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.
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.
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:
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.
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.”
UPDATE: About 10 days after original publication, NRG got back to me with corrected and previously missing data, necessitating minor changes throughout this piece. The upshot: Gas usage was up 62 percent, not 59 percent, in Year 2, and emissions were 229 pounds CO2-equivalent per MWh in Year 2, not 225.
Natural gas consumption at Ivanpah, the controversial power plant in the California desert, increased 62 percent in its second full year of operation, and the plant emitted the equivalent of about 229 pounds of carbon dioxide for each megawatt hour of electricity it generated.
How’s that compare?
It’s about one-fifth the emissions of the average U.S. power plant and a bit over one-quarter the emissions of a recently built combined cycle natural gas-fired power plant in California.
But of course Ivanpah is considered a renewable energy source by the state, like utility-scale solar PV, which according to the National Renewable Energy Laboratory puts out 18 to 22 pounds of CO2 per megawatt hour of energy produced. In other words, CO2 emissions at Ivanpah are at least 10 times those of solar PV.*
Ivanpah used 1,251 million cubic feet (mmcf) of gas in the 12 months ended January 31, a figure based on preliminary data obtained from the U.S. Energy Information Administration.
The $2.2 billion Ivanpah Solar Electric Generating System, with tens of thousands of reflecting mirrors and giant “power towers” that heat water to generate thermal power, was fully online by February 1, 2014. It generated 430,488 MWh of electricity in its first 12 months of operation, according to the EIA, while consuming 773 mmcf of natural gas. That slow start left the plant in danger of defaulting on its PPAs with the utility PG&E (see: “Ivanpah Not Out of the Woods Yet“). In Year 2, the plant produced 655,926 MWh of electricity, a 52 percent increase.
Under its original licensing, Ivanpah’s three units were permitted to burn a total of 984 mmcf of natural gas annually. But a few months after the plant began commercial operations, Solar Partners – consisting of majority owner NRG, along with Google and technology developer BrightSource Energy – asked and then received approval from the California Energy Commission to use as much as 1,575 mmcf in a year.
So in Year 2, Ivanpah ended up using about 25 percent more gas than originally planned, but about 22 percent less than the revised limit.
The overall limit isn’t the plant’s only consideration when it comes to natural gas, however, not with PG&E and Southern California Edison counting Ivanpah electrical output toward their obligations under California’s renewable portfolio standard. To qualify as a renewable energy source, state law limits the amount of “non-renewable energy that may be included with renewable energy at no more than two percent of total fuel use.” But the law allows wiggle room up to 5 percent in special circumstances, an allowance granted to Ivanpah.
Is Ivanpah using less than 5 percent natural gas?
Depends on how you look at it.
Ivanpah relies on gas in “night preservation” and “auxiliary” boilers. As BrightSource has explained, “night preservation boilers are very small boilers used overnight to maintain seals and preserve heat.” As for the auxiliary boilers, again quoting BrightSource, they are used for:
BrightSource says “this type of natural gas does not produce electricity. In fact, it increases the amount of electricity produced through the sun.”
The gas used at Ivanpah in Year 2 would have produced 180,000 MWh at a modern natural gas-fired power plant like the Lodi Energy Center, opened in late 2012. Although that’s equivalent to 27 percent of Ivanpah’s total Year 2 electricity generation, regulators say Ivanpah has not been using more than 5 percent non-renewable fuel.
That’s because the regulators don’t count most of the fuel used for the purposes listed by BrightSource. If the gas wasn’t burned between the start of generation and the end of generation each day, it’s like it didn’t happen.
This allows NRG to say that less than 5 percent of the electricity generated at Ivanpah resulted from burning natural gas. (Under this calculation, in Year 2, 4.3 percent of electricity generated at Unit 1 came from burning gas; 4.1 percent at Unit 2; and 4 percent at Unit 3. Overall, the figure was 4.1 percent.)
