Other solar thermal designs, like solar towers, are also gaining traction. This is where sun-tracking mirrors, called heliostats, focus light on a central tower. "Troughs are a tried and true technology, but you also have these new central receiver plants that achieve higher temperatures and, in theory, lower costs," said Mark Mehos the CSP program manager at NREL.
The Ivanpah Solar Electric Generating Station near the California-Nevada border is one such design. The 377-megawatt plant will use 170,000 heliostats and power 140,000 homes. When it comes online in October, it will double solar thermal production capacity in the United States. The project received a $1.6 billion loan guarantee from DOE.
Spain, Italy and Saudi Arabia gearing up
Compared to photovoltaic plants, CSP generators require sunshine that is more reliable, so they are limited geographically to sun-soaked locales. Photovoltaic panels are also modular, so developers can construct plants faster. However, mirrors are more durable than panels and do not degrade over time. As these plants get larger, power variability becomes a greater concern with photovoltaics but not with CSP.
On the back end, solar thermal plants have more in common with coal- and gas-fired generators than with photovoltaic farms. Thermal plants, both renewable and fossil-fueled, generally use the Rankine Cycle to produce electricity. This is where a heat source heats steam in a closed loop that spins a turbine to generate electricity. The steam then condenses and recirculates.
However, solar thermal systems, because of their high temperatures, could also use a power block driven by supercritical carbon dioxide, according to Gleckman. These turbines use a Brayton Cycle, which is similar to how jet engines work, except the turbines use a hot liquid -- in this case, carbon dioxide -- instead of air. This power block would use 30 times less space than Rankine turbines, substantially cutting materials and maintenance costs.
"If you could use a different way of producing the electricity that is less expensive, then you have a potentially disruptive approach," Gleckman said. "It's very challenging to come to cost parity [with fossil fuels] without doing things on the power block cycle."
Despite their steady performance, Mehos said, solar thermal plants would likely serve on the grid to absorb demand surges rather than provide baseload power. "In today's market, my belief is, really, there is no market for baseload CSP systems. The value of that energy in non-peak or shoulder times is low," he said. Part of the reason is that grid operators do not generally price energy storage, but CSP developers are trying to change that.
Many other countries are also developing CSP plants. Spain leads the way, with more than three dozen running or under construction.
"The two biggest markets are expected to be India and Saudi Arabia," said Gleckman, pointing out that Saudi Arabia wants to move away from burning oil for electricity so it can sell the oil instead, while India wants low-carbon energy to power its development.
Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500
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21 Comments
Add CommentAlmost like the chicken and the egg thing. Please let me explain. Solar thermal has advantages. It stores heat which can later [at night] be converted into electricity. Solar PV has advantages because it is simple. You sit it in the sun and it creates electricity.
Reply | Report Abuse | Link to thisTo infer that one form of solar is more important or better than the other, is not very realistic when we view our total energy picture. I would never consider setting up a solar thermal array in my backyard to create electrical power even if I could. Who is going to watch the feed-water system and monitor steam turbine speeds for example. Of course everything could be automated but my local building code department might have a few well founded questions they would like to ask me, LOL. By the same token, setting up 12-32 solar panels on my roof can create enough energy to significantly reduce my electric bill and most of the time is just sits there quietly doing its job.
Each form of solar energy has its advantages and disadvantages but they are BOTH needed when we consider our overall energy picture. Energy consumption in America looks much like our old friend the "normal distribution curve". A little in the morning, increasing at noon, peaking in late afternoon and dropping off in the evening hours. Solar of BOTH types have advantages and disadvantages during these time periods.
The biggest single advantage of any type of solar power is that it is clean power. You don't have to believe in solar power to appreciate clean air and water. As an individual homeowner or small business owner, YOU can invest in and become your own energy company. That is an important freedom we still have in America.
End of Story
sort of like using a magnifying glass to smoke a water pipe. its called solar hits. Look it up.
