World’s Largest Solar Thermal Power Plant Delivers Power for the First Time

http://www.technologyreview.com/view/519596/worlds-largest-solar-thermal-power-plant-delivers-power-for-the-first-time/

by jes • 13 years ago

74 77 13 years ago

chime• 13 years ago

The article claims a high cost of mirrors and steam turbines as the big negative. Without seeing the cost-breakdown of the entire project, it is hard to ascertain if materials are indeed the largest factor or if it is something else like labor/salary or technology/licensing. If it costs $200m to build the tower and buy turbines, $2B/200,000 mirrors = $10,000/mirror. I find it hard to believe that cannot be lowered drastically once the research phase is over.

While I feel Solar Thermal (more appropriately CSP http://en.wikipedia.org/wiki/Concentrated_Solar_Power ) is very promising, for some reason many don't. Google invested in this company ( http://www.google.org/rec.html ) but has stopped investing more into CSP, preferring photovoltaics ( http://www.evwind.es/2011/11/24/google-cans-concentrated-sol... ).

raverbashing2• 13 years ago

The article reads biased, exactly because of the points mentioned

What else uses steam turbines? Coal plants!

My bet is that the high cost is in the primary(?) heat circuit, the one that runs on molten salt

Also, it looks like it's still one of the first designs, so it's bound to cost more.

ndonnellan2• 13 years ago

Ivanpah is steam, not salt (in salt plants, the storage system is a large component of the cost).

It's not quite as simple as which area is the biggest cost component; in my experience everything adds up. You see that giant structure next to the tower? That's an air-cooled condenser, much more expensive than a wet-cooling tower, but doesn't use any water. Wouldn't surprise me if that one component cost >$50m.

For the record, power towers have been around since at least the 1980s; the technology isn't super novel, but it's all in the cost reductions since then.

danielweber• 13 years ago

I read the comments first, and was expecting some very negative article.

It's not. It talks about both the positives (this is solar power that can run at night) and the negatives (it's expensive).

pjc504• 13 years ago

I feel that's probably a low number for the cost of turbines; turbomachinery is always very expensive.

The mirrors are "heliostats" that turn towards the sun. So they have a set of motors and control electronics which will be a large part of the cost.

ams6110• 13 years ago

Agreed, turbines are precision mechanical devices and also need regular maintenance. High-pressure steam is aggressive stuff so all the plumbing needs to be built accordingly as well.

jws• 13 years ago

You can do a pretty nifty heliostat with passive heat collectors and a closed loop containing a fluid which vaporizes at a convenient temperature for shifting the center of gravity. (And dampers so wind buffeting doesn't jiggle the panel too much.)

That said, $30 of motors and $50 of controller board is probably cheaper and more accurate. The passive system is good enough for orienting solar panels, probably not for aiming a mirror.

xutopia• 13 years ago

Photovoltaics is more inline with Google's needs because it also offers increased cooling if placed above data centers. Could this be a reason why they favour PV?

fludlight2• 13 years ago

Three reasons why PV works better for rooftop:

1.) Thermal only works on a massive scale. You can't fit 1000 large mirrors, a tower, a huge turbine, and the requisite plumbing on a commercial rooftop.

2.) Even if you could, the city wouldn't let you because the mirrors would distract aviation and anger neighbors.

3.) Technological advances and a capacity glut in PV manufacturing brought the price of panels down so far that it doesn't make economic sense to build thermal anymore.

redwood2• 13 years ago

A reality in California is the high cost of regulatory siting. In this case the desert tortoise issue was costly.

In many other cases, you see multi-year court battles (some in regulatory proceedings rather than traditional legal courts). A lot of the time those pushing the fight are not environmentalists but rather NIMBYs who use the laws/regulations to try to prevent progress. Same with High Speed Rail, of course.

The delay and uncertainty adds a higher-than-expected cost since the investment appeal erodes.

It's interesting that California's pro-environmental laws can sometimes be a hurdle to "green" projects in this sense. Different sides of the environmental issue spectrum.

jonah2• 13 years ago

Finding and relocating all the tortoises and keeping an eye out for missed ones while the construction was going on is expensive but not relative to the total project cost.

Source: My uncle does this work and was on this project.

fludlight2• 13 years ago

Environmental concerns about displacing protected wildlife can be mitigated by installing relatively inexpensive things. Ditto for concerns about displacing low-income families. The real problem is that electricity in California is cheap and it is impossible to build a profitable utility-scale solar farm without monetary government incentives or a down-round. The former is winding down and the availability of the latter is constrained by a negative feedback loop.

