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Tech From Mars: Self-Cleaning Solar Panels

Taking a cue from technology initially created for missions to Mars, researchers have invented a self-cleaning system for solar panels that requires no water or mechanical movement, and uses only a tiny fraction of the electricity generated by the panel.

"A dust layer of one-seventh of an ounce per square yard decreases solar power conversion by 40 percent," said Malay Mazumder, PhD, of Boston University, in a press release. "In Arizona, dust is deposited each month at about 4 times that amount. Deposition rates are even higher in the Middle East, Australia, and India."

Compounding such difficulties is the worldwide goal of scaling up solar installations in rapid fashion to make meaningful contributions to power production. If huge projects like the Desertec plants in the Sahara and elsewhere are to become reality -- and an efficient, well-run reality, at that -- solutions to things like dust on panels are needed.

Mazumder's system, developed for NASA in use in Mars missions, involves use of an electrically sensitive material covering solar panels. When dust levels on the surface get too high, an electric charge flows over the panel capable of pushing the dust off the surface and back into the air. According to Mazumder, about 90 percent of the dust is removed within two minutes.

There are other self-cleaning systems out there, but they generally require water. Such systems might work well for home-based, small solar installations, but to keep the dust off vast arrays in remote desert locations, panels that clean themselves using bits of their own electricity and no water at all could make a huge difference.

$25 Billion European Smart Grid Market by 2020

A British consultancy predicts that between 133 and 145 million smart meters will be installed in European Union countries by the end of this decade, in keeping with the EU's aim to have 80 of households equipped with such meters by 2020. The market will be biggest in countries that have been relatively slow to implement smart metering, notably Germany, the UK and Poland, says Greenbang LTD in Europe's Smart Meter Outlook for 2020--a report that it's selling to interested customers for a cool 1800 pounds.

According to a precis of the report that appeared this month in Britain's Financial Times, the European country that got off to the fastest start on a large scale was Italy, which often surprises with its tech-savviness. With the assistance of California-based Echelon, 27 million smart meters were installed in Italy between 2000 and 2005. A program of similar scope is now underway in Spain, also involving Echelon.

On the face of it, Italy would appear to be the place to look, if you're trying to assess the near-term impact of smart metering on energy demand, conservation, and greenhouse gas emissions. Texas too: The report credits its smart metering with having helped avert problems in 2008, when lower than expected windiness idled its turbines.

Should We Just Pay Operators of Dirty Coal Plants to Shutter Them?

Last fall, inspired by the popularity and immediate success of the cash for clunkers program, I had the whimsical thought that maybe, instead of taxing coal-fired generators or forcing them to participate in a complicated cap-and trade system, we should should just pay them to shut down.

It turns out, as Grist blogger Ted Nace recently brought to my attention, that this little lightbulb had already lit up over other heads as well--several of them encasing bigger brains than mine. This is of more than merely personal interest because, with the death this year of the proposed U.S. cap-and-trade bill, if mandated carbon reduction is going to occur on a national scale, it's going to happen some other way.

Writing in the Wall Street Journal last August, T. Boone Pickens and Ted Turner suggested adopting a cash-for-clunkers program in the utility sector, so as to "save money and reduce emissions right away by retiring the oldest, least efficient and most polluting plants." Ten days later Silicon Valley entrepreneur and philanthropist Steve Kirsch proposed in the Huffington Post a "cash for coal" program, in which the government would pay owners of dirty coal plants their residual value, to finance the construction of clean coal plants.

Pickens, Turner, and Kirsch plainly meant the idea to be taken seriously and were not writing in mere whimsy. But the idea just as plainly was a trial balloon, and they did not linger over details. Kirsch confined himself to saying that any dirty coal plant would be eligible for replacement if replaced by a zero-carbon generator at an investment cost under $2,000 per kilowatt. Pickens and Turner preferred to see coal plants replaced by natural gas generators, which would cut per-kilowatt emissions roughly in half.

Nace, eyeing the added costs owners of dirty coal plants will incur in the next five years as they are required to install the latest in scrubbing equipment, has been calculating just how much they'd have to be paid to replace the plants instead. Going beyond that, he'd also like to show that net national savings would result from replacing all U.S. coal plants, which he believes will be necessary if the world is going to have any chance of attaining its 2030 greenhouse gas reduction goals. He believes the issue has legs: A site he helped build, "existing U.S. coal plants," has received 130,000 hits so far.

