Mediterranean Solar Goes Large

By Kevin Bullis

Mediterranean Solar Goes Large

Two sprawling solar power plants are complete. One produces electricity at night.

At the new Gemasolar solar plant in Seville, Spain, 2,650 large mirrors concentrate sunlight to generate 19.9 megawatts of electricity. It was completed and started up in May.

Credit: Torresol

351 Days Ago
06/10/2011

really cool

Are the plant power outputs rated at peak power output or with an average power output?

The plant in southern france yields a mega watt every 4.9 acres.

Wonder what the cost per kwh is?

348 Days Ago
06/13/2011

*"Wonder what the cost per kwh is?"*

We don't know yet until maintenence over several years is quantified. Trying to find those numbers from past similar projects (like in the Mojave dessert, Ca, USA) so far has turned up nothing. I wonder why that is?

348 Days Ago
06/13/2011

For O&M data you should check with the Calif Energy Commission and the Calif Public Utilities Commission. The cost per kWh depends on the capital cost, the financing structure (including interest rates, depreciation, tax structures, incentives, etc.), and the O&M costs. In capital-intensive energy projects with little or no fuel costs, energy costs are dominated by the annualized capital costs plus O&M. The levelized busbar energy cost BBEC formulas for specific utilities have all of those considerations built into the calculations.

345 Days Ago
06/16/2011

Is there a way to hook up a generator that runs on freon or something to reuse some of the lost heat and make it more efficient?

Optional - run the waste heat lines underground and store the heat for use in Greenhouses and such during the winter months.

351 Days Ago
06/10/2011

subhead

The subheadline "One produces electricity at night." is an empty promise.

351 Days Ago
06/10/2011

Did you read the caption to the other pictures? The system stores energy in molten salt, which can continue to produce electricity after the sun goes down.

348 Days Ago
06/13/2011

You are right: I didn't (and still haven't) read the captions. Please point me to a more in-depth source than TR.

Amazing what a thread this has resulted in.

342 Days Ago
06/19/2011

What an odd thing to say... Do you think they made that whole thing up or what? What is it that keeps you from reading the caption?

351 Days Ago
06/10/2011

How is the subheadline an empty promise if the plant is ACTUALLY GENERATING ELECTRICITY AT NIGHT? Do you always ignore pieces of reality that don't conform to your pre-conceived notions and beliefs about the world? This is the same reason why people who deny the mountain of scientific evidence that humanity is messing up the climate are called DENIERS.

351 Days Ago
06/10/2011

I'm pretty sure that one group of people call another group "deniers" for the same reason that the second group calls the first group "alarmists": because they don't agree and have resorted to name-calling. None of which changes the fact that this plant can store some heat to produce some electricity after it gets dark.

351 Days Ago
06/10/2011

I call it denial when someone dismisses observed facts and solid scientific evidence because it doesn't fit in with the way they see the world. He dismisses the fact that this plant can generate power at night because that fact doesn't fit in with his belief that solar power isn't a dependable energy source. Climate Change deniers do the same thing with the mountain of observed evidence that we have and the sound theory derived from that evidence that concludes we are jacking up the Earth's climate. A head in the sand is still a head in the sand regardless of why its owner put it in there in the first place.

The term "alarmist" is thrown around not because there is a sound scientific case in support of their accusation, but because the talking heads on Faux News, talk radio or the public relations specialists at the fossil fuel companies say so. One side has the science while the other side has the marketing muscle to spread its misinformation.

350 Days Ago
06/11/2011

There is every bit as much scientific evidence against the climate change theory as there is for it. None of the predictions are actual fact, it is all computer modelling. Therefore only a theory. The PR marketing machine on the believers side has more marketing muscle than the scientists who claim it is all nonsense. The broke and insolvent governments of the world see it as a solution to their insolvency so any way of generating a new tax prentending it to be necessary to "Save the World" love it and support the believers and squash the evidence against it. Won't even give it air time in mant cases as for as I can see.

The greenie cult coming out of the current school system are utterly brainwashed from within the system which denies anything outside of it so can't tell a fact from a theory.