But of course, the gas used for all the other purposes at Ivanpah was still burned, and presumably because it had to be in order for the plant to function. And the emissions were still emitted.
As Dan Danelski revealed last year in the Riverside Press-Enterprise, Ivanpah’s emissions are hefty enough to qualify it as a polluter under California’s cap-and-trade program.** Based on its natural gas consumption, emissions in Year 2 of the plant’s operation were about 68,097 metric tons. That’s 150,128,000 pounds – thus the 229 pounds per megawatt hour figure.
The Lodi gas-fired power plant pumps out about 837 lb/MWh.
It’ll be interesting to see what happens to Ivanpah’s gas consumption in Year 3. The most notable trend evident in Year 2 was a big increase in use at the end of the year – in the three month period from November 2015 through this January, consumption was up 142 percent.
*NREL estimates full life-cycle emissions for solar PV at 88 lb/MWh, with 21 to 26 percent attributed to operational processes, including power generation and system operations and maintenance. See this PDF.
**Danelski reported on 2014 calendar year emissions. But the three Ivanpah units began delivering electricity at various points in January that year, and NRG and PG&E are using February 1, 2014, as a starting point in measuring performance of the two units under contract to PG&E. This analysis follows suit for the entire plant.
In “forbearance agreements” recently approved by California regulators, Pacific Gas & Electric has given the owners of the Ivanpah solar power tower plant up to an extra year to reach energy production levels called for in contracts for two of the plant’s three units. Based on how those units have done so far and what will be required down the road, achieving those minimums won’t be easy.
New data from the U.S. Energy Information Administration indicate that for the first 24-month measuring period called for under the PG&E power purchase agreements, Unit 1 fell 61,692 megawatt hours shy of the 425,600 MWh production guarantee apparently set out in the PPAs. The slightly more powerful Unit 3’s production gap was even greater, 103,544 MWh, toward a goal of 469,840 MWh.
That said, in their second full year of operation, which officially ended at the close of January this year, both units performed much better than in their first year, with Unit 1 production up 29 percent and Unit 3 up 34 percent.
Here’s the issue, though: Under the PPAs, the bar rises. This snippet, from a BrightSource Energy filing several years ago, is what we know about the confidential PPAs (Solar Partners II is Unit 1 and Solar Partners VIII is Unit 3):
So instead of hitting 140 percent of “contract quantity” in a 24-month period (or 70 percent per year on average), Solar Partners now apparently needs to ratchet production up to 160 percent (or 80 percent per year on average). California Public Utility Commission documents related to the recently approved forbearance agreements note that this is a rolling 24-month measurement period, so every month from now on, for the life of the 25-year contracts, the units must hit 160 percent of the annual contract quantity for the preceding 24 months.
Those forbearance agreements push that requirement out six months, at least, and more likely for a year — so it’ll be starting next February, then going forward, when this new target will have to be met.
It will require major increases in production.
Take Unit 1. Its 24-month target — that is, the minimum it needs to produce to avoid being in default — come February 2017 will be 486,400 MWh. With 213,126 MWh in the 12 months ended January 31 this year, that means the unit will need to generate 273,274 MWh over the following 12 months – an increase of 28 percent. That’s as big an increase as it had this past year, but off a larger base.
The challenge for Unit 3 is even steeper. It will need to increase production from 220,595 MWh to 316,365 MWh to reach a target of 536,960 MWh. That’s a 43 percent increase, a significant step up from the 34 percent increase the unit managed from Year 1 to Year 2, and again it’s coming off a larger base.
UPDATE: Footnotes have been added to elaborate on a few of these items, most notably the comparative price of energy between Ivanpah and Crescent Dunes.
It uses mirrors and a giant tower, like the Ivanpah Solar Electric Generating System in California, and molten salt like Solana Generating Station in Arizona. But SolarReserve’s Crescent Dunes, now in “full commercial operation” [PDF], is different from any large-scale power plant that came before it in several important ways.
