Clean Power

Published on July 6th, 2013 | by Giles Parkinson


Concentrated Solar Set To Change How We Think About Energy Sources

July 6th, 2013 by  

This article first appeared on RenewEconomy

The 110MW Crescent Dunes Solar Energy Plant, a concentrated solar power project due to be completed in Nevada early next year, will not just be the largest solar power tower plant with fully integrated energy storage built – it could also challenge the way the world thinks about renewable energy. Or even energy sources in general.

The $1 billion Crescent Dunes project near Tonopah in the Central Nevada Desert, some 300kms north of Las Vegas, was developed by the Santa Monica-based SolarReserve and features the company’s market leading molten salt power tower technology with fully integrated energy storage.

Screen-Shot-2013-07-04-at-9.00.15-AMWhat makes it unique and a potential game changer in the electricity industry is the flexibility and dispatchability of its power, meaning that it can deliver electricity whenever it is needed by customers; and its cost, which already beats diesel, is competitive with new build coal and gas generation.

The Crescent Dunes facility will have 10 hours of molten salt storage, which on average will allow it to deliver 110MW of baseload capacity to Las Vegas between the hours of 12 noon and midnight each day, when the city needs it most to power the lights and air conditioning of its casinos and entertainment palaces. It has signed a 25-year power contract with NV Energy, Nevada’s largest utility, to  do that.

Tom Georgis, SolarReserve’s senior vice president of development, says the unique capabilities of the technology means that the plant could have been configured in any number of ways. With a 180MW turbine, for instance, it could have produced power for 10 hours each day, which was the original intention. With a smaller turbine, and more than 20 hours storage, it could have delivered 50MW of base-load power 24/7.

In the end, Nevada pitched for midday to midnight to suit its needs. In effect, the plant is providing baseload power for a fixed period each day – delivering the benefits of coal-fired power without the downsides, which is of course heavy pollution and an ability to be switched off at will or at regular intervals.

‘You can’t do that with a coal fired facility,” Georgis says of the Nevada contract. But the technology also allows it to compete with gas-fired generation, both in the ability to provide baseload and as a peaking plant.

Next year, SolarReserve begins construction of the 150MW Rice Solar Energy Plant in Southern California, which will act more like a peaking power station to suit that state’s needs. Proposals the company will take to Chile, Australia and the Middle East will likely be for baseload power. (We will explain more about those plans in the next two days).

“This should be the winning technology. It has all the attributes you looking for to displace conventional generation,” Georgis says. “It’s not just fulfilling renewable energy targets, you are displacing any new build fossil plants – from nuclear, gas and coal. This is going to change the discussion in energy markets, certainly around the idea that renewables are variable.”

Georgis says there is a lot of confusion about storage and what it means. He says the way to think about it is in the amount of electricity produced by a solar tower plant over a year.

With the standard “S-Class” configuration of the plant, the design being built at Tonopah, the plant can produce over 500GWh of electricity a year in strong solar locations such as Western Australia and the Southwest USA. That can be sliced and diced whichever way a customer – be it a utility, industrial group or a miner – chooses. And that can be in 24/7 base-load, delivering electricity at specific times of the day as in Nevada, or as a peaking plant.

“We are not just a renewable energy generator, we can integrate and help firm and shape other variable energy sources,” Georgis says. ”It will run in summer for 16-18 hours a day. But I can turn down the turbine and run it 24/7 if the utility asks me to do so.“

To emphasise the point, Georgis points to the following graphics that show the output from a solar PV plant, and a solar tower plant without storage. The big square blocks – coloured green and yellow – are two output scenarios from the tower with storage, but it can be reshaped and timed to suit the customer’s needs. Grid operators and many customers like big square blocks.


See our explainer to see more about how the technology works.

The other key point, and this is the critical one, is in price.

The Nevada project has a publicly disclosed power purchase agreement of $US135/MWh with NV Energy. The project is supported by cheaper finance from the Department of Energy Loan Guarantee Program, and tax incentives, but Georgis says it is also the first of its kind to be built at this scale and has extra margins and contingencies typical of a first plant.

For this reason, Georgis says $135/MWh should be viewed as a reasonable estimate of costs, because by the time the fourth or fifth plant has been constructed, the capital costs will have come down dramatically.

Georgis says that even without incentives, the LCOE would be “well south” of $200/MWh. In Chile, where the excellent solar resources means that the output is 40 per cent greater (around 700GWh a year), the price is already at $135/MWh without any incentives.

