

Large scale generation that drops out of the grid with no notice requires spinning reserves - that is, operating fossil generators 24/7 as 'instant on' replacement. Note well that all of the 98+GW mentioned above requires enough fossil fuel spinning reserve to ensure there is no disruption should any given nuclear plant experience one of their not rare, often extended, emergency shutdowns.
The case below wasn't disruptive, but there is a pretty significant carbon cost associated with ensuring that lack of disruption.

Plymouth Nuclear Power Plant Shut Down for Second Time in Three Weeks
Federal regulators downgraded the Bay State’s last reactor in 2015.

By Kyle Scott Clauss | Boston Daily | September 7, 2016, 10:10 a.m.

Pilgrim Nuclear Power Station in Plymouth shut down as a result of a mechanical issue Tuesday morning, marking the second time in roughly three weeks that the 44-year-old facility was powered off.

...the power plant experienced an “unplanned shutdown” around 8:35 a.m., after water levels unexpectedly spiked in the reactor. Pilgrim also shut down in mid-August to repair a failure of a main steam isolation valve.

...

Massachusetts’ last remaining nuclear power plant, Pilgrim is scheduled to close in 2019, citing “poor market conditions, reduced revenues and increased operational costs.” ...

http://www.bostonmagazine.com/news/blog/2016/09/07/plymouth-nuclear-power-plant/

[ChairmanAgnostic]

1. I get it that night skies and clouds can disrupt solar,

but how does one disrupt wind power? Between the rotation of earth, solar radiation, thermal layers, and varying amounts of HOH in the air, we will ALWAYS have wind.

Nukes are surprisingly reliable, but the long term costs and dangers are significant.

[kristopher]

2. reliable power is met by generating plants collectively, not individually

The “baseload” myth
Brand rejects the most important and successful renewable sources of electricity for one key reason stated on p. 80 and p. 101. On p. 80, he quotes novelist and author Gwyneth Cravens’s definition of “baseload” power as “the minimum amount of proven, consistent, around-the-clock, rain-or-shine power that utilities must supply to meet the demands of their millions of customers.” (Thus it describes a pattern of aggregated customer demand.) Two sentences later, he asserts: “So far [baseload power] comes from only three sources: fossil fuels, hydro, and nuclear.” Two paragraphs later, he explains this dramatic leap from a description of demand to a restriction of supply: “Wind and solar, desirable as they are, aren’t part of baseload because they are intermittent—productive only when the wind blows or the sun shines. If some sort of massive energy storage is devised, then they can participate in baseload; without it, they remain supplemental, usually to gas-fired plants.”

That widely heard claim is fallacious. The manifest need for some amount of steady, reliable power is met by generating plants collectively, not individually. That is, reliability is a statistic- al attribute of all the plants on the grid combined.If steady 24/7 operation or operation at any desired moment were instead a required capability of each individual power plant, then the grid couldn’t meet modern needs, because no kind of power plant is perfectly reliable. For example, in the U.S. during 2003–07, coal capacity was shut down an average of 12.3% of the time (4.2% without warning); nuclear, 10.6% (2.5%); gas-fired, 11.8% (2.8%).25 Worldwide through 2008, nuclear units were unexpectedly unable to produce 6.4% of their energy output.26 This inherent intermittency of nuclear and fossil-fueled power plants requires many different plants to back each other up through the grid. This has been utility operators’ strategy for reliable supply throughout the industry’s history. Every utility operator knows that power plants provide energy to the grid, which serves load. The simplistic mental model of one plant serving one load is valid only on a very small desert island. The standard remedy for failed plants is other interconnected plants that are working—not “some sort of massive energy storage [not yet] devised.”

Modern solar and wind power are more technically reliable than coal and nuclear plants; their technical failure rates are typically around 1–2%. However, they are also variable resources because their output depends on local weather, forecastable days in advance with fair accuracy and an hour ahead with impressive precision. But their inherent variability can be managed by proper resource choice, siting, and operation. Weather affects different renewable resources differently; for example, storms are good for small hydro and often for windpower, while flat calm weather is bad for them but good for solar power. Weather is also different in different places: across a few hundred miles, windpower is scarcely correlated, so weather risks can be diversified. A Stanford study found that properly interconnecting at least ten windfarms can enable an average of one-third of their output to provide firm baseload power. Similarly, within each of the three power pools from Texas to the Canadian border, combining uncorrelated windfarm sites can reduce required wind capacity by more than half for the same firm output, thereby yielding fewer needed turbines, far fewer zero-output hours, and easier integration.

A broader assessment of reliability tends not to favor nuclear power.Of all 132 U.S. nuclear plants built—just over half of the 253 originally ordered—21% were permanently and prematurely closed due to reliability or cost problems. Another 27% have completely failed for a year or more at least once. The surviving U.S. nuclear plants have lately averaged ~90% of their full-load full-time potential—a major improvement for which the industry deserves much credit—but they are still not fully dependable. Even reliably-running nuclear plants must shut down, on average, for ~39 days every ~17 months for refueling and maintenance. Unexpected failures occur too, shutting down upwards of a billion watts in milliseconds, often for weeks to months. Solar cells and windpower don’t fail so ungracefully.

Power plants can fail for reasons other than mechanical breakdown, and those reasons can affect many plants at once. As France and Japan have learned to their cost, heavily nuclear-dependent regions are particularly at risk...

http://www.rmi.org/Knowledge-Center/Library/2009-09_FourNuclearMyths

[ChairmanAgnostic]

3. Fascinating.

And not in the Star Trek sense.


Thanks.

[kristopher]

4. Not sure what that usage involves, but in any case...

you're welcome.