The expiration of federal, state, and utility incentives, mainly ARRA Section 1603, really screwed up the solar market in most of the US. Uncle Sam used to give developers of renewable projects (solar, wind, geothermal, biomass, hydro, etc) 30% of the total cost of the project in cash within a month or two of completion. Congress refused to renew that program after Solyndra, even though it was probably responsible for building several nuclear generators worth of renewable capacity. Companies can still get tax credits, but these newly-formed single-asset corporations that typically own the farms don't have any tax liability to offset. They can monetize the tax equity by doing some screwed up partnership flip structure, but that is time intensive and costly.

States also used to have incentives which ranged from state tax credits to RECs. These tax credits are even harder to monetize since now you need to find an equity partner who has a multimillion dollar state tax liability in, say, North Carolina. The market for RECs collapsed right after the utilities came close to meeting their renewable portfolio standards.

Most of the current pipeline of utility scale projects in the continental US involves a cramdown of the initial investors and developers. Everyone is looking for "broken" projects where someone else already spent the time and capital to get the project shovel ready. At the smaller end, there are even some contractors who financed the construction loans themselves and are being crammed down by the takeout guys. At the same time, many lenders have discontinued new lending and monetizing tax equity is expensive and difficult.

There are some exceptions such as Hawaii where 90% of their electricity is generated from oil so electricity prices are sky-high (think 5x+ California), but the local utility can't keep up with the requests for permits so projects wait in an ungodly long queue.

adrianN• 13 years ago

How can it be more expensive to produce a mirror than a solar panel? This doesn't need astromony grade mirrors... Are steam turbines so expensive compared to inverters?

wlll• 13 years ago

The cost does seem rather high, I wonder if (as a DOE funded project) contractors or suppliers were massively overcharging knowing that the money was there to do so.

rwmj• 13 years ago

I guess it's not the mirror, but all of the motors and electronics that keep the mirror pointing in the right direction. If only the Sun didn't move around the sky, this would be very cheap!

Shivetya• 13 years ago

Does anyone have information on what type of system could be setup using photovoltaics across a similar 3500 acre site? While its obvious not all the acreage is used for mirrors I am curious as to difference is possible output.

Output is expected at 392mw. I found a few acreage references for coal/gas plants but their output many times one of these plants. One solar plant I found is 25mw using about 250 acres.

Just trying to understand the land use efficiency versus other solutions. Fossil fuel plants do not count usage of road/rail in their size calculations nor the size of the source of their fuels. (coal mines/pits/etc)

chiph2• 13 years ago

What's the reflectance of a PV panel? Wondering if the mirrors could be replaced with them, knowing they aren't as good of a reflector as a mirror, but perhaps they reflect enough to run the steam generator, and still produce power themselves. Net win, perhaps?

debacle5• 13 years ago

If you could diffuse the spectrum, you could reflect the IR but absorb the UV.

Not being a physicist, I don't know what that would entail.

jes3• 13 years ago

Do solar sites ever use mirrors and PV panels, in combination?

tlarkworthy• 13 years ago

Latest PV kinda use mirrors internally

_mulder_4• 13 years ago

Do you mean, concentrating sunlight onto PV? or Having PV cells that are also reflective?

Reflective PV cells/mirrors wouldn't work well as you're taking the energy out one way or another. The more you reflect, the less you can use for PV, and vice-versa.

jes3• 13 years ago

Sorry for being unclear. I meant concentrating sunlight onto existing PV panels. I suppose that I'm assuming mirrors << PV in terms of cost.

tonylemesmer2• 13 years ago

How do they keep the mirrors clean? How do you keep solar panels clean for that matter? Must require quite a bit of upkeep.

_mulder_4• 13 years ago

Like this.. http://www.youtube.com/watch?v=zLogKN80plY

tonylemesmer2• 13 years ago

Ha! interesting. Sand and shiny mirrors don't mix very well.

api2• 13 years ago

Any lifetime cost calculations must factor in the fact that the fuel is free. I've seen quick comparisons with combined cycle gas, coal, etc. that neglect this obvious difference.

_mulder_4• 13 years ago

api, this is a great point and one that is often overlooked with most renewables vs non-renewables cost arguments. However, when you compare $/kwh of the electricity it does take all of this into consideration.

api2• 13 years ago

I think of renewables' higher cost as basically paying up front for the fuel instead of over time. At least that's how it should be thought of economically.

debacle5• 13 years ago

I wasn't aware we were building these solar towers in the US. How does this compare to the solar updraft ones being built in Australia? It seems like the solar chimney design is more simple, however there are obvious efficiency concerns (kW/acre).