“By 2020, we should be south of  $100/MWh (in the US, Australia and elsewhere) and not reliant on any type of government subsidy or incentive program”, he says. That is key, because as Bloomberg New Energy Finance noted, new coal fired and gas fired plants are already more expensive, and will be well north of that figure by 2020.

And Georgis says the generation facility can participate in any kind of energy market. “If you have a flexible dispatch market, a storage market, or a capacity market, it can participate in all of those. It can even play in the merchant market with a robust price,” he says.

The Crescent Dunes plant will not be the first of its type, but it will be the biggest to date, and the first built to what Georgis describes as “utility scale”. The 18MW Gemasolar plant (pictured) has been operating in Spain for the last 18 months, and the 10MW Solar Two demonstration facility near Barstow in California’s Mojave Desert was operated by the Department of Energy in the 1990s.

SolarReserve has the exclusive worldwide license to the technology which was developed by Rocketdyne, a subsidiary of Aerojet, and perfected during various space programs. These include the algorithms for the solar trackers that move the heliostats, and the receiver, which uses proprietary metallurgy technology that allows it to expand and contract, and to resist melting.

The company currently has 7 projects in various stages of development the US, two of which have power purchase agreements (Crescent Dunes and Rice), and six projects in Spain, including one (the 50MW Cinco Casas project) with a PPA, although the Spanish projects are not progressing at the moment because financing is difficult to obtain in the current market. SolarReserve is pursuing contracts in Chile, South Africa, North Africa, the Middle East, China and Australia.

(Tomorrow, SolarReserve talks about its plans for Australia).

Check out our new 93-page EV report, based on over 2,000 surveys collected from EV drivers in 49 of 50 US states, 26 European countries, and 9 Canadian provinces.

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About the Author

is the founding editor of, an Australian-based website that provides news and analysis on cleantech, carbon, and climate issues. Giles is based in Sydney and is watching the (slow, but quickening) transformation of Australia's energy grid with great interest.

  • Sam Hopes

    In line with their ambitious Jawaharlal Nehru National Solar Mission, the Indian government has recently announced plans for what could become the world’s most powerful solar plant.

  • Steeple

    If I can ask a question, what do people here feel are the most promising technologies in the demand side that can materially help us shed load economically? LED lighting seems to be a clear leader, but I would appreciate hearing other thoughts.

    • Bob_Wallace

      Perhaps improvements in air conditioning. There’s the Ice Bear storing of cold which doesn’t let us shed load as much as even out load and move demand to when we have spare capacity.

      There are also improvements in AC for humid zones via desiccant systems which should lower demand.

      Obviously insulation and heat blocking. These are very low hanging fruit.

      Appliance and electronics efficiency. We really need an efficient generation of set top boxes/TV recorder stuff.

      For the most part I think there are major load shedding opportunities which are which are pretty low tech. As smart meters roll out I suspect a lot of people are going to look for ways they can cut their monthly utility bills. Data is a powerful thing.

      • Steeple

        Very helpful; thanks. And agree that data and incentives are very powerful.

  • Steeple

    It is wonderful to see the competition amongst these various technologies. The worst thing we could to is to make the subsidies so great that we undercut the tremendous innovative work that is underway.

    • Bob_Wallace

      I doubt that it would be possible to over subsidize good things like renewable energy technology.

      Now what would be a bad thing is to be led astray by a concern troll….

      • Steeple

        Oversubsidize anything and watch how the creative juices drain away. That’s why economies like Singapore and Hong Kong have thrived (through innovation and the discipline of free markets) while resource rich countries like Saudi Arabia cannot develop a real economy.

        • Bob_Wallace

          You’ve achieved logic failure.

          There’s a difference between putting people on free money so that they have no reason to be innovative or work hard – Saudi Arabia…

          And creating very large rewards for being innovative and working hard which is what subsidies do if they are done correctly.

          • Steeple

            Markets create incentives, if incentives aren’t earned, discipline breaks down and we get bad outcomes. Replacing markets with subsidies is the same analog as taking the incentive away from someone in Saudi from earning a living due to their govt subsidy.

            No one subsidized the IPhone and thank heavens; look what innovation has been spawned by that.

          • mds

            Enough of your comments against subsidies for solar. All forms of energy have historically been subsidized to speed their adoption, to the benefit of industry and the economy. Persons, like yourself, that continuously harp on subsidies for solar, wind, and energy storage are hypocritical trolls with poor reasoning skills and an agenda.

            If you really believe subsidies are bad, then the larger amount of your tax dollars are going go for subsidies and similar tax benefits for fossil fuels and nuclear. If you believe subsidies are bad then you should speak out against these first and you should speak to your congressional and senatorial reps and ask them to stop these obscene benefits given to old and establish industries. This is nothing more than charity for the rich.