If you care to do an impartial search you can find as much actual scientific evidence against climate change as there is for it. As an armchair expert I think you are very courageous taking either side with asserted rightness just yet.

349 Days Ago
06/12/2011

The alarmist are putting their money where their mouth is and are investing in land that is not going to be so hard hit by global warming today and use alternative energy (to oil).

It looks like France and Spain Alarmist will have a lot of US immigrants once the oil runs out.

If the US, on other hand, puts science at the forefront and forget about PR campaigns and marketing, that would allow the country to adapt to the coming change. This country after all has the engineers, the scientist, and (even today) the money.

Lets recognize the deniers are just lobbyist for the oil industry trying to squeeze the last dollars out of Americans even if that means sinking the country. Most of the world is no longer taking the bait and are investing in alternative energy.

America has some alternative energy projects, but could do even more if more constituents asked for it.

349 Days Ago
06/12/2011

What does oil have to do with it?

None of our electricity comes from oil.

349 Days Ago
06/12/2011

"There is every bit as much scientific evidence against the climate change theory as there is for it."

That's a bunch of boloney:

http://www.skepticalscience.com/global-warming-scientific-consensus-intermediate.htm

"None of the predictions are actual fact, it is all computer modelling. Therefore only a theory."

Plate Tectonics, Evolution and the Germ Theory of Disease are "only" theories as well. Would you turn your back on those as well?

"The PR marketing machine on the believers side has more marketing muscle than the scientists who claim it is all nonsense."

The fossil fuel companies have WAY more marketing muscle than the climate scientists. Just LOOK at all the ads they can purchase, talking up the tar sands or how awesome oil drilling is. Notice how these ads are just coming back after their absence due to the BP Deepwater Horizon disaster? Also, do you EVER see ANY ads purchased by climate scientists warning people of the dangers of climate change? I guess they don't have to because people can just look at the news and see the droughts, wildfires, floods and heatwaves for themselves.

"The greenie cult coming out of the current school system are utterly brainwashed from within the system which denies anything outside of it so can't tell a fact from a theory."

Wow.... this is an informed statement... and look at all the facts presented to back it up too...

"If you care to do an impartial search you can find as much actual scientific evidence against climate change as there is for it. As an armchair expert I think you are very courageous taking either side with asserted rightness just yet."

If you ignore all the intentional misinformation paid for by the dirty energy companies and their stoolie "Think Tanks", you will find that virtually NO ONE that actually knows anything about climate doubts that humans are causing climate disruption now and in the future. I'm still waiting for JUST ONE legitimate scientific paper showing that the consensus on man-made global warming is wrong. Here's a short read citing over 60 papers that you should read:

http://www.skepticalscience.com/docs/guide_to_skepticism.pdf

348 Days Ago
06/13/2011

That is simply not true. The so-called evidence against global warming is a distortion of the science, or a very myopic examination of one part of the puzzle, or an exaggeration of inevitable inaccuracies in scientific data, and the oil companies have billions more to spend on their propaganda than all of the honest scientists and poor governments do. It is a contest between right versus might.

348 Days Ago
06/13/2011

The article in Science magazine titled "Evidence for Large Decadal Variability in the Tropical Mean Radiative Energy Budget" Has some good evidence against global warming.

Something to do with how they observed large amounts of energy per square metre from the sun over some tropical area, far higher than what's needed for global warming, and the average temperature didn't increase over the observation period.

As well as cloud cover being a major factor in how much energy was coming from the sun, which global warming alarmists say doesn't happen apparently.

I was led to the article by a TED talk by Kary Mullis, a Nobel prize winner and all round smart and funny guy.

Anyway, on to fusion power, go go ITER!

Then it's only a small step to pocket fusion, kapow!

348 Days Ago
06/13/2011

That canard is debunked here:

http://www.skepticalscience.com/lindzen-choi-2009-low-climate-sensitivity.htm

There, that was easy! All right deniers, take you (next best) shot!

