Is Ivanpah online?

The world's largest solar thermal plant opened this week to much fanfare. But its actual contribution to the grid thus far has been hard to measure.


A number of media reports have stated that the massive Ivanpah solar thermal electric plant in California’s desert has recently come online. The truth is more complex.

On February 5, California hit another record for peak generation of large-scale solar, reaching 2.378 GW at noon. This is 230 MW more than the last record in early January, and led me to speculate that we were finally seeing output from the 377 MW of net capacity at the massive Ivanpah solar thermal electric plant.

In previous days, publications including Think Progress had put out big headlines stating that Ivanpah, the world’s largest solar plant, had finally come online. But digging a little deeper into data from the California Independent System Operator shows that this is an overstatement at best, and misses the complex commissioning process that the plant has undergone. It turns out that the big jump in power on February 5 was mostly solar photovoltaic panels and, as I write this, Ivanpah’s three units are still not producing full power for the grid.

That is not to say that the plant is producing no power. Ivanpah began its first test production of power from unit 1 last September, and has since synched the other two units to the grid.

Digging deeper

How much power at this time? It is likely that only owner NRG, technology supplier Brightsource, construction contractor Bechtel, California ISO and utilities buying the power know. Brightsource and NRG aren’t saying, and as they are holding a commissioning ceremony on February 13 they are keeping silent in the interim.

California ISO does show a big increase in output from solar thermal electric plants for the first five days of February, which could also lead observers to believe that Ivanpah has come online. And this would be proof, except that there are other solar thermal electric plants (also called CSP or concentrating solar power) plants in California, including the 354 MW Solar Electric Generating Systems, the first large-scale CSP plants to come online in the world in the late 1980s and early 1990s.

To further complicate matters, January ISO data shows practically no CSP output during nearly all days in January, meaning that neither SEGS nor Ivanpah were what we would call operational.

Operational or non-operational?

California ISO does provide more clues to this mystery. The organisation keeps a list of “curtailed and non-operational” power plants, and Ivanpah’s three units have been on this list for months. During four of the first five days of February at least one unit was listed as fully curtailed or non-operational and the other two partially curtailed.

The position of the three units have switched on this list. On February 2, it was unit 2 that was fully offline, with the other two partially restricted; and on February 3, 4, and 5, unit 3 was fully offline. On February 1, all three units are listed as only partially “curtailed or non-operational".

So in the end, we simply don’t know how much power is being produced by Ivanpah at this time. It is likely that as the units ramp up for full production, one or the other is being taken offline for technical tweaking.

I’m willing to wager that construction contractor Bechtel and Brightsource are making one hell of an effort to get everything up and running for next week, when Energy Secretary Ernie Moniz flies out from DC for the big unveiling. Around February 13 we are likely to see a big jump in solar power output in California.

Or not.

Originally published on CleanTechnica. Reproduced with permission.

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