            The cost trends are very clear. There is NOT a good future for fossil fuels and nuclear power generation sources. Government investments in fossil fools and nuclear liability are not worthwhile. Their costs are not going to drop. We are exporting our extra fracked oil. The cost of gasoline at the pumps is NOT going down. Investments in solar, wind, and energy storage are already proving themselves beneficial. Their costs continue to drop.
            Steeple, you are a hypocrite and a troll. You are a member of the Flat Earth Society that does not acknowledge change because they cannot see it.

          • Steeple

            Subsidies are bad across the board and have created a Federal system of Crony Capitalism in areas like food, ethanol, alternative fuels, housing, etc… We need to get rid of all of these, as these spoils have been proven to be very corrupting to our political system. But instead, people like myself who call for reform of all of this get drowned out by others reaching for more govt support. And the Crony Capitalist system reinforces itself.

            By the way, I am a huge fan of solar and am very optimistic about its prospects. But I am a bigger fan of the discipline that free and properly regulated markets bring to us all.

          • Bob_Wallace

            Unless government had done the heavy lifting there would be no solar for you to admire.

            What corrupts our political system is our method of campaign financing.

            The “free market” is a myth. There has never been a 100% free market.

            If there was a free market within a few years a very, very small number of individuals would own everything. We would quickly move to one gigantic monopoly that would efficiently suck up everything of value and 99.99999% of us would be enslaved.

          • Steeple

            If the markets were unregulated, you might be right. Govt has its role; picking economic winners and losers should not be one of those.

          • Bob_Wallace

            There’s no way for the government to avoid picking winners and loser.

            When the government decides to purchase their #2s from Smith Pencils rather than Jones Pencils a winner/loser decision has been made.

            When the government decides that Professor Smith’s grant proposal is more deserving of support than Professor Jones’s a winner/loser decision has been made.

            What the government needs to do is to make winner/loser decisions based on merit rather than doing stuff like giving no-bid contracts to a corporation with which the Vice President has financial ties or building an expensive bridge which would see little use.

            And we need to realize that the government will not always get it right. None of us do. No individual. No private company.

          • Steeple

            The pencil makers are competing for business from the Federales just as they do from any other customer. Free markets at work; no subsidy. We should not have No Bid contracts, or build pork driven projects either. Those are not good uses of our resurces. Or pick winners and losers like the Feds did with Solyndra, Fisker, et al. Not only is it a waste, but it discourages true innovators who are disadvantaged by having to compete against subsidized competitors.

          • Bob_Wallace

            Here’s the choice.

            We either invest in ideas which could create American jobs or we don’t and we let other countries bring the new stuff to market.

            Now, if these new ideas were foolproof and had a short route to profitability then private money would invest. But some ideas just aren’t far enough along to be supported by private money.

            So, what’s your choice? Do we provide money to no ideas in order to avoid the very infrequent failures like Solyndra and Fisker or do we take a few chances in order to stay in the game?

            Are you interested in making the US a backwater country?

            Is that why you draw big, dark lines underneath the very few failures such as Solyndra and don’t acknowledge the very much larger number of successes?

            You know that if a liberal acted like that you’d be calling anti-American and a friend of China.

          • Steeple

            False choice. If that was the case, Google would not exist. America was built on innovation, hard work and rule of law. Government assisted, more in the rule of law category than anywhere else.

            Infrequent failures? MTBE and Methanol mandates? Old oil/new oil regulation? Other than the SPR, name a success in alternative government intervention in the energy markets.

            And enough of the insinuations that I wish ill on this country. Try taking the intellectual challenge like an adult instead.

          • Bob_Wallace

            The electric grid, certainly the rural electrification part of it.


            Hoover Dam.

            If you don’t wish ill to the country then why do you oppose our assisting new ideas from turning into successful businesses?

          • Steeple

            Those flood control projects were a good example of public investment, and they helped also achieve great benefits in power generation and electrification.

            But I guess I was hoping to hear a success post World War 2. Can’t think of one myself.

            Venture capitalists have the job of turning new ideas into successful businesses. It’s one of our greatest strengths as a country. Let’s leave it to those guys; they seem to know what they are doing.

          • Bob_Wallace

            Satellite technology, including GPS.

            Modern medicine.

            Jet airplane travel.

            Interstate highway system.

            (The Hoover Dam, TVA and rural electrification were not about flood control.)