346 Days Ago
06/15/2011

Someone here is a man after my own heart! The dirty truth is:

There is tons of miss-information going around. This Substantiates my theory that those of Money and Power supply this miss-information to support and protect their fortunes. Big Oil being one, Financial Institutes being one, Government being one, and Big Business being one. What is the truth? They lead us into thinking the way they want. They build reality. Shame on them!

My plea is that folks that know the truth don't let the temptation of money and power shut them up, from revealing the truth. I'm a Boy Scout that tries very heard to live by the Scout Law and Oath (Look it up). To bad our county doesn't have much leadership with high moral values! I guess if parents don't instill morals in their kids, and the schools don't either, you get what we have, immoral behavior on a mass scale. Lying and cheating justified!

Please do the right thing, tell the truth the whole truth, nothing but the truth, so help us whom-ever, or what ever you believe in.

Best Regards,

345 Days Ago
06/16/2011

@Archie: "There is every bit as much scientific evidence against the climate change theory as there is for it. None of the predictions are actual fact, it is all computer modelling. Therefore only a theory."

Please could you explain what you mean by "climate change theory" and then provide some scientific support for this statement. There is overwhelming evidence that human activity is increasing the carbon dioxide levels in both the atmosphere and the oceans and that this is in turn raising average temperatures across the globe.

The following data shows the increase in CO2 and demonstrates that it is from human sources:

http://www.esrl.noaa.gov/gmd/ccgg/carbontracker/

http://climate.nasa.gov/evidence/

http://www.esrl.noaa.gov/gmd/ccgg/trends/

The following data (which is probably what you object to) demonstrates the correlation between CO2 in the atmosphere and average temperatures.

http://www.ncdc.noaa.gov/paleo/globalwarming/temperature-change.html

http://www.skepticalscience.com/co2-temperature-correlation.htm

Even the "skeptical" website c3 headlines includes a chart showing warming following CO2 increase.

http://c3headlines.typepad.com/.a/6a010536b58035970c0147e1e05a26970b-pi

So it seems fairly well accepted that there is some level of anthropogenic warming. The key question that follows is what is the significance and what should we do about it. By all means disagree with what we should do about it, but it is fairly well accepted that this is happening at some level.

Finally, you talk about a theory as though it is something unreliable. In a similar way it is a theory that the sun will rise tomorrow or that mountains are caused by tectonic plate movements, but you probably don't have problems with making decisions based on those.

http://www.teachthemscience.org/scientifictheory

Computer modeling is only as good as the underlying model, so criticising computer modeling is meaningless. I can use computer modeling to predict that flipping coins will result in 50% heads and 50% tails, but the important thing is the model behind it.

345 Days Ago
06/16/2011

@kbillet

The dirty truth is that you don't know who to trust, so you would rather believe the people who say that you should do nothing. No-one likes being told what to do. Not totally unreasonable, and quite in line with normal human assessment of risk, but could be devastating for future generations if you get it wrong.

330 Days Ago
07/01/2011

Thank you for defending logic and honest scientific methods. I have actually seen an article in "Scientific American" where they stated that different oceans could rise at different rates! I guess they have overpowered gravity with hyperbole. They did not print my comment.

I will believe in global warming being a problem when I see the high tides getting higher on the beach in a noticeable manner. That would still not prove that man had much, if anything, to do with it. The deserts of the world were all once underwater.

351 Days Ago
06/10/2011

How is this large?

These two plants are each under 20MW. By standards of normal power plant output, this would be quite small. A small natural gas generation plant might put out 300MW, while a single nuclear reactor is generally around 1GW. The Three Gorges Dam complex in China will have a total output of 22GW.

.

It's nice to see solar making some headway, but I think we all need to understand how much land area it's going to take for solar to make a significant dent in a nation's total energy needs. A few 100 acre installations at 20MW are not going to do it. 100 acres does not seem that much to me. This would be the size of a small family farm. We need to start looking at solar the same way we look at agriculture, to which we as a matter of course devote gargantuan amounts of land. We have become used to the aesthetics of a farm or dairy or ranch and accept that as a necessity taking up enormous swathes of our surroundings. Certainly more needs to be done aesthetically with solar equipment to make it blend in as much as possible with the environment, but there also needs to be some adjustment to the public perception of what utilitarian beauty is.