_nate_• 13 years ago

I was going to bring up the same point. The solar updraft systems seem to be more cost effective and generally easier to build. I don’t understand why they’re not being built more. However, they definitely take up more land. And nature advocates claim they are harder on the environment because they essentially bake the top soil, killing everything (which is probably true). But everything has trade offs.

http://en.wikipedia.org/wiki/Solar_updraft_tower

debacle5• 13 years ago

It looks like the solar updraft systems are only cost effective when you have vast amounts of cheap/free land - they are very inefficient in Watts per square meter, getting around 1% efficiency compared to 20-35% for other systems.

danbruc• 13 years ago

When you calculate the amount of power the plant is likely to produce over its lifetime, the cost per kilowatt-hour is likely to be much higher than for fossil-fuel power. It’s even likely to be higher than the cost of power from solar panels, thanks to the fast drop in solar-panel prices in recent years. If costs don’t come down — and decreasing the costs of mirrors and steam turbines is hard to do — solar thermal power might prove to be a dead end.

I hate this attitude - the costs of the produced energy is not everything. Who said that energy has to become cheaper and cheaper? If you want to reduce the carbon dioxide emission just introduce additional taxes for fossil fuels or even prohibit burning them or subsidize solar energy. Just accept the increased costs and enjoy your clean air.

grannyg00se• 13 years ago

I hate it as well, but I think it is generally anticipated that any greentech solution is never going to be widely adopted until it achieves price parity.

cinquemb• 13 years ago

Another thing that people often don't price in to the cost effectiveness of petroleum fuel sources are the many increasing billions that went/go into acquiring said fuel every year…

fooqux• 13 years ago

I'm not entirely sure I believe this myself, but I'm sure one can easily find studies describing the increased healthcare costs of the entire US population due to fossil fuel burning.

But I think it shouldn't be looked at in that light. The US government claims we, as a first world country, have the responsibility to protect those less fortunate than us. While that line is normally used to justify wars in far off countries (that just happen to be oil-rich), things like this are what I think of. Besides, it's not so much the pollution the US generates that scares me. It's places like China (or the next country that suddenly finds itself in a rampant industrial age) that scare me. Global pollution does not respect political boundaries.

So yeah, this will be more expensive at first. But the research needs to be done before it will get better. Somebody has to take lead so it can be ready by the time more 3rd world countries get "uplifted".

e12e2• 13 years ago

Which is another way to say that we won't start using "green" energy until we run out of hydrocarbon fuel.

It's a very dangerous attitude -- we need to use what's left of hydrocarbon fuel to bootstrap new energy while we still can, and have the luxury to afford to experiment.

I forget where the quote is from, but as has been said: "The definition of modern agriculture, is that it is a way to transform hydrocarbons into carbohydrates.". Unless we do something soon, running out of oil, will mean running out of food. We need it for tractors, and for modern fertilizers, for irrigation -- and for transport of food.

Oil (and coal) is cheap energy, because it's basically just laying around, waiting for us to burn it. It's grown harder to get -- but it is ridiculous to wait around for other energy to "become cheaper". If we don't make an effort to change the entire infrastructure the world runs on (quite literally) -- what will happen is that oil will become as expensive as "green" energy -- not the other way around.

And that is of course ignoring all the problems hydrocarbons leaves us with, in the form of various forms of pollution. That we'll have to clean up and/or deal with without cheap energy.

reedlaw• 13 years ago

Just accept the increased costs and enjoy your clean air.

That's easy to say, but shouldn't we use existing costs as a base metric for measuring how much increased costs we can bear? Otherwise we would have to accept energy costs that eclipse the cost of everything else--including basic living expenses. Of course, energy cost is tied to basic living expenses, so at some point higher energy costs would mean fewer people can afford to live. Therefore, clean air has to be balanced with the more basic human right to live.

pjc504• 13 years ago

Lack of clean air can also _impair_ the right to live. When coal was the default source of domestic heating in London, toxic smog frequently caused hundreds of deaths and generally caused respiratory diseases.

ajuc• 13 years ago

Who said that energy has to become cheaper and cheaper?

It needs to if we want to have better living standard in future. Or even more or less equal living standards for all people on Earth. Which I think is a reasonable goal.

If the power is expansive poor people won't use it. Energy is one of the most important productivity multipliers there are. Forbiding developing countries access to reasonably priced energy means artificaly keeping them poor forever.

zurn• 13 years ago

I hate this attitude - the costs of the produced energy is not everything.

