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Solar Revolution? Don’t Hold Your Breath.
The $2.2B Ivanpah Solar Power Facility is in the news and in danger of closure for underperforming on its contracted power production. If you are a Ricochet reader, you are probably not surprised, but early results from Ivanpah and two other large scale solar power installations — the Desert Sunlight and Topaz plants, which are also located in Southern California — do not bode well for the future of solar as a replacement for fossil fuels or nuclear power. (Ivanpah’s predilection to burn up birds has been covered on Ricochet previously so I’ll skip it).
Solar has offered the promise of nearly limitless carbon-free energy for nearly 40 years, with a few caveats. First, solar power is expensive but prices per kilowatt are falling rapidly and approaching that of traditional plants. Second, size matters, which means that solar will need to be scaled-up from boutique rooftop installations to larger plants that can produce power at a cost on par with other forms of power generation. This is all done, of course, with the advantages offered by federal loan guarantees specifically designed to prove-out the scalability of these concepts so that the private sector can take over.
In the words of Peter Davidson, solar panels “… existed before as a technology, but that technology hadn’t been deployed at a large scale. Once we’ve done that, the government steps aside let the private markets take over.” However, results from these demonstrator plants appear to show that they are not cheaper than even nuclear plants — which are very expensive — even when scaled-up to large size. The line of companies waiting to take over without federal loan guarantees will be a short one.
(Before beginning a technical discussion, a brief explanation for the uninitiated, a watt is a measure of power, while a watt hour is a measure of energy consumption; they are, roughly, analogous to speed and distance travelled. A megawatt is a million watts and a gigawatt is a billion watts.)
The 392 megawatt (MW) Ivanpah plant is unusual in that it focuses sunlight from over 170,000 mirrors onto three 450′ tall towers (see picture above). The towers contain boilers that create steam, which drives a turbine. The Ivanpah plant’s ability to concentrate solar power was specifically conceived to address the scale-up issue. It opened in 2013 and has underperformed on its expected 1,000 gigawatt-hours (GWh) per year of power ever since.
How badly? First, let’s consider Ivanpah’s capacity utilization, which is the amount of power produced divided by the nameplate power (i.e., its gross capacity). If Ivanpah ran around-the-clock for a year at nameplate power production rate of 392 MW, it would generate 3,433 GWh of energy and its capacity utilization would be 100 percent. This is impossible for several reasons, and its utilization was predicted to be 29 percent (or about, again, 1,000 GWh). That proved to be wildly optimistic: in reality, Ivanpah produced 419 GWh of power in 2014 and 652 GWh last year, or about 12% and 19%, respectively, of its capacity. One can easily see why power contract cancellations loom over the plant.
Two other large solar plants have also been completed in southern California during the same time as Ivanpah. The Topaz Solar Farm (who could hate a solar farm?) in San Luis Obispo County and the Desert Sunlight Solar Plant in Riverside County each have a nameplate power output of 550 MW and both began operation in 2013, so we have two full years of operating experience to look at. These two plants use photovoltaic (PV) panels like those you see on houses. There is not a huge economy of scale in scaling-up PV, because they are just like a rooftop solar plant a million times over.
Although these plants still do not have the nameplate power of a world-class power plant fueled by nuclear, coal, or natural gas, they are roughly ten times more powerful than what was available a decade ago. And as Mr. Davidson said above, this scale-up was specifically meant to prove that solar can be scaled up to commercially viable size. After two full years of operation the annual capacity utilization of each plant maxed out at about 27% in 2015 (this was much better in each case than 2014, which I guess was a bad year for sunlight all around). Better than Ivanpah, surely, but how well do these state-of-the-art solar plants to other plants?