351 Days Ago
06/10/2011

I see this more as a proof of concept than a finalized implementation. It uses mirrors to generate electricity in reasonably large quantities. One thought that I have looking at this structure is that in some ways it is not fully utilizing the space available. I imagine that future structures will have mirrors in three dimensions that are on a mobile platform that uses programmatic logic to array the mirrors in the most efficient pattern possible as the earth rotates. If one collection tower can not sufficiently generate electricity at higher watts, perhaps several towers can be put at the center, with an array of mirrors focusing on each tower.

Conversely, perhaps in 20 years or so we will have similar structures as this, but floating in space. Perhaps they can collect the energy into fuel cells and then transport them to earth on biodegradable sky sleds (manufactured in space from asteroids perhaps) that glide onto the ocean surface for pickup by ship. Or some similar system of transport from space, such as, perhaps parachuting the fuel cells down. Either way the idea is the same – collect solar energy in space where the mirror arrays can be very large, and non-interruptible, and transport the energy to earth in fuel cells. This would alleviate the negative possibilities of a microwave beam transmission which I’ve read proposed (one dreads to consider what would happen if someone pointed that into a city), and could make for clean renewable energy in large enough quantities to make the process worth the initial costs. For one thing the sun is not about to run out of energy any time soon. Also, if the arrays were positioned near the moon then solar storms could be avoided perhaps by maneuvering the entire array into the moons shadow until the solar wind passes.

I see some distinct advantages to the Solar Energy model, and I like to think that these efforts are first steps in a long but fruitful process.

351 Days Ago
06/10/2011

That is an excellent point, and one that I think most people don't really think about. The amount of land needed, on top of the costs, are huge.

Let's take the power plant that stores heat for overnight power generation, pictured above. It's stated capacity is 20 MW, and its owners expect it to produce 110 GWh per year (a little optimistic, but we'll give it to them). It cost 260 million pounds ($420 million) to build, and its expected ongoing costs haven't been disclosed as far as I can tell. And it sits on 185 hectares (460 acres) of land.

Now let's pretend that our goal is to say, convert the US's current nuclear and non-renewable electricity consumption completely to solar power within 20 years by building a lot of plants just like this one. And to have all new electrical production come from plants like this one. What would it take?

Supply: The US currently generates about 3.9 PWh (Petawatt hours) per year. That is increasing about 1.5% annually. So in 20 years we will need to generate about 5.25 PWh. We currently produce about 0.4 PWh per year of that from non-nuclear renewable sources. So if all those renewable plants keep running, within 20 years we need to construct 4.85 PWh of annual capacity from these solar plants.

Number of Plants: As this plant is expected to produce 110 GWh annually (0.00011 PWh annually), we shall need 44,090 of these plants to accomplish our goal. That's the 4.85 PWh target to replace current plants and build for future needs divided by the 0.00011 PWh of production for each plant.

Cost of Initial Construction: If we manage to construct them at today's prices, and even bring the price per plant down by 25% due to the massive associated economies of scale, and avoiding any issues that might result from supply or equipment shortages resulting from such a massive project, the cost of the whole project would be $420 million * 0.75% * 44,090 facilities: $13,888,350,000,000 That's about the current size of the entire US debt, or the entire current annual economic output of the entire US. And that doesn't even factor in the transmission infrastructure that will be needed since these plants will all need to be in the desert southwest in order to produce at anywhere near their capacity. It basically comes out to $43,000 for every man, woman, and child in this country. Or roughly $172,000 for a family of 4.

Land Requirements: This plant sits on 185 hectares, or 460 acres of land. If we need to build 44,090 of them, that means we'd need roughly 20,281,400 acres of land. That's approximately 31,690 square miles. To make it easy to picture, that's like covering every square land inch of the states of Rhode Island, Delaware, Connecticut, Hawaii, New Jersey, and Massachusetts in power plants just like this one. But hey, we probably don't need those 6 states for people or plants or animals after all, right?

Do I hate solar? No! But do I think people underestimate the problems or the immense amount of infrastructure? Yes! That's all I was hoping to shed light on with this post.