          • Steeple

            Guess we’ll have to agree to disagree on what constitutes the proper role of Federal intervention. We would both agree on issues of infrastructure, public health, law and order; issues of the common good. Promoting one’s idea of the How vs the What is where we part ways.

            By the way, note that Flood Control was the driver.



          • Bob_Wallace

            I should have stated that Hoover and TVA were not solely for flood control.

            “The Tennessee Valley Authority (TVA) is a federally owned corporation in the United States created by congressional charter in May 1933 to provide navigation, flood control, electricity generation, fertilizer manufacturing, and economic development in the Tennessee Valley, a region particularly affected by the Great Depression.”


            Clearly power generation was a major part of Hoover as well.

            Bonneville Dam was constructed by the federal government for electrical power generation and river navigation.
            (How’s that new ID working out for you?)

          • Bob_Wallace

            Ah, I get it. You want America to be a second rate country.

            It’s clear now. Don’t assist new innovations. Let other countries have all the success. We can be a country full of, what, call centers and shirt sewers?

          • mds

            You said: “I am a huge fan of solar and am very optimistic about its prospects.” I’m calling bs. Your comments are always about cutting unfair subsidies for solar or renewables, never about cutting all energy subsidies starting with the largest offenders (big oil, coal, NG, and nuclear) to level the playing field and, as you claim, eliminate all subsidies.

            Prove me wrong. Respond with a few links to conservative drill-baby-drill sites where you are arguing to reduce subsidies and similar to benefits given to oil, coal, NG, and nuclear companies. Bet you can’t do that. Basically, in spite of your claim of being in favor of solar, you are not. You are a hypocrite, a troll, and a liar.

            …gee where else have I heard the sound bite term “Crony Capitalism” that you just used twice? I wonder why you use that term? Obama’s and Chu’s efforts to accelerate the adoption of solar and wind in the USA, and drive down the price, have been very successful. Germany was waaayyy more successful with FITs before that. Your view has already been PROVEN wrong. Go away.

          • Steeple

            Just to put you at ease, I will not call you a name or tell you to go away. There.

            I am a Libertarian when it comes to these issues; can you see my official party card that I’m holding up?

            Since I am in the hydrocarbons processing business (LPGs and Petrochemicals to be precise), I express my opinions about these subsidies more directly as I have that ability. You’ll have to take my word for that. My influence there is about as strong as it is here, given how entrenched all of this cronyism has become.

            Conservationist is about making the most of our resources. If we generate economically our power needs with renewables, that is awesome. We could then use our hydrocarbons for more valuable purposes and have then for longer.

          • Bob_Wallace

            Subsidies create incentives, if the market doesn’t provide adequate incentive to bring a new product/technology/service into production, then we can make up for the market’s inadequacy with subsidies.

            No one subsidized the iPhone, but tons of government money went into the technology that made the iPhone possible. The Steves would have never been able to produce their first Apple without the government first making the ‘computer on a chip’ a reality.

          • Steeple

            So markets are wrong, and need some “help”. From the smart people of course. Worked pretty well when FNMA subsidized the housing bubble. And so on. We need to get out of the way and let markets work. The incentive the have the best solar panel in the world to sell to Billions of people should be quite sufficient.

          • Bob_Wallace

            Gotta know when to hold ’em and when to fold ’em….

            There would be no nuclear industry without government subsides. Massive government subsidies.

            We wouldn’t be driving cars the way we do without the government paving our roads. Or flying much without government subsidies for planes and airports.

            Or using personal computers, cell phones, GPS, the internet, modern medicine, and on and on.

          • Steeple

            There is a difference between managing for the common good (clean air and water, infrastructure, national defense, law and order) and subsidizing specific markets, products and technologies. When governments get involved in attempting to manage the economics of markets, the outcome is rarely good for our general well being.

          • Bob_Wallace

            You don’t know that. The ‘outcome is rarely good’ is a right-wing myth.

            If we didn’t have government regulation of our financial markets our economy wouldn’t work. Look what happened when we listened to Reagan and lowered regulation of our financial institutions. We’ve still not recovered from that crash, five years later.

            Go live in a country with little regulation for a while. Let yourself be taken advantage of by the greediest and see how it works for you.

          • Steeple

            Necessary regulation of free markets is not the same animal as intervening via subsidy. You know that.

          • Bob_Wallace

            I certainly do know that.

            Regulations protect us against the greedy who are willing to hurt people for their own gain.

            Subsidies help bring new innovation to market and make our economy stronger.

            Have you ever considered how the US got to be such a dominate economy after World War II?

            Start with all the industrial capability we built with government money in order to build military equipment.