Reply | Report Abuse | Link to thisMany solar thermal plants switched to solar PV because the rapidly dropping price of solar panels totally changed the math on these projects. The storage ability of these plants is useful, but will it be cheaper and easier to manage than just leasing a little bit of capacity from thousands of plugged-in electric vehicle batteries? Where are we on the learning curves for solar PV and thermal, and what are the expected to look like over the next few years? Can solar pv and thermal work together? (PV shaves midday demand, allowing solar thermal plants to build up heat for the afternoon and evening hours.)
Reply | Report Abuse | Link to thisI don't know the answers to these questions, but it is an interesting time to be looking into these things!
The Potassium Chloride or Potassium Fluoride salts must be manufactured extremely pure (5 sigma or more), and this purity must be maintained at all times of operation. The salts will have a tendency to valence break and take to solute the metals ions of the containers and pipes in which they are moved about to steam generators and heat exchangers. In essence the salts will take pipe metal to the Gamma State, suspend ions of the working metal in its matrix, and then deposit those metals epitaxially onto the surface of a valve or fitting and effectively 'weld' the valve in place. This will happen within hours unless a specific amperage DC voltage is applied across the fluid from multiple anodes and ample time be given to extract the extraneous ions onto a sacrificial cathode. This will be enormously expensive and greatly slow the ability to turn the BTU content/salt volume to the turnover level required to generate 1200 or 2400 lb steam in a classic steam turbine application.
Reply | Report Abuse | Link to thisHaving designed, budgeted, constructed and destroyed several of these systems, and watched them catastrophically and epitaxially fail, and finally only partially solved it, and seeing that this is a fledgling technology, the solar heat salt, or for that matter nuclear heat salts, are a bit of a way off. These challenges have yet to be solved for a large scale operation, and the cost is sadly more than one might think. I wish it were a bit cleaner, because the heat storage potential is enormous, yes. 8-) - TES
Oh and supposedly Mythbusters debunked the myth of Archimedes setting the fleet of Roman Ship afire in the Second Punic War. What Mythbusters fell short on, was they were not experienced sailors. They knew nothing about their flammable target. They tried to set a block of fresh cut wood on fire with the polished reflector lens. Of course that would not work. A ship is not a fresh cut block of wood. That is not what Archimedes did. The topside deck of an ancient warship, was ground tackle stowed with pitch, tar, aeromatics, oakum, flax fiber and oilcloth, soaked into a salt dessicated and ashen splintering wood structure that had actually been at sea for some time. Just such a seagoing combination is an extreme fire hazard. In the hot sun these vital topside maintenance items would burst into flame in no time due to the increased kindled surface area of the oakum and flax fiber, intermixed with deckwide and locker stored release of pitch/tar aeromatics, ethers, and alcohols.
Reply | Report Abuse | Link to thisHaving sailed for 30 years and having been on a burning ship at sea and in the Damage Control team of firefighters, I have no compunction accepting that what Archimedes claimed was indeed very possible.
I had a factory constructing parabolic trough tracking collectors back in the late '70s & early 1980s. We used to laugh at Sandias efforts. For a start, Fresnel lenses are not nearly as efficient as first surface anodised aluminium sheet mirrors. Also per square metre of collecting area they were a fraction of the cost. In manufacture the parabolic shape was simple to form. You only had to push the two sides of the sheet towards each other & it naturally formed a parabolic shape. You kept bringing the sides in until you had the required focal length then riveted it into a light frame. The focal length was only a few inches from the bottom of the sheet & was focused onto a gravity heat pipe. Over the top a curved sheet of 5mm clear acrylic was fastened. This prevented heat loss but also kept the mirror surface clean. Also this approximating a wing & created a low pressure area above the acrylic in a breeze & gave a self cleaning surface. Any breeze lifted the dust off the surface. We ran steam & sterling engines, under root soil heating in greenhouses & that sort of thing.