351 Days Ago
06/10/2011

Nobody said that this one approach would solve all our energy problems. Those energy problems are caused PRECISELY because we put all our eggs in too few energy baskets. We aren't diversified enough is what I'm saying. Solar PV is getting so cheap so fast that by 2015, it will be cheaper than coal power, so it would be a boneheaded idea NOT to put it on every roof of the country. Wind power just needs more certainty in grid access and, since it's already the cheapest power source in many regions of the country, it is poised to expand rapidly as well. Ocean wave and Geothermal power are becoming practical and provide a conventional base-load capability while offshore wind has huge potential. Add in biomass, waste heat recovery, efficiency, conservation and a growing acceptance that we live on a finite planet and can't keep expanding our consumption indefinitely and you get a realistic scenario of almost completely clean energy by around 2050.

On a side note your $13T price tag would be compensated somewhat by the lower healthcare costs and property damage we would enjoy from a cleaner environment as well as no oil / resource wars and avoiding the devastating impacts of climate change.

351 Days Ago
06/10/2011

Hopefully we can revisit some of the assumptions about solar power:

US electric demand: No it is not growing, at least not in the last several years. US demand peaked in 2007 at 4.157 PWh; 2010 generation was 4.12 PWh. 2011 is also on track to be substantially less than 2007. This trend can not be hung on economic lulls either, as productivity per kwh purchased continues to rise. [1]

Land Use: While Seville's Gemasolar does indeed use a couple hundred hectares for a 20MW plant, it is not reasonable to assume the same energy density when scaling up a one-of-a-kind plant four orders of magnitude, which in effect assumes that Gemasolar packed its mirrors as tightly as possible, or that its utility buildings, transmission, and access roads must be replicated for every 20MW. I find it more useful to recognize that 200W(peak)/M^2 is commonly obtainable from high volume commercial photovoltaic panels, yielding an energy density at 100% space utilization of 560MW(peak)/square mile, and then derating that figure for whatever space overhead figure you choose. To generate the US's 4.2 PWh/year, using the typical low solar capacity factor of 16% (four peak equivalent hours per day) that gives us ~5200 square miles (not 31,100), or a space 70mi x 70 mi.

Now, lets derate to 10,000 sq mi, or 100 mi x 100 mi and then look at land use comparisons. We'll see that the 'solar will cover all of Rhode Island', or this, or that claim is a red herring:

o US public road system - 1% of US land area or the size of South Carolina

o One military base, White Sands Missile Range -3200 sq mi.

o All US building rooftop area residential and commercial - 6600 sq mi

o US total corn harvested area ~143,000 sq mi, about 40% of which (60,000 sq mi) is used to produce ethanol. Note that solar PV or thermal does not need to displace _any_ arable land [2]

The US uses vast tracks of land for many things, but somehow comparisons only become terrifying when the subject of solar power arises among Robert Bryce and other 'I play an engineer on TV' pundits. Solar has some problems, namely energy storage, but I hope this land use silliness stops soon.

Cost: Solar is still expensive upfront, but consider: the US's 4.2 PWh requires the equivalent of 2 billion tons of coal _every year_ (2000 kwh/ton), and for low sulfur coal at $50/ton that's $100 billion per year, after year, after year. Double that (at least) for a natural gas equivalent. That cost is only going up, while the price of solar is only going down.

[1] Table 1.1 http://www.eia.gov/cneaf/electricity/epm/chap1.pdf

[2] http://farmlandforecast.colvin-co.com/2011/03/30/rising-corn-acreage-failing-to-meet-us-feed-ethanol-use.aspx

351 Days Ago
06/10/2011

That's a fairly rosy picture of the solar power situation. We will need more power in the future. As resources become scarce, more energy will be needed to create or to extract and recycle existing resources.

For $1 trillion dollars we can build at least 250 large, modern and safe nuclear power plants. This is the amount of money we pay for oil every 1.5 years. We can burn most of the existing atomic waste sitting around. This is economically the most sensible course. It is much cheaper and the technology already exists. Exploiting the thorium cycle, the fuel supply is enormous.