            Add in the generation of scientists, engineers and other useful people we created by subsidizing their education through the GI Bill.

            Subsidies are investments in the country’s future.

          • Steeple

            Comparing repaying those who risked their lives and limb to defend a country where our ships were being sunk within sight of land with Jeff Immelt scoring a subsidy for his wind turbine business is pretty strong equivocation.

            And it wasn’t the government’s $; it came from all of the people who forked up to buy War Bonds and make the sacrifices that helped us to defeat Evil and stay free.

          • Bob_Wallace

            I didn’t make a comparison. I sited examples of investing taxpayer money for public gain.

            To date our government’s investment in wind and solar have paid off handsomely. Wind-electricity has dropped from $0.38/kWh to $0.06/kWh. That’s more than a 6x drop in about 30 years. Solar panels have dropped from around $100/watt to just over $0.50/watt in the same time period. Almost a 200x drop.

            Bonds. How do those things work?

            Oh yes, the government passes a bond issue. They sell the bonds to individuals and other countries. And then later on they pay back those bonds with taxpayer money.

            Bonds are nothing but loan instruments.

            And War Bonds did not pay for the GI Bill. The Servicemen’s Readjustment Act of 1944 was paid by the budgets of the various agencies administering the separate parts.

          • Steeple

            What is the rate of return on these investments, Bob? I don’t know and I doubt anyone else does either. So how do we know if we have handsome returns? I guess we should just trust the Feds. That’s worked out really lately.

          • Bob_Wallace

            I don’t know if anyone has calculated ROI for our investments in electricity generation and energy in general. But we can look at what we’ve invested and get a feel for the results.

            Over the first 15 years of these various energy technology developments oil and gas got 5 times what renewables got (in 2010 dollars) and nuclear energy got 10 times as much. (Much of the renewable subsidies went to corn farms. A smaller percentage to wind and solar.)

            Between 1918 and 2009 oil and gas received average annual subsidies of $4.86 billion. (92 x $4.86 billion = $447 billion)

            Between 1947 and 1999 nuclear received average annual subsidies of $3.50 billion. (53 x $3.50 billion = $185.6 billion)

            Between 1980 and 2009 biofuel received average annual subsidies of $1.08 billion. (12 x $1.08 billion = $13 billion)

            Between 1994 and 2009 renewables received average annual subsidies of $0.37 billion.


            Renewables received 92% less per year than oil and gas, 89% less than nuclear and 76% less than biofuels. And for many fewer years.

            Those numbers do not include the cost of our three oil wars or the health damage caused by coal pollution. Many, many billions more that we’ve paid out.

            How have those subsidies paid off?

            In the last 30 or so years the cost of wind-electricity has dropped from $0.38/kWh to $0.06/kWh. A 7x drop. The price of solar panels has fallen from around $100/watt to just above $0.50/watt. Almost a 200x drop.

            As we all know the price of fossil fuels and new nuclear just keeps going up. (Aside from a short term drop in the price of natural gas.)

            So, looks to me that while we may not be able to cite a specific number the difference in payoff is rather spectacular.

            Wind and solar are the huge winners in our national investment portfolio.

            Fossil fuels and nuclear – losers. (Well, perhaps we lowered the pain we would have otherwise received. But they’re still losers.)

  • Breath on the Wind

    An interesting article that misses the point promised in the title. Something is only a “game changer” when compared to the existing game. Unfortunately the article doesn’t provide the baseline. Here is the LCOE of existing technologies:

    • Bob_Wallace

      I think it best to be cautions about accepting EIA cost projections, especially for solar. They continued to predict high PV solar prices when it was clear to all that panel prices were plummeting.

      Now (on the page you link) they predict a LCOE for PV solar of $130.4/MWh in 2018.

      Contracts are already being signed for PV solar at about $100/MWh (after subsidies are teased out).

      The UK recently installed utility scale solar for $1.59/watt. Install solar at that price in the parts of the US that get only 4.2 average solar hours and you get electricity for an LCOE of $90/MWh.

      Recently we saw a report about a new large array being installed in Spain for a projected $1.41/watt. That would drop the price close to $80/MWh.

      $1.41/watt in the Sunny Southwest and the price is about $70/MWh.

  • jburt56

    Wait, if this works what will happen to all the cranks that are always wringing their hands about the sun not shining? Will they have to commit seppuku?

    • mds

      No, not seppuku. They will realize the error of their ways. Many, who are highly “rationalized” humans will claim they were in favor of solar, wind, and energy storage all along. I predict Ruppert Murdock, WSJ, Washington Post, and Fox News will try to claim they invented solar.