Reply | Report Abuse | Link to thisTrying to store heat at elevated temperatures I doubt will ever be viable. In fact I came to the conclusion that thermal solar only had really good applications for water heating up to boiling point. Above that temperature you have the added expense of pressurising the water or moving to a more expensive medium. Water can store more heat per lb than any other medium up to boiling point & is easy to contain & insulate. There were a couple of other interesting things we developed. In particular absorption cycle refrigeration. With my knowledge in the field, I could have cashed in during recent years with all the hype. I have refused to do so. I will not be a party to robbing taxpayers by making unsustainable promises. I have seen nothing in the intervening years that has surpassed the things I did all those years ago as far as energy produced per dollar is concerned. One day I will put all our research, tests, photos & video up for all to see but not untill the hype has passed. Otherwise I would be contributing to it. Also links to publications during that era that lauded my work. I have already divulged too much. I do not wish to be found.
Hey, you're being anti-capitalist by not cashing in! Since dirty fossil fuels get a huge advantage by getting to spew their waste into the environment FOR FREE, the paltry help for clean energy from the government is more just a feeble attempt to right a lot of the market failures in the energy industry more so than any kind of "hype"!
Reply | Report Abuse | Link to thisAnd talk about unsustainable promises! Coal, oil and natural gas companies act like we can keep using their product ad infinitum without any consequences! All fossil fuels will eventually run out and burnign them all is changing the Earth's atmospheric chemistry to boot!
Wow, so all that hype about thorium power is a bit off the mark...
Reply | Report Abuse | Link to thisAn interesting experiment. The PV crowd has always got away with not having to pay the 17 cents a kwh gas backup cost from fast spooling low efficiency gas backup run inefficiently and always covered by the taxpayer. If the solar thermal backup can extend for several hours then much more efficient gas CCGT gas backup can be used, actually saving GHG's unlike PV. Still many times more costly than nuke power, causing the destruction of desert water and ecology resources, with 8 cent a kwh 5 times sized transmission lines to drag the power to market, makes this just another dangerous distraction in the AGW battle.
Reply | Report Abuse | Link to thisThe carbon fuels actually work 24/7. The alternatives will NEVER do that. While ever consumers demand reliable power, fossil fuels will be used even if it were to be supplied by government owned utilities, as is the case in many parts of the world, including some states in Australia. The only exceptions are where nuclear power or a guaranteed supply of hydro is available. Your disparaging free enterprise is disgusting. How many people have you employed over the last 50 years? It is something I am very proud of that you will never experience. Providing the employment & stability that has allowed families to prosper, buying nice homes & educating their children? I doubt you even employ yourself. Depend on a government funded position no doubt.
Reply | Report Abuse | Link to thisWell this will be my last posting on this article, time to move on. YEARS ago I was probably one of the biggest renewable energy supporters on this planet and I guess I still am but it is not the only thing that is important. As would have it, renewable energy systems are making significant strides in cost reduction and thankfully they have because:
Reply | Report Abuse | Link to this1. Both Oil and Natural Gas will sooner or later run out or become to expensive for the average individual to use.
2. Nuclear of all types that I am aware of: PWR, BWR, Breeders, Traveling Wave, Molten Salt, High Temperature Gas Reactors - all the same. There are people who believe they will save the planet and those who fear an accident. After working in the nuclear power industry for 20+ years and another 10 in closely related industries, I have significant DOUBTS nuclear by ITSELF will save the day - however it will be a contributor.
What will save the day is an all-of-the-above-strategy. Wind, Solar, Bio-fuels, nuclear, some oil, some coal, some natural gas, some conservation, some energy efficiency and LESS WASTEFUL energy consumption.
We waste vast amounts of energy in America. A typical power plant like a coal, natural gas or nuclear unit is only about 30-35% efficient. Oh sure Combined Cycle plants are more efficient but how many of those are we building and they STILL BURN something carbon to produce power. We are wasting 70% of all the heat energy we create REGARDLESS of what type of fuel is used to create that heat.
