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Ivanpah Hitting First ‘Forbearance’ Milestone With Performance on the Rise

UPDATE (August 9, 2016) — In a filing today, NRG Energy confirms that Units 1 and 3 met their production requirements under the forbearance agreements, extending those agreements through January 2017. From the filing: “Subsequent to the close of the second quarter of 2016, each of Ivanpah’s unit 1 and unit 3 satisfied their respective production requirements for the initial six-month measurement period under the forbearance agreements.” H/T to NRG’s David Knox for the notification.

Original post:

Energy production was up at Units 1 and 3 at Ivanpah in the first half of 2016, despite a highly publicized fire in May, suggesting the solar power plant is likely to get additional time as it works to make good on its contracts with Pacific Gas & Electric.

Ivanpah failed to meet guaranteed production minimums for the PG&E-contracted units in the plant’s first two years of operation, 2014 and 2015, and faced default. But PG&E and California regulators granted the plant, led by majority owner and operator NRG Energy, a reprieve – “forbearance agreements” that put the original power purchase agreements, with their escalating production requirements, on hold while Ivanpah tries to step up its game.

The forbearance agreements run for an initial period of six months – February 1 through today – and call for a six-month extension “if the Projects meet certain production requirements during the initial six-month period,” according to California regulators (PDF).

Those “certain production requirements” are confidential, but reports to federal energy agencies* indicate the two units that sell power to PG&E have performed well, with generation from February 1 through June 30 of 221,271 megawatt hours, a 16 percent increase compared to the same period in 2015. It’s an increase of 87 percent over 2014, as well.


Assuming July proceeded without incident and that the six-month thresholds weren’t onerous, that would seem to set the plant up for another six months of forbearance. That would then give Ivanpah the opportunity to face the next year of its PG&E contracts, which measure performance on a two-year rolling basis, without the burden of its dismal first year.

“While the fire obviously impacted our operations, we are pleased with our generation on all units since coming back online,” NRG spokesman David Knox said in an email. “We will be reporting the six month forbearance results to PG&E in August.”

NRG has described a number of engineering fixes that have helped improve performance – see this piece by Susan Kraemer for details. It’s also true that Ivanpah is using significantly more natural gas this year than in its first two years of operation.

The plant uses “night preservation” boilers to keep seals intact overnight and “auxiliary” boilers to get it jumpstarted in the morning. The auxiliary boilers are also used in “supplementing solar generation during periods of transient clouds or at the end of the day,” according to technology provider BrightSource.

From January through May, the two PG&E-contracted units together used 381.2 mmcf of natural gas – 188.5 mmcf for Unit 1 and 192.7 mmcf for Unit 3. That’s an increase of 42 percent over the same period in 2015.


Still, each unit is allowed to use 525 mmcf annually (up from the original cap of 384 mmcf), so it doesn’t look like staying under the limits will be a big problem.

*Reports to the Federal Energy Regulatory Commission provided quarterly data for January through June. Reports to the Energy Information Administration provided monthly data for January through May. The reports are generally 99.5 percent consistent with each other, and were blended to determine output for the February 1-June 30 period.

Ivanpah the Bug Killer

If you’ve heard of Ivanpah, you’ve heard of “streamers” – birds set aflame in flight, raining fire from the sky with regularity, at the Ivanpah Solar Electric Generating Station in California..

Well, a newly published peer-reviewed study indirectly suggests the plant might have gotten a bum rap with all that talk.

The widely accepted view of Ivanpah as a massive bird incinerator has its origins at the National Fish and Wildlife Forensics Laboratory. Staff from the lab, as well as U.S. Fish and Wildlife Office of Law Enforcement personnel, visited Ivanpah for a few days in October 2013 and wrote of seeing “streams of smoke rise when an object crosses the solar flux fields aimed at the tower.”

Fried birds, they presumed.

When told by Ivanpah employees that many of the streamers weren’t birds but were instead insects or debris, the feds weren’t completely dismissive, but they sounded skeptical. After all, they wrote, “there were instances in which the amount of smoke produced by the ignition could only be explained by a larger flammable biomass such as a bird.” Plus, they has “observed birds entering the solar flux and igniting, consequently becoming a streamer.”

Eventually, their observation of seeing “a streamer event every minute or two,” became the incendiary lead to an Associated Press story about Ivanpah and birds.

But it turns out more streamers than they thought might not be birds.

In May and September of 2014, a team from the U.S. Geological Survey conducted research at Ivanpah into ways of “detecting animals flying around solar power towers.” To do so, among other things they set up sophisticated video cameras and radar equipment and conducted hundreds of hours of surveillance.

Their equipment captured a lot things flying around the towers, and after looking at all the images and videos they made some observations:

  1. “Puffs of smoke and other flashing objects moving in and through the flux around solar towers can be visually confusing.”
  2. “In general, the smoke created by a burning object can make it appear larger and more dynamic, and this was particularly true in the solar flux around solar towers.”
  3. “Billowing, brightly illuminated smoke moving through the flux around solar towers sometimes created the illusion of birds in flight.”
  4. “Further complicating matters, occasionally birds could be seen flying high above the tower and were visible only as small white objects in the background, while similarly small-looking objects (presumably insects) simultaneously burned and smoked in the visual foreground.”
  5. “Sometimes the visual trails of these distant birds and those of closer, smoking objects intersected and created the illusion of the birds disappearing in smoke. However, we never observed evidence indicating that birds were completely incinerated by the solar flux.”
  6. “Our collective observations indicate that most of the small objects observed smoking in the flux were insects.”

Now, this doesn’t prove that Ivanpah isn’t a threat to birds (and it says nothing about the plant’s impact on desert tortoises, or the worthiness of its technology). Birds are killed at the plant, although not in nearly the numbers some had projected. But it is a reminder of the power of provocative language and images to overwhelm a complex risk-benefit question.

Ivanpah Bird Deaths Revised Up, but Risk Remains ‘Low’

The Ivanpah solar project is deadlier to birds than previously thought, but the plant still presents a low risk to any species or group of species, according to a new report.

In April 2015, the annual monitoring report prepared for the California Energy Commission estimated 3,504 birds died at the solar power tower plant in the Mojave Desert in its initial year of operation, ending in October 2014. The Year 2 report (PDF), filed late last month, revises that first-year number up to 5,128, while estimating that 5,181 birds died at the plant in the most recent operating year.

The report’s preparer, Western EcoSystems Technology, said the revision to the first-year number reflects improved understanding of bird migration timing and better information about how many of the birds that die at the plant are being found by searchers.

After coming up with a Year 2 estimate using the same methodology as in Year 1 – 6,186 – the company went through and applied the improved methodology to both years and arrived at the revised numbers.

“Overall, the estimates calculated using biologically informed seasons are greater for the first year, lower for the second year, and greater overall for both years combined. The changes are driven by two main factors: re-categorizing a number of detections from winter seasons to fall seasons because a monitoring year ends in fall, and the effect of additional bias trial data from the period between 21 October 2015 and 15 December 2015,” the report said.

In the end, “the new analysis does not change any conclusion of the impacts of the Project” on birds, the report said, categorizing that risk as “low.”