      “Man is not a ration animal. He is a rationalizing animal.” Heinlein?
      Can anyone argue against a better, more economic, solution?

  • Quibbling over the KWH cost of CSP misses the point that this technology is carbon free and has no ongoing fuel expenses. Just the lack of “external costs” make CSP a winner in my mind. Factoring in the climate issue makes this mandatory regardless of the cost. Either we kill the use of carbon based fuels or they will kill us.

    • mds

      I like your view, but realize a large chunk of the USA doesn’t believe in AGW. The large fossil fuel companies will continue to perpetuate this unscientific view because “when money talks, bs walks”.
      However: solar, wind, and energy storage are already the lowest cost end-of-grid solution in some areas and in a few short years will be the lowest cost solution for almost all living in the Earth’s sun-belt, i.e. most of human population. Most humans have learned to take care of their wallets, i.e. they will be in favor of the best short term economic solution. Not if, but when solar, wind, and storage are cheaper than other alternatives, then they will simply stop being against them.
      This is THE winning strategy! How long will any argument against a lower cost solution last? Again, we are already there in some places. …and the cost of solar, wind, and energy storage continue to drop. The war is actually already won. It is now just a question of how long the battles will continue and which countries and companies will be the bigger winners in this new economy.

      • If we haven’t run out of time on the climate issue [and that’s a BIG effin IF] then you are correct to say that the war is already won. Fossil fuels will become depleted and what we now call alternative energy will, per force, be the way we power whatever might be left of the world (population).. If people don’t believe in AGW getting them to realize that human extinction will be the cost of the continued burning of FF’s is going to be a bit more difficult. Beliefs (I still believe in Santa and the Easter Bunny and Unicorns) that fly in the face of facts are almost as hard to change as beliefs when no facts support them. Oh well, in a short time, few will still have any ability to deny climate change, peak oil and what they mean to the economy, environment and our future,

        • Bob_Wallace

          Human extinction is over the top, IMO.

          I’m not going to quibble over the numbers, but somewhere from many thousands to several millions of us could continue to live even in a much hotter climate.

          Worst case, we move underground for the hottest parts of the year. Down where temperatures are a comfortable temperature year round.

          We put a lot of solar panels on the surface and grow our food under artificial light. We even install heat-blocking glass skylights and gain natural light.

          Here’s a subway dig. We know how to make big holes underground….

          • mds

            I don’t know if it is over-the-top. The asteroid strike at the KT boundary seems to have killed off every animal larger than about 50 lbs. The Permian extinction was an even greater event, with more than 90% of species being wiped out. Current evidence points to mankind as the greatest extinction event in geologic history.
            Remember that the Earth’s climate is a meta-stable system. There are these nasty positive feedback effects, like methane boiling up from ocean deposits and Alaska/Siberia tundra deposits, due to global warming (GW). The methane released causes even more rapid GW, and so on. We could see toxic changes in the atmospheric gas mixture along with large, long lasting, heat effects. “It’s not nice to mess with mother nature.” …just say’in

          • Bob,

            It’s not just heat that is the problem. With acidified oceans we can look for a big drop in O2 and later H2S rears it’s ugly head. Yes, we may be able to postpone the worst for a while living underground but as long term solution it looks iffy. At the least we are certainly talking about the end of industrialized civilization. (yes, I use the word civilization advisedly) Seems to me that getting serious about making the necessary changes NOW is a better option than banking on tunneling equipment.


          • Bob_Wallace

            Ed, the climate scientists whose opinions I’ve read do not consider runaway warming likely. These ‘end of the Earth’ predictions seem to come from outside science, from people who take a bit of information and spin it into a doomsday scenario.

            I agree that what we need to do is to cut our GHG emissions now. That’s why I volunteer on this site, to help spread the word of the technology we have that works.

            I don’t think we aid the process by overstating things.

          • Bob,
            The places that I get my information from are certainly not outside science. IPCC, IEA, Hadley etc. A doomsday possibility is something that most dismiss on emotional grounds. I struggle with it daily as I have grandchildren.

            Like you, I know that we have the technologies that will make a difference. What’s missing is the political resolve. The drag from the vested interests isn’t helping much either. Perhaps if people were a bit more concerned things would move faster. Sugar coating, so as to not seem “alarmist” could backfire.

            Runaway feedback loops are all but assured if we don’t get a handle on this soon. Already Methane is venting from the permafrost and clathrates. Fracking is also putting a lot of CH4 into the atmosphere. The climate is noticeably destabilized and with ice disappearing at an alarming rate I see ‘runaway’ as a real threat.