We use 5 passenger cars to run to the grocery store or corner market for a gallon of milk. We use 1/2 and 3/4 pickup trucks carrying one person and nothing in the bed of the truck to go 25 miles to work. We still heat homes with oil fired or natural gas fired furnaces that are less than 92% efficient. Not only that things like heat pumps or Combined Heat and Power [CHP] units are still mostly foreign words to most consumers. Don't believe me, go ask your neighbor which is more efficient, a heat pump or a 92% condensing gas furnace. And if you are reading this and don't know the answer, shame on you because individuals like us need to be helping our neighbors understand. We need to become helpful; not argue about which source of energy is best.
I am not a climatic scientist but rather an engineer by profession and realize one thing. If we continue on this path of promoting only our favorite source of power, then we will surly fail.
The Chinese are kicking your ass on nukes my friend.
Reply | Report Abuse | Link to thisConstruction started on their 2017 in service HTGR at 2 cents a kwh promising to drop to half that with factory production and 70% devoted to synfuel production. That amongst at least 2 other sure thing R&D streams, the Fast Sodium using Russian tech, and the LFTR using American.
Obama spends bupkis with his nonukes administration devoted to Big Oil's worthless carbon capture, wind and solar projects.
Wind/solar are unworkable as a zero carbon solution with storage costs driving them to the 2 buck a kwh level several hundred times the cost of nuclear. Every dime spent is wasted.
You efficiency spew is nonsense as we have an entire world that can't wait to start using energy like we do. Only nuclear can do that and still give us a liveable planet.
Get with the environmental program and off Big Oil's bandwagon and try to help mankind into the future instead of hindering it.
Dear sethdayal:
Reply | Report Abuse | Link to thisLast time I read one of your posts was about 2 years ago. It, like the above, said almost the same thing. China this, China that, Obama spends, big oil, carbon capture, renewable energy is useless and etc.
I would imagine many bloggers are getting a little tired of the same old thing over and over again. So here is a suggestion I sincerely hope you at least consider. It is NOT meant to be condescending or argumentative since in my opinion, that almost never accomplishes anything.
Please show us your energy plan or if you don't have a plan, allow US to help you develop a plan. There are many of us with expertise in energy that might be willing to help. Right now most of the nuclear technology in our country seems to be wrapped in companies like Westinghouse, GE, Mitsubishi and others.
In my opinion, Congress doesn't have a clue how to develop and energy plan since most member of Congress are attorneys and aside from all the attorney jokes they do have a purpose I guess. In addition, the United States Nuclear Regulatory Commission [USNRC] seems to have no urgency in its task of expediting or approving new designs. We need a strategy that lights a fire under their behinds, LOL. Here are just a few ideas that I think should be at least considered or included in an energy plan. This IS NOT an all inclusive list by any means.
1. Social engineering techniques to dispel public fear.
2. Incentives to cities or states to create a desire to site new plants.
3. Number of new jobs to be created and impact on hosting states or society.
4. Recommend technology[s] out of all of the different designs you mentioned.
5. Recommended retraining programs for displaced workers, and of course;
6. Study of financial impacts on the oil and gas industries which currently run Congress. Without their buy-in we are just wasting data bits and server kilowatts.
It doesn't make any difference what YOU want or what I want. What matters is that we come together and present a strategy that systematically; over time; solves PROBLEMS. You know - clear cut goals and objectives that will be supported by the people, business and the industries affected.
Thank you for considering my recommendation.
"...What will save the day is an all-of-the-above-strategy. Wind, Solar, Bio-fuels, nuclear, some oil, some coal, some natural gas, some conservation, some energy efficiency and LESS WASTEFUL energy consumption..."
Reply | Report Abuse | Link to thisThese type of statements are common and sound very wonderful. And most person's gut reaction is yep, that's what we need to do. And at one time I was a true believer in that strategy. Unlike most people though, I have a certain appeal for calculation, and when I applied numerical methods to the above strategy, no matter what I did, the conclusion was inescapable - NO, that WILL NOT work, not a chance, not a hope. The problem is just too large, and the available capital & resources too small to make that work.