In the chart below, I compare the capital expenditures, size, and capacity utilization of these solar plants with a pair of nuclear plants which are under construction. I picked nuclear because they’re expensive, (essentially) carbon-free, and because — like solar — most of the costs are upfront (in contrast, fossil-fuel power plants have relatively low sunk costs, and much of the cost over the plant’s life cycle is associated with buying the coal or natural gas fuel). As such, I picked the two new reactors at the Vogtle plant in Georgia. These reactors will use newer Generation III pressurized water reactor (PWR) technology which incorporates, among other things, passive safety features to avert a meltdown and much less design complexity which saves cost and improves reliability as when compared to older reactors. Vogtle’s new reactors are projected to run several billion dollars over budget and are not yet complete. In order to give solar the best advantage, I have used the cost estimate with overruns here below:
| Plant | Type | Capex ($B) | GW (gross) | Cap. Util. | $/GW | $/GWh |
| Topaz | Solar (PV) | $2.40 | 0.55 | 27% | $4.36 | $16.16 |
| Desert Sunlight | Solar (PV) | $2.30 | 0.55 | 27% | $4.18 | $15.66 |
| Invapah | Solar Tower | $2.20 | 0.39 | 19% | $5.61 | $29.56 |
| Vogtle 3 & 4 | Nuclear (PWR) | $16.40 | 2.50 | 88% | $6.56 | $7.45 |
So you can see that when a simple $/GW of nameplate capacity metric is used, solar compares well with nuclear. The Desert Sunlight solar plant cost $4.2B/GW of capacity which is substantially less than Vogtle 3 & 4, which together are $6.56B/GW. Not surprisingly, these numbers are frequently used by solar boosters. But as anyone who’s ever stepped outside and has a brain can tell you, the Sun provides its power unevenly throughout the day and throughout the year. When you normalize the cost of the plant by the power actually produced, (i.e. divide capex by GW hours actually produced in a year), you get a very different result: the nuclear reactors cost about half as much to operate as the PV plans, which cost about half as much again as Invapah.
And remember, these solar plants are in nearly ideal locations, having high elevations, clear skies, and relatively southerly latitudes; identical plants in Ohio or New Jersey would perform far below this already-disappointing production. (For the record, the $B/GWh numbers should not be confused with the actual cost to produce power, though that measure has similar units. The numbers I am showing would be the payment required to pay back the capital expenditure in a single year, which is only used to normalize costs by capacity utilization).
So, you can easily see you can’t compare the costs of solar and nuclear without some complexity: Ultimately, the amount of power produced is important when capacity utilization numbers are as low as they are for solar power, and the grid is going to have to depend on other plants to back up the solar power when the sun isn’t shining and those plants have to be paid for also. The cheapest way to do this, is to pay fossil fuel plants to be on standby for when they are needed to fill in. If you’re concerned with carbon emissions, that should be a deal breaker, especially if you’re operating where coal is the fossil fuel of choice.
The upshot here is that several large-scale solar demonstrator plants have been built and operated for years now. The results show that there continues to be large gaps that need to be filled before solar can compete with nuclear plants (and larger gaps yet if it is to compete with fossil fuel plants). Scaled-up photovoltaic plants are easily twice as expensive as nuclear plants when judged by the power provided and the solar tower plants appear to be worse than photovoltaic in every way.
As a policy prescription, the United States should probably re-think offering loan guarantees for large solar power ventures (at least 17 of which have been funded in this way). Instead, the government would likely get a much more for its money by funding research into improving photovoltaic panels or Generation IV nuclear technology demonstrator plants which could be cheaper, safer, and even proliferation proof than today’s nuclear plants. But more about that another time.
But don’t hold your breath.
Published in General
Forget about the dollars. What about land consumption.
NYC consumes roughly 145,000 GW-hr of power per year. This means we would need nearly 300 Ivanpah plants just to satisfy this one city. Ivanpah covers a little over 6 square miles. 300 Ivanpah’s would cover over 1800 square miles. NYC’s land area is roughly 300 square miles. So the power plant would have to be about 6 times bigger than the city. Does anybody think this is realistic.
This assumes there is no inefficiency in transmission and a storage system is invented so they can have lights at night.
The logic and math are pretty simple. You don’t have to be an engineer to see that solar cannot satisfy our energy requirements. A similar calculation gives even worse results for wind power.
The only choices known, at this time, are nuclear or fossil fuels. Going away from them for wind or solar is folly.
Sad, I recall hearing a few decades ago that Canada’s number one export was electricity. Sounds like those days are over.
Was that hydropower?
Dan, Governments don’t pay subsidies, taxpayers do.
How is it that these “sustainable” forms of energy are so bad for the creatures living in their environment? Wind turbines are notorious for chopping up birds and other flying creatures and this Ivanpah Solar Power Facility incinerates them. Not to mention the terrible eye sores they are. The free market does not support these things for a reason.
I don’t mean to say it is insignificant, but traditional power plants whether coal or nuclear use massive amounts of water for steam generation and cooling. Which is one reason why the plants are almost always found along rivers or the ocean. I suspect water consumption at these plants is several orders of magnitude more than water consumed to clean solar panels although that is just a guess on my part.
Ever walk barefoot in the Mojave at mid-day in the summer? Hot, yes. So, does the dust makes that much difference?
Yes, and so does the wind in terms of “cleaning them”.
The early Mars rovers used solar cells/batteries for their power source, and thus were only active during the daylight periods. As they aged they lost both cell efficiency, but also were getting more than expected degradation from dust covering the arrays.