1. Unlike Ivanpah, Crescent Dunes, in Nevada, was built with the ability to store energy and dispatch power when needed.
At Crescent Dunes, giant mirrors focus the sun’s energy at the top of a tower, heating a mixture of sodium and potassium nitrate. This molten salt can be used immediately to superheat water and produce electricity in the manner of any other thermal power plant. Or it can be stored in insulated tanks to drive the thermal-power process during periods of cloudy weather or at night.
At Ivanpah, the “heliostats” focus the sun’s energy atop towers to heat water, which won’t hold the heat for long. That means the vast bulk of Ivanpah’s production comes at the same time the California grid is being fed large and rapidly increasing amounts of power from solar PV plants. Ivanpah can provide a smoother flow of electricity than a PV plant, but its value is still limited by immediate reliance on the sun.
2. Solana can store energy, too, but Crescent Dunes claims an advantage over the Arizona plant.
As SolarReserve CEO Kevin Smith told me last year: “We’re using molten salt directly,” giving Crescent Dunes the ability to drive the temperature of the heat-holding salts 300 degrees higher than at Solana, where long rows of parabolic mirrors are used to first heat a transfer fluid. “They need two or three times the salt we have to get the same amount of heat storage,” Smith said. That leads to a bigger, more expensive footprint – “a whole lot more tanks, pumps and salt.” In sum, Smith said, the multistep nature of the Solana process results in less efficient operation.
3. Unlike Ivanpah, Crescent Dunes doesn’t burn fossil fuels.
In 2014, Ivanpah used 867 million cubic feet (mmcf) of natural gas. It helps jump start the system in the morning, mostly, and to get through some cloudy periods. At a typical gas-fired power plant, that would produce around 85 gigawatt-hours of electricity. Ivanpah produced 420 GWh in 2014 – so you could say natural gas use was equal to about 20 percent of the plant’s output. This is way over the 5 percent allowed by California regulations, but a California Energy Commission spokesman said much of the natural gas Ivanpah uses isn’t held against it.
“(N)atural gas used between the end of daily generation and the start of generation the next day is not considered as contributing to electricity generation and therefore, not included in calculating the percent of non-renewable fuel used at the facility,” the CEC’s Michael Ward said in an email earlier this month.
Ivanpah’s output jumped up to 652 GWh in 2015, so if natural gas use held steady, the plant’s generation-to-gas-use ratio would have improved substantially. But while we won’t know exactly how much gas Ivanpah used in 2015 for a few months, some hints are available: Between August and November in 2015, gas consumption at one of its three units was double what it was in 2014.
4. Crescent Dunes should break out of the gate faster than Ivanpah.
Ivanpah went into full commercial operation in February 2014, not even three and a half years after construction began. Despite being one-third the size of Ivanpah, Crescent Dunes took at least four years to achieve that status.NOTE A One reason Crescent Dunes was slower to start up: SolarReserve saw what happened when Ivanpah’s early production fell dramatically short of ultimate expectations.
“We certainly recognized that Ivanpah got hammered,” Smith told me. “From a management perspective, that led us to want to be more cautious.” That was a year ago, when Crescent Dunes seemed on the precipice of startup, but it wasn’t until today that SolarReserve heralded the plant’s opening.
After the fact, Ivanpah’s operators said they expected all along that it would take up to five years to hit long-term performance targets. But they didn’t make that clear at the plant’s grand opening.NOTE B And, as my reporting has revealed, performance has even fallen short of contractual obligations that anticipated a slow start.
After taking extra time to dial in performance, SolarReserve was confident enough to say today that “Consistent with the rollout plan, the facility will ramp up to its full annual output over the coming year.” The target number: 500 GWh/year beginning in Year 2. Yes, we will be watching.