The inevitable conclusion is THERE IS NO CHANCE of solving the emissions, global warming, peak oil, high energy cost, reliance on precarious imported energy supplies CRISIS, with an ALL-OF-THE-ABOVE approach.
We need to focus capital on the most cost effective methods, or we have no hope whatsoever of success.
You need to take a real hard look at numbers:
1) The per capita energy consumption, for a family of four that amounts to 380 MW/yr in the USA or a continuous avg power consumption of 44 kw, in Canada it is 60 kw.
2) The EROEI. Newer energy sources require higher energy inputs. This will try to increase 1) even if conservation and efficiency improves, The Net Energy Cliff:
upload.wikimedia.org/wikipedia/en/9/9b/Net_energy_cliff.gif
3) The growing demand for energy in the Developing World. Some here in the West, in particular Greenies, like to pretend that the Developing World with its burgeoning population is going to be content to live in abject poverty and won't want to industrialize. A false dream, non-OECD energy consumption:
iea.org/stats/pdf_graphs/24TPES.pdf
4)The Carbon Abatement Cost, this is using rational methods of getting the most cost effective = THE ONLY EFFECTIVE solutions, here is a rational analysis for Australia:
bravenewclimate.files.wordpress.com/2011/11/co2-abatement-cost-with-electricity-generation-options-in-australia.pdf
Wind & Solar will not work and are a total waste of money. They have odd niche applications which are so unimportant in the overall plan that they can be ignored.
5) The #1 Green Energy country on Earth, and the wealthiest, see what they did with a religious all-out effort on Solar & Wind:
iea.org/stats/pdf_graphs/DETPES.pdf
6) See what France did in the same amount of time with a basic Nuclear Expansion:
iea.org/stats/pdf_graphs/FRTPES.pdf
SA editors please check. There's something wrong with the article. $35.80 per megawatt? Is that the cost to put up a power plant? Ridiculously cheap. Or do you mean megawatt-hour?
Reply | Report Abuse | Link to thisSolar thermal operating on Brayton cycle? That's for gas turbine engines. You need fuel and combustion. What's the fuel? If it's powered by a fuel, how the heck can that be solar thermal?
O.K. so I read all of your referenced materials. What do you suggest?
Reply | Report Abuse | Link to thiskW, MW TW all frequently used in industry. I believe many people just assume [love that word] a unit of time is involved.
Reply | Report Abuse | Link to thisWell Tom not that it is much of a plan but its hard to disagree with your motherhood statements except for getting Big Oil on the program - like that's a gonna happen.
Reply | Report Abuse | Link to thisThe first step that you missed is some sort of Global warming generated massive killer of American voters, a coupla of thousand dead would be a good start. The irate and terrified voter would then start hangin corrupt politicians, media and Big Oil exec's from street lamp poles when they find out the degree that corruption has interfered with the simple nuclear solution where the investment needed pays back at 40% per annum.
Have you ever seen a power plant that costs $35.80 per MW? I will buy it. They don't know what they're talking about.
Reply | Report Abuse | Link to thissethdayal said in part: "The first step that you missed is some sort of Global warming generated massive killer of American voters, a couple of thousand dead would be a good start.
Reply | Report Abuse | Link to thisTom G. responds.
I would have a tough time considering a plan that contains some type of wish to kill off a couple of thousand people. We have enough death and destruction already on this planet and to date, they have been proven to be very poor population control methods. While certainly some form of "action plan" is needed, I prefer a less violent approach.
You did mention that getting oil companies to respond in a positive way will be difficult. Here is one company that is making progress and has some oil company investors.
http://www.coolplanetbiofuels.com/
Also wondering if you follow this site?
http://www.resilience.org/stories/2013-01-17/nuclear-jan-17
Maybe it has a ROI of 150 years, LOL.
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