            The issue isn’t the “earth”…It will be here for a long time. The issue is what will the passenger manifest look like?

          • Bob_Wallace

            What do the IPCC, IEA, Hadley etc. specifically say about a doomsday possibility?

          • 4 deg C by mid century…

          • Bob_Wallace

            That’s not very informative…

  • jdavies

    This method of storing energy in molten salt, can it not be applied to other forms of generation, e.g. wind? Obviously it wouldn’t be as direct, but couldn’t wind energy be used to heat salt and then the rest of the process would be the same as seen here? Is the molten salt storage solution not a stand alone storage solution does it need to be coupled with solar thermal? Would using electricity (from wind) to heat the salt be too inefficient?

    • Breath on the Wind

      There are other ways to store wind generated electricity. Molten salts depend upon high heat which CSP has in abundance and wind energy does not. An Isothermic CAES system is ideal and additionally allows cheaper compressors installed in towers rather than turbines. Such a storage system recognizes that wind energy starts off as mechanical energy while CSP starts out as heat. An alternative would be using heat pumps to shift heat between two thermal storage tanks.

  • Others

    Solar Water Heating is a large source of energy and China has 80% of the World’s share. Its generation is much more than Solar PV, but is totally ignored.

    I wish the cost of CPV and Solar Thermal power goes down sooner. They Solar PV will power during the day while Solar Thermal will power during the night. It may cover 24 hours / day together.

  • Ivor O’Connor

    CSP is going to kill off fossil fuel electrical production within a generation. It will also pave the way for intermittent wind and PV to be produced in such high excess quantities we will start generating methane for the transportation industries.

    • Bob_Wallace

      Their best estimate is 10 cents per kWh by 2020.

      By 2020 we could see wind at 3 cents, solar at 5 cents, and storage under 5 cents.

      The jury is going to be out for a few years while we see how costs work themselves out.

      • Ivor O’Connor

        Storage under 5 cents? The only storage I see on the horizon are the heat storage tanks on CSP units. Batteries will probably be too expensive for decades other than for five or ten minute buffers. Compressed air in salt mines and hydro damns not so universally available. It all seems to point back to CSP. Until we are producing two to three hundred percent of what’s needed like some counties in Germany as an entire country.

        What am I missing for storage?

        • Bob_Wallace

          Pump-up hydro, used for daily cycling, is likely 5 cents or less. It’s really hard to nail down an actual price. A Swiss study claimed 3 cents with frequent cycling.

          Long term storage is more expensive, you’ve got capital tied up with no income stream for long periods of time.

          We’ve got 80,000 existing dams in the US. We could convert a small percentage of them to pump-up. Or we could build closed-loop.

          Ambri’s liquid metal batteries should be even cheaper. If they can be taken from working prototype to manufacturing.

          All I’m saying is that it’s a horse race. And the nags are just now entering the starting gate….

        • Shiggity

          If enough solar comes onto the grid the typical bell curve for electricity markets inverts. Electricity actually becomes most expensive when the sun isn’t shining. In the US, we spend the most money when the sun is shining (AC mostly).

          Almost all of the storage innovation is going to happen at the edge of the grid imo. It’ll be another core component of your house like your air conditioner, your heater, your hot water heater, etc. You’re also not going to need that much storage because energy efficiency is also going to start spiking soon, mainly due to LED lighting finally becoming affordable.

          The shift is going to be analogous to when we went from giant computer mainframes (large power plants) in the 70’s and 80’s to the PC in the 90’s (distributed generation / storage everywhere).

          SolarCity is already challenging XCEL the incumbant utility in Colorado.

          • Bob_Wallace

            It’s going to depend on which storage technology turns out to be the least expensive.

            Some technologies (pump-up, liquid metal batteries, CAES, isothermic, etc.) are not appropriate for single building installation.

          • Shiggity

            The grid is your primary storage asset. The battery on your end will be trimming the expensive peak load, you do not need a large battery for this, lithium-ion tech now is good enough.

          • Bob_Wallace

            It will come down to costs. Lithium-ion tech is good enough in places with high per kWh costs, not good enough in others.

          • sault

            And if you use the top 5% – 10% of electric vehicle batteries as energy storage and buffer (Vehicle-to-grid), then the capital costs for storage can be spread out over the transportation services the EV provides and the grid services its battery provides when it’s parked and plugged in. And as used EV batteries pile up, we can use them for an eye-opening amount of storage and other grid services for years after their automotive life is over.