We just had the worst possible type of reactor accident in Japan. Despite all the radiation fears, no one has yet died. Also, the accident was caused by an extraordinary natural disaster that is a risk only in certain parts of the world. The plants that failed were designed in the 60's. Much safer designs now exist that don't require active cooling.

Sure solar power plants are clean (not counting the coal burned to build them). But I just don't think it's practical in the near future.

Let's get over the nuclear paranoia. We harnessed fire which is in some ways even more dangerous. Whole cities have burned, but we have to learned to control it and live with it.

350 Days Ago
06/11/2011

"But I just don't think it's practical in the near future."

But Thorium reactors and US based fuel reprocessing are ready in the 'near future'? With 8-10 years required to approve and build an existing PWR, I hardly think so. I agree it should not take so long, or cost so much in the US, but it is what is.

349 Days Ago
06/12/2011

Good idea. I feel the same way. I think the nuclear question is a little more complex than most realize but ultimately, unless we hold off until fusion, it is the best answer. Unlimited energy for a really long time and minimal pollution. I think solar and wind and other ideas are really cool and I hope they find their niche but I just don't think they could ever power the world. I want a world where everyone can consume all they desire without any problem and nuclear make that possible.

349 Days Ago
06/12/2011

Yup.

Yet nuclear abstinence and fossil burning special interests have blocked these designs, perversely in the name of safety as we are now stuck with old designs that are inherently unstable for purposes of producing plutonium.

But now there is no market for plutonium, so the remaining 98% of uranium and the plutonium is placed into cooling tanks as "waste".

And we were left to build hundreds of coal burning plants that are far more damaging and deadly.

http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html

And when these obviously dangerous reactors are shown to be dangerous, and those who blocked their replacement say "See, they are dangerous!" Thanks for nothing.

349 Days Ago
06/12/2011

This is the best cost/land analisis of all the posts.

345 Days Ago
06/16/2011

Your casually and irresponsibly overlooking some valuable real estate and resources. There's no good reason why every new home and building in the Southwest U.S. shouldn't have solar panels as part of the building requirements.

343 Days Ago
06/18/2011

The thread is loaded with detailed analysis of land use.

Here's one reason for not _requiring_ every home to have PV on the roof: cost. It's still $25k-$35k for a 5KW residential system. You want to mandate it, you pay for it.

341 Days Ago
06/20/2011

Is that all

Really! Is that all. Sign me up. Seriously. I would easily accept that cost mortgaged over 30 years.

337 Days Ago
06/24/2011

I meant that if residential PV was mandated by law as suggested above, you pay for mine too.

351 Days Ago
06/10/2011

ArtInvent: "The Three Gorges Dam complex in China will have a total output of 22GW..."

Sure, at the cost of uprooting 1.3 million people, or twice the population of the US's Washington, DC. And BTW, the Three Gorges sits on a seismic fault.

ArtInvent:"...It's nice to see solar making some headway, but I think we all need to understand how much land area it's going to take for solar to make a significant dent in a nation's total energy needs. A few 100 acre installations at 20MW are not going to do it. "

A land area of 100 miles by 100 miles of solar photovoltaic _will_ do it (~500MW per square mile) producing 5-6X the entire US electrical load at peak power. The problem of storing that power isn't solved yet, the land use is not a problem in the US.

348 Days Ago
06/13/2011

PV solar systems are not restricted to land; they can also be erected on floating isles within coastal range and serve multi-purposes. E. g. producing hydrogen from salt water. The hydrogen can be harvested from installed storage tanks.

346 Days Ago
06/15/2011

Many of these installations are going up in deserts, or marginal land.

In Tennessee, I've passed by a tiny installation on a half acre cut out of the pine forest. It is next to a highway and what looks like a municipal building.

Pine trees in that area are reclaiming land too low quality for farmland. You pass through a dozen miles of scrub forest between each tiny town.

Even a 500 acre installation in that area would be swallowed up by the surrounding forest. As it is, some poor soul is tasked with mowing down the pine seedlings regularly to keep them from overgrowing the solar panels.

351 Days Ago
06/10/2011

it's awsome !