5. Crescent Dunes electricity is less expensive than Ivanpah electricity.
Crescent Dunes is selling its output to NV Energy for 13.5 cents per kilowatt-hour, rising 1 percent a year during the life of the 25-year power purchase agreement. Ivanpah’s contracts with PG&E and Southern California Edison are confidential, but filings with the Federal Energy Regulatory Commission show that during the high-demand July-September period last year, the utilities paid between 20 and 22 cents per kWh for Ivanpah electricity.NOTE C During the same period, Solana sold electricity to Arizona Public Service at 12.8 cents/kWh.
NOTE: This post has been updated and expanded for KQED News.
Ivanpah, the biggest power-tower solar plant in the world, is doing better after woeful energy production in its first year of operation in 2014. But not better enough.
In its quarterly report filed in November, majority owner NRG Energy says it faces a default on its contracts with Pacific Gas & Electric, which has power purchase agreements for production from two of the plant’s three units:
Ivanpah Energy Production Guarantee — The Company’s PPAs with PG&E with respect to the Ivanpah project contain provisions for contract quantity and guaranteed energy production, which require that Ivanpah units 1 and 3 deliver to PG&E no less than the guaranteed energy production amount specified in the PPAs in any period of twenty-four consecutive months, or performance measurement period, during the term of the PPAs. If either of Ivanpah units 1 and 3 deliver less than the guaranteed energy production amount in any performance measurement period, PG&E may, at its option, declare an event of default. Based on the energy production amount since January 2014, the Company expects that the units will not meet their guaranteed energy production amount for the initial performance measurement period. The Company is exploring options to mitigate this risk or its consequences.
Electricity production at Ivanpah was up 71 percent in the first nine months of 2015 compared to the same period in 2014. But 2014 was so dismal, the plant still won’t be able to meet the production guarantee outlined in SEC filings:
The “contract quantity” for each year is expected to be 304,000 MWH for Solar Partners II (Unit 1) and 335,600 MWH for Solar Partners VIII (Unit 3) throughout the delivery term, and the seller must deliver a guaranteed amount of energy in two-year measuring periods. The production guarantee generally is 140% of the contract quantity during the first measuring period after the commercial operation date and 160% in subsequent measuring periods, subject to reduction if the project company is unable to deliver power due to a force majeure or curtailment.
Unit 1 declared commercial operations on January 10, 2014, and Unit 3 on January 15, 2014. Through September 2015, Unit 1 had produced 319,994 megawatt-hours, according to the Energy Information Administration. Its production guarantee during the first measuring period works out to 425,600 MWh. Based on past performance and trend, the unit will probably fall at least 50,000 MWh short of that threshold. Unit 3 was at 311,057 MWh through September toward a goal of 469,840, so its shortfall will likely be even greater.
You have to wonder how PG&E might proceed here. Would it be interested in getting out of its Ivanpah contracts, if it could? The utility needs renewable energy, like that produced at Ivanpah, to meet California’s aggressive renewable portfolio standard. That said, the Ivanpah contracts date back several years (last amended in 2010, it appears), and renewable energy prices have plunged recently. Consider: In the third quarter of this year, PG&E paid $201.99/MWh for electricity from Ivanpah’s Unit 3. Meanwhile, PPAs for utility-scale PV in the Southwest in the past year have fallen to around—and in some cases below—$50/MWh.
Update: What about Unit 2, you ask? Electricity from Ivanpah Unit 2 (Solar Partners I) is sold under a power purchase agreement to Southern California Edison. The production standard for Unit 2 is essentially the same as for Units 1 and 3 and it, too, will fall well short two years after going into operation on January 31, 2014. So why did it escape mention in NRG’s filing? The apparent answer: The PPA with Edison doesn’t leave NRG (and minority owners BrightSource and Google) similarly vulnerable to a default declaration. According to a BrightSource filing, the contract stipulates only that “If these production levels are not met, the project company will have to pay SCE for replacement power.” (12/9/2015)