Put another way, for apples-to-apples you have to compare against the real cost of fossil fuels (including externalities).

sdoering• 13 years ago

Does anyone have information on the water-consumption (steam-loss, cleaning the mirrors, cooling the mirrors, and so on)? I would really love to see, if this is a feasible method of producing energy in areas without that much water.

But I really lack the necessary numbers in terms of consumption of water, to built an idea, if this is a viable technology for deserts and other dry and sunny places on this planet.

bjz_2• 13 years ago

When you calculate the amount of power the plant is likely to produce over its lifetime, the cost per kilowatt-hour is likely to be much higher than for fossil-fuel power.

Solar thermal is cost effective if you take into account the economic problems that carbon emissions cause over their lifetime in the atmosphere. This is why putting a price on carbon emissions is so essential: to expose the true cost of fossil fuels at the time of sale.

jes3• 13 years ago

Perhaps a nice benefit of these plants, presumably, is that your operating costs don't change much due to changes in fuel costs (your fuel is free) and these plants ought to be somewhat easier to site / approve than a nuclear plant.

bjz_2• 13 years ago

The other benefit to these plants over nuclear is that the time it takes to get them operational is much shorter. This allows for faster iteration time, and therefore more opportunities to improve the technology and reduce costs.

jpadkins• 13 years ago

So how do you come up with a fair price to capture the carbon externality?

And do you add the externalities to green power like solar? More people have died installing solar equipment than all nuclear accidents. Or what about environmental damage during PV manufacturing? Do we add those to the price of solar at the time of sale?

derobert• 13 years ago

Indeed, it's difficult to exactly price externalities. There are published estimates of the carbon externality. You do you best; it's far better than the "estimate" we currently use ($0).

When comparing, you add in the externalities to everything. To be specific:

- you don't count the deaths in PV installation as its not an externality. The installers are an involved party; they can (for example) ask for higher wages due to risk. (Also, if you wanted to compare this to nuclear, you need to include deaths building those nuclear plants as well. And possibly mining the uranium.)

- you do count the environmental damage during PV manufacturing (and turbine manufacturing, and coal mining, and oil drilling, etc.)

ajays2• 13 years ago

Steam turbines have been around since 1800s. The tech is well understood. Mirrors are also cheap. These two can't be the reason for the high cost.

My guess is that the fancy molten salt stuff drove up the cost. Molten salt is very corrosive.

I would _love_ to see the breakdown of the costs.

Aside: I drove past the plant this summer, and even from the highway it looked awesome.

pjc504• 13 years ago

The official fact sheet http://www.bechtel.com/assets/files/Renewable_%202013_Ivanpa... makes no mention of molten salt, just a regular boiler on top of the tower.

ferdo3• 13 years ago

The biggest flaw I see with this solar project is that it's just another continuation of the centralized model. We should be encouraging homes and businesses to be producers of energy and decentralize our power grid.

$2 billion on a centralized project in the age of increasing decentralization seems like waste of money.

tlb• 13 years ago

I've heard various arguments for this, none of which seemed that convincing. Centralized power generation seems like one of the great successes of the 20th century. What do you think the advantages of decentralization are?

ferdo3• 13 years ago

Centralized power generation seems like one of the great successes of the 20th century.

From the point of view of large producers and investors, sure. Tesla's idea of decentralized power was viewed as pie-in-the-sky by his benefactor, JP Morgan.

I wouldn't call nuclear power a success story.

e12e2• 13 years ago

the age of increasing decentralization

While I'd love to see more decentralization, that's not really what's happening, is it? Urbanization is AFAIK stronger than ever, fewer grow their own food (or even have the ability to do so), institutions are getting more centralized, not less...?

We're even breaking the Internet, giving people asymmetric connections forcing them to depend on centralized services -- so what exactly are we decentralizing?

ferdo3• 13 years ago

what exactly are we decentralizing?

In another generation or two, people will have the ability to design and print their own circuit boards. Technology itself is becoming decentralized which will have the longterm effect of decentralizing society.

Less than 200 years ago, railroads were the height of technological achievement and the most powerful centralizing force in society, industry and government.

grecy• 13 years ago

For years there has been talk of building a 1km "solar tower" in my home town.

The basic plan is multiple square kilometers of greenhouses surrounding a 1km chimney. The air inside the greenhouses will heat up and rise up through the tower at high speed. The bottom of the tower will be filled with 32 generators, for a total of 200MW.

http://enviromission.com.au/EVM/content/home.html

I still hope they build it.

benkillin2• 13 years ago

This is called a solar updraft tower (I like to call it a solar chimney): http://en.wikipedia.org/wiki/Solar_updraft_tower

World’s Largest Solar Thermal Power Plant Delivers Power for the First Time

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