It can be open for tourist as its artically beautiful

342 Days Ago
06/19/2011

You're going to have to visit it in a chopper. On ground level it won't look like anything special.

350 Days Ago
06/11/2011

Is it supposed to be a sunflower packing? Because that's awesome.

350 Days Ago
06/11/2011

It's never good enough for some people

For those seeking easy answers, renewables are never good enough, despite the fact that they are always getting better. Of course, one can always find criticisms of any system, and what's often missed is the fact that fossil and fissile systems often have far more problems than are commonly acknowledged as well. I think that events in Fukushima have demonstrated yet again that the so-called easy answer of nuclear is the true empty promise here, not solar. We simply cannot trust an industry like nuclear which consistently downplays risks, shaves costs, and still swears on a stack of bibles that nothing could possibly happen....until it does happen. I have often said that if a solar power plant made everything in a 50 mile radius toxic and uninhabitable for 100 years then some of the critics might have a legitimate argument against solar that would be at least as strong as the real argument that does exist against many aging, slipshod nuclear facilities. The same goes for wind. We see a few fake tears about a minuscule number of birds that might be killed, but wind power cannot possibly produce the catastrophic results of nuclear.

One of the reasons that I don't like calling these sources "alternative" is because there really isn't an alternative. In the not too distant future we will have to rely upon technologies like this, as fossil fuels become more rare and expensive. Nuclear is already obscenely expensive, so that's been less of an issue. In theory, nuclear could be made cheaper, and many new designs exist, but you notice that new gee-whiz nuclear plant designs are not the ones that people want to build. It seems that wind and solar have a better track record of fielding innovations nuclear does, despite it's massive and unwarranted superiority complex.

350 Days Ago
06/11/2011

solar power

I hope thar soon solar panels will become available and feasible for roofs with some 100-150 sq.m area.

As there are millions and millions such roofs, this would make a real impact on renewable energy' without gobbling up huge chunks of land.

348 Days Ago
06/13/2011

Commercial PV installations for roof-top application are established products. Very large installations are appearing on commercial buildings, with 1.9 MWpeak of PV on the Google campus in northern California. A Google search will turn up many commercial suppliers of such systems.

350 Days Ago
06/11/2011

Now Needs Design

As matter of fact, solar panels on the ground are 'technologically' cool, but for the people living there and tourists visiting there design needs to be considered. And I wonder the efficiency of current solar panel.

349 Days Ago
06/12/2011

Beautiful

I don't know what the neighbors are complaining about in France. If I had a wind mill, a solar panel farm or a concentrated solar plant near my house, I would organize pick-nicks at the foot of the plant :-) They are all engineering marvels.

349 Days Ago
06/12/2011

I didn't see any mention of water requirements. Unless the unit is air cooled these would not be feasible for the American Southwest.

The 3000 pound elephant in the room with all these renewable projects is the need for fossil fuel backup for night time and windless days. The best dent I have seen to date would be 30% fuel replacement leaving 70% fossil fuel consumption. Maybe we can get it to 50% but It is completely unknowable if we can get past that mark. It would take an out of the blue solution to do so. Better have nuclear as a backup if you believe in global warming (as I do…)

Also for of: critics of costs. The only cheap solution is fossil. Renewable and nuclear will both be expensive.

Perhaps I am the only one who thinks this way, but I think we should just tax the heck out of carbon and be done with it. Let the market build low carbon solutions and get the politicians out of the way**

** Politicians are historically good at the taxing part but notoriously poor at thinking. Could you imagine how inept our computers would be if politicians engineered microprocessor development via subsidies? We would still be using 8” floppy drives.

349 Days Ago
06/12/2011

jj256: "I didn't see any mention of water requirements. Unless the unit is air cooled these would not be feasible for the American Southwest...."

Well photovoltaics don't require any water or arable land and are perfectly suitable for the US Southwest. Also note that the largest nuclear plant in the US, Palo Verde outside Phoenix, uses a colossal amount of water.

349 Days Ago
06/12/2011

I wasn’t talking about photovoltaics - I was discussing the plant featured in the article.