Until a big wind storm occurs which then “blasts” the arrays clean and the rover would get a boost in total energy collection until the dust would slow reduce the capacity again. Same thing happens on earth, deserts have no shortage of dust.
Water used for cooling is not water than anyone misses. The Columbia river, to take on ridiculously extreme example, flows a massive amount:
That is a very large number, indeed.
“The $2.2B Ivanpah Solar Power Facility is in the news for being in danger closure for underperforming its contracted power production. ”
I’m getting tired of seeing egregious violations of English on the main feed.
If you can’t edit it right, don’t edit it at all.
Very interesting and thanks. Clearly solar has not gotten to be efficient yet. I can understand having them on roof tops to offset traditional energy generation, and I much prefer them over those silly wind mills, but it seems to me that these large solar farms are environmentally unfriendly. Doesn’t one alter the habitat and the nature of the terrain just by the continuous shadows cast by the panels?
We’ve known from the beginning that because of transmission losses cancelling out incremental increases in PV efficiency, scaling was a lost cause. The argument was that solar concentrators might be efficient under some circumstances, and this argument has just been proven wrong.
It seems to me that the only sensible way to harvest solar is the opposite of scaling up, that is, widely distributed “boutique” site-specific installations after PV yield efficiency has seen substantial, not incremental, improvement, and backed up by next gen nuclear base load.
That means research that goes back to the physics; one photon releasing multiple electrons rather than one, etc. PV has some promise, but we should be doing only basic research right now, not trying to push technology into the marketplace when it is decidedly non-competitive.
No arguments from me.
This technology was not ready for broad commercial implementation, and it was fairly clear on paper before being built. If you can not get truly innovative technologies funded that have a clear advantage with venture capital, but only though government largess, well there is some laws of economics at work here as well….
As Adriana Harris said, Ivanpah is a bird slaughter facility. Any bird that flies over it gets incinerated by the focused sunlight. The Justice Dept. fined Exxon/Mobil $600k for killing 85 birds over 5 years. Ivanpah kills 28,000 birds a year and nobody says a word.
http://www.coyoteblog.com/coyote_blog/2014/08/equal-protection-under-the-law.html
And follow his link at the bottom of that post for comments on bird slaughter with wind power.
You and Pony Convertible both hit the same issue. Solar will/would require massive amounts of land consumption once scaled up. Using the 6 sq. miles of Ivanpah and its nameplate capacity (i.e. disregarding the point that the capacity factors are low on solar plants) one would need 16,000 sq. miles of Ivanpah’s to replace the roughly 1,000 GW of US generation capacity. This about 40% of Indiana.
Add in a 27% capacity utilization to that and you get to 60,000 sq. miles which is about all of Wisconsin. But even that does not do it because you still need massive backups for when it is not sunny.
Will there be any complaints about habitat loss? I would think there would be.
I think you are right, that Solar can be helpful as distributed generation providing supplemental kW during peak periods which also takes strain off the transmission grid (a twofer if although an expensive one). But I doubt it gets much better than that. These scale up solar plants appear to be a slow motion disaster.
Ross mentioned “dispatchability,” but another problem with wind/solar is frequency control. The electric grid relies partly on big, heavy rotating machines to keep the frequency very close to 60 hz. As the fraction of power provided by wind and solar increases, the need to compensate will also increase. This cost is never factored in.
The error here was mine and I apologize both to Ross and the membership.
Don’t apologize for being human. Sheesh, it was a meaningless error that I didn’t even notice.
It was not a meaningless error. It made the sentence complete nonsense, and it was on the main feed, at the top of the article, where everyone could see it.
I think editors have a lot on their plate. It would not hurt to have a clever high school student available to read the article aloud before it hits the main feed. Or a member with some time on his or her hands to do light proofreading. In general, the quality of the editing here is good, but this is not the first time that members have pointed out problems.
Funny, I was able to decifer the Sanskrit the sentence was apparently written in. So were most of the commenters prior to you. Give the editors a break.
We’ll agree to disagree. I say they have a job, and they need to do it.
I did not notice it and, all and all, the post reads much better than it did before you edited it. However, it is now public knowledge that neither you and I are perfect.
Not everyone can be like me, you are forgiven.
:D
Damn, that should have been you “or” I.
Cheers right back.
I take it back. I was perusing a Wikipedia article on a plant similar to Ivanpah in Morrocco and I came on this….
The design uses wet cooling and the need to regularly clean the reflectors means that the water use is high — 1.7 million m3 per year or 4.6 liters per kWh.[11] Water usage is more than double the water usage of a wet cooled coal power station and 23x the water use per kWh of a dry cooled coal power station
News:
Heh
Not like it provided much electricity anyway. . .