        • mds


          Lookup and keep tabs on:

          Pellion – Lower cost Mg based battery

          Liquid Metal Battery Co. – Sadoway’s battery – There’s a good TED talk on this.

          24M – Stealth battery co.

          Envia – Lower cost Li battery

          “moving mountians” TED talk on approach to pump water approach that applies to almost any geographical area.

          LightSail – low cost buried tank compressed air storage. Lower cost for long term, large volume energy storage.

          Eos Energy Storage

          Aquion Energy

          Zinc-Iron Redox Flow Batteries

          Extreme Energy dry cells

          Compressed air at depth for off-shore wind turbines

          ZSW Li batteries


          That is not a complete list. I am not a professional in this field and there will be stealth companies we don’t know about yet.

          Bottom line here:
          The energy storage field is alive with numerous new developments, using a wide base of technologies. If any one of these is successful at the low costs begin targeted…

          Determining added cost per kWh for energy supplied from storage:

          ((Cost of storage per kWh) / Efficiency) / (number of cycles)

          Example of Aquion Energy:
          Target cost of $200/kWh
          85% efficiency (get 85% of energy stored back out)
          demonstrated 5,000 Deep Cycles (targeting 10,000)
          (($200) / (0.85) / (5,000) = %0.047/kWh
          = 5c/kWh cost added by this storage battery
 – April 2013
          Hope that helps, mike

          • mds

            Also, never forget that 1/3 of electricity use in the USA is for air conditioning. You can store solar power at very low cost as ice, cold water (sealed non-pressurized system), cold rocks, or other thermal mass. The only thing you then need to power at night is a fan to circulate air house-hold or business air across the cold mass.
            The need for air conditioning is greater when there is more sun, when solar is producing more power during the day. …SO we can supply around 1/3 of USA electricity using solar with absolutely no storage problems!
            This isn’t new. Ice based cold storage was used in theaters in the 1930s before air conditioning was advanced enough to handle that large a load. It is actually older than that. Old adobe builds in the USA south west and other old building in Africa and other areas were designed to preserve the night-time cold using thick rock or mud walls. Not much is cheaper than rocks and mud.
            Storage is not going to limit the expanded use of solar power, as many suppose. Not for a decade or so and by then many options will be available.

          • Bob_Wallace

            One company doing “cold storage” is Ice Bear. I took a look at their web site, hadn’t for a long time, and found some really interesting text…

            “The Ice Bear system is an intelligent distributed energy storage solution that works in conjunction with commercial direct-expansion (DX) air-conditioning systems, specifically the refrigerant-based, 4-20-ton packaged rooftop systems common to most small to mid-sized commercial buildings.

            The system stores energy at night, when electricity generation is cleaner, more efficient and less expensive, and delivers that energy during the peak of the day to provide cooling to the building.

            Daytime energy demand from air conditioning – typically
            40-50% of a building’s electricity use during peak daytime hours – can be reduced significantly. In kilowatts, each Ice Bear delivers an average reduction of 12 kW of source equivalent peak demand for a minimum of 6 hours daily, shifting 72 kW-hours of on-peak energy to off-peak hours.

            Ice Bear units are typically owned by utilities
            and installed at distributed locations behind the customer meter on commercial and industrial sites.

            When aggregated and deployed at scale, a typical utility deployment will shift the operation of thousands of commercial AC condensing units from on-peak periods to off-peak periods, reducing electric system demand, improving electric system load factor, reducing electric system costs, and improving overall electric system efficiency and power quality.”


          • Bob_Wallace

            Sadoway’s liquid metal battery company is called Ambri.

            Light Sail, I think, is aiming for “shipping container” CAES. They have a unique process for removing, storing, and reintroducing the heat created when compressing air. Heat loss is what make most CAES less efficient.

            Eos Systems zinc-air batteries are going to be installed on the New York grid in a few months. We should be able to see how well they perform. Eos is claiming $0.10/kWh storage – all costs included.

            Added some names to my Google Alerts. Thanks.

            Five cent storage and five cent wind would be a major game changer. New coal and new nuclear would clearly be dead. Even combined cycle natural gas would be in trouble. Wind and storage hedge against future gas price increases.

          • mds

            Bob, Thank you for the corrections. mike

          • Bob_Wallace

            Here’s another one…

            ” Hokkaido Electric Power Co. will invest in a 60,000 kWh vanadium redox flow battery from Sumitomo Electric Industries Ltd. to bolster its grid capacity amid rapid growth in power generation using renewable energy.”


            The extra storage will allow them to add more solar to their grid.

          • Ivor O’Connor

            Thanks Mike, it helps.

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