All Rankine cycle power plants require a steam condenser be it a power tower as described in the article, nuclear or the steam section of a natural gas combined cycle (Brayton/Rakine) plant.

They can be either air cooled (less efficient) or water cooled (more thermally efficient).

If a solar power tower is water cooled then it pretty much has the identical water requirements of a “colossal” nuclear plant on a per megawatt basis.

That said, your point is none the less valid. Photovoltaics require no cooling. They are very useful in reducing fossil fuels but are still limited due to storage.

My concern is not getting to the 50% fossil fuel reduction. We know how to do that. I am very concerned that well intentioned but missguided policies will paint us in a corner when we need to conquer the remaining 50%.

348 Days Ago
06/13/2011

jj: Yes, I agree with you, and trust that nuclear (new and better) fills a substantial part of hole not eventually filled by solar and wind.

My own personal preference is to backup solar/wind with natural gas powered electric plants as

1) upfront construction costs for gas plants are by far the least expensive (~$1/Watt); the drawback previously with gas has been operating costs,

2) gas electric can be spun up/down nearly instantaneously,

3) the grid already uses gas-electric for this purpose, with more gas-electric capacity in the US now than coal - it simply sits idle a much of the time,

4) with solar/wind taking half the load natural gas reserves should extend well into the next century at low cost.

349 Days Ago
06/12/2011

Works for residential

I own a house just a fraction over 2k square feet and has 400A electrical service. That square footage figure can also have a four car detached garage added to it and also a greenhouse - that depending on weather factors can contribute in exchanging air to the house.

This house works quite fine to generate power to the house at full load and under any weather conditions - indefinately; and also sells power back to the grid. The same system can be made to work in any state outside of Alaska.

More in relation to the article. I'm well aware of the specs and stats for such large scale power systems. On a smaller scale it certainly helps, but unfortunately will never be practical on a larger scale, yet... The united states does have the ability to phase out fossil fuel if it wanted to

349 Days Ago
06/12/2011

How are you producing your power? Is it all photovoltaics?

348 Days Ago
06/13/2011

Photovoltaic (PV) "arrays" (both fixed and tracking) are a good part of the system - yet are entirely the part that sells back to the utility. Let me explain further...

My system is both active and passive. A portion is "pumped through" and eventually stored as hot water. Other parts are technically stores in rather massive wall structures. And even some in marine (salt water) fish tanks. There's even a detached small greenhouse that is ducted to the house.

By my calculations (and if worked properly) a greenhouse of less that one third of the volume of a house can heat almost any house.

Since I am still connected to the grid I still do run from their system strictly for routine maintanance twice a year - otherwise I'm selling back to the utility. Technically this could qualify as a net metering program.

Two more items... If I had to do it all over again I would be PV only; and could run a profit well within ten years. I'll be officially publishing all of this by the end of this year

348 Days Ago
06/13/2011

Reality

Add in the capacity factor and you know why Spain is in trouble.

348 Days Ago
06/13/2011

Add in the fact that the plant can generate power well into the evening, matching the demand load profile rather well and you'll see that you made a misinformed comment.

348 Days Ago
06/13/2011

solar thermal central receiver power

Over 30 years ago I wrote about the possibilities for large-scale renewable energy power generation. Today the reality eclipses by far what we then thought was a bold view of the future. Still, we got it largely right. My paper "The Helios Strategy" published in 1978 is available on line for free.

www.iiasa.ac.at/Admin/PUB/Documents/WP-78-008.pdf

327 Days Ago
07/04/2011

Google earth shows lots of available ocean realestate

I never understand the climate deniers. It's really about them wanting to hold onto their oil and coal-fired energy sources. But what's so bad about using solar and wind? They work, and they're free. My guess is that in an earlier age, these same people were railing against the use of masts with cloth sheets hung on them for pushing boats along. Why mess with perfectly good oars pulled by strong men?

304 Days Ago
07/27/2011

Spectacular Site of Solar Power

It is indeed a great feat of Solar Power.

Dr.a.Jagadeesh Nellore(AP),India

Wind Energy Expert

E-mail: anumakonda.jagadeesh@gmail.com