Is California hedging its bets on an old solar warhorse, or is it protecting a crucial part of California’s renewable framework? That’s the reasoning process following the California Public Utilities Commission’s decision to prevent PG&E from exercising their option to abandon their contract with the Ivanpah Solar Electric Generating Facility. This means that Ivanpah operates two of three plants despite being inefficient and environmentally problematic, among other issues, according to its critics.
Ivanpah is located in the Mojave Desert near the Nevada border and is a CSP facility that uses 173,500 computerized mirrors to focus the sun’s rays on boilers housed at the top of 459-foot-tall towers. The concentrated sun’s rays boil water at almost 1,000 degrees Fahrenheit to spin turbines. The massive facility, erected at an investment of $2.2 billion in 2014, was touted as the world’s largest CSP plant when it went operational and had an output of 386 megawatts. It was developed by NRG Energy, Google, and Kelvin Energy and received a $1.6 billion loan guarantee from the DOE.
The 30-year contracts that PG&E signed with CSP developers in 2009 were supposed to last until 2039. However, because CSP with higher efficiency factors and the ability to produce electricity at about half the cost per kilowatt hour currently offered by PV solar has made Ivanpah CSP uneconomic by way of comparison, the Ivanpah CSP was put out of commission. PV solar systems generate electricity from sunlight directly. Currently, PV costs about $0.03 per kWh. CSP currently costs about $0.06 per kWh. PV can also be combined with energy storage.
However, PG&E’s termination request was rejected by CPUC in spite of support from DOE and an independent evaluator. This is because CPUC cited Ivanpah’s importance in enabling reliability, California’s target in 2045 for 100% renewable power, and possible stranded investments in reliability assumptions. This implies that removal of Ivanpah before development and construction takes place might leave reliability in jeopardy in order to meet peaking or weather-related reliability requirements.
Right from inception, Ivanpah struggled with issues of operating capacity. Cloud cover, as well as sporadic sunlight, necessitated a massive dependence on natural gas in a bid to maintain production at optimal levels; thus, permission was granted by regulatory bodies to boost annual gas consumption from 328 to 525 million cubic feet in 2014. According to American Energy Institute Director, Jason Isaac, this particular project “never lived up to expectations,” to stay in operation through gas support.
The other controversy involving the environmental aspect of the Ivanpah solar facility involves birds dying due to collisions with the concentrated sunbeams emitted by the facility to produce heat. Studies have recorded thousands of bird deaths annually due to the concentrated sunbeams. Additionally, some studies recorded a bird catching fire in mid-air every two minutes in the early stage studies involving the solar units.
In 2016, an analysis indicated that the U.S.-based solar power plants are estimated to cause an average of 9.3 to 10.7 bird deaths per megawatt per year, compared to an estimated rate of bird death per megawatt in fossil-fuel
On the technical side, Ivanpah is a stepping-stone, a proof of concept for CSP that worked technically, albeit eclipsed by the economic viability of PV. CSP has huge potential, particularly through integrated thermal energy storage, to make dispatchable solar power, although Ivanpah’s lack of MWe-scale energy storage allows little focus on serving peak evening demands. Its continued use drives the narrowing gap between maintaining a diversified, robust power structure versus a plan to retire higher-priced, even less efficient facilities.
PG&E says the benefit of terminating the contracts is cost savings with no threat of noncompliance with renewable standards. The reason for the CPUC’s ruling has even broader implications: maintain the operation of legacy facilities until the replacement capacity is identified. As Ivanpah enters its second decade, the future of Ivanpah reflects the shifting nature of solar economics. Ivanpah was once innovative for its concentration solar, but it currently finds itself dwarfed by the PV revolution. Nonetheless, it seems that for now, Ivanpah’s three towers continue to shine in the California desert as testaments to what the state once wanted for its clean energy future.