POSTSCRIPT (Sept. 2, 1010): Nace has now published his analysis explaining how he thinks the U.S. government could save money long-term by paying operators of dirty coal plants to close them. His basic concern is that although about one sixth of the aging coal fleet can be expected to be closed in reaction to rules requiring pollution scrubbers, we'll then be stuck with the other five-sixths, which will continue to emit huge quantities of carbon dioxide. Taking his cues from work done on the beneficial fiscal effects of tobacco regulation, Nace estimates how much money the government could save as a result of higher tax receipts from people who, instead of dying from exposure to coal emissions, continue to work.

His ballpark estimate of how much coal-emission mortality costs the government over a 30-year period? $175 billion. Additional costs attributable to morbidity over 30 years, the remaining time existing coals plants would be expected to operate, comes to $74 billion.

For Carbon Capture, DOE Moves Oxycombustion Ahead of IGCC

As reported by my fellow blogger David Levitan a couple of weeks ago, the U.S. Department of Energy has announced that its futuristic zero-carbon-generation project will be based on oxycombustion, not on integrated-gasification, combined-cycle technology,  as had been expected for more than a decade. With some reason, Levitan suspects the whole project may have turned into an ongoing boondoggle; certainly, FutureGen has come to seem rather like nuclear fusion--the technology that's always just a decade or two away but, like a mirage, never actually gets any closer.

Nevertheless, I'd like to offer another perspective: Possibly DOE's decision is sound and will open the way, at last, for FutureGen to actually be built and then lead, as hoped, to commercial prospects for zero-carbon coal-fired generation.

Several years ago, IEEE Spectrum magazine designated as one of its January winners the oxycombustion plant that Vattenfall, Sweden's national energy company, was building at Schwarze Pumpe, a site in eastern Germany. At that time, as we explained, IGCC still was generally considered the front runner in so-called clean coal technology. Yet the Florida plant that had pioneered the technology in the United States did not make a particularly prepossessing impression and for years had been generating the country's most expensive electricity by far. And now, two companies with substantial reputations in the power business, Vattenfall and Alstom, were betting on a different horse, dubbed oxyfuel or oxyfiring or oxycombustion.

In oxycombustion, coal is burned in an almost pure oxygen atmosphere, so that emissions contain virtually no NOx, which makes it easier to separate and store the carbon initially contained in the coal. IGCC involves gasifying coal, filtering out the carbon, and finally burning hydrogen to generate power. A big barrier to commercialization of oxyfuel is the initial separation of oxygen from air, which is expensive. But the technology is conceptually much simpler and arguably more elegant than IGCC.

Last November, Vattenfall announced that it was recovering virtually 100 percent of the carbon from the fuel burned at its small Schwarze Pumpe demonstration plant. Spectrum's account of the plant is somewhat dated, as the facility is being continually redesigned and rebuilt as part of Vattenfall's ongoing experiment. A fairly recent, nicely illustrated update about the oxyfuel plant is available.

Semiconductor Giant Pushes Millions Into Solar, LED Arena

One of the biggest semiconductor manufacturers in the world, Taiwan Semiconductor Manufacturing Company, is pushing its chips into the middle in another field: solar power and LED manufacturing.

Hsinchu-based TSMC announced that along with plans for new semiconductor foundries, they will spend more than $100 million on a LED manufacturing line and $218 million on a thin film photovoltaic construction facility. This comes a year after the company announced their intentions to move into these green tech fields, and follows on the heels of a number of business moves aimed at centering them in the push for solar and LED fields.

Late in 2009 TSMC acquired a 20 percent stake in Motech Industries, which is among the largest solar cell manufacturers in the world. More recently, the company reached a supply agreement with the solar thin-film manufacturer Stion, and in March they broke ground on an LED manufacturing facility.

Adding TSMC to the solar mix will only strengthen the tiny country's lofty position in the industry. Various reports from Taiwanese sources indicate that the country ranks third or fourth in the world in solar cell manufacturing, and adding TSMC's $3 billion in net income to that muscle can't hurt. And with nearby China recently overtaking the United States as the world's biggest energy user, the biggest market for those solar cells and LEDs isn't going anywhere.

(Image via Wikimedia Commons)

The Future is Now-ish: FutureGen 2.0 Gets $1 Billion For CO2 Capture

The Department of Energy announced an award of $1 billion in Recovery Act funding for what many have seen as the ultimate in energy-related government boondoggles, FutureGen. Only now they're calling it FutureGen 2.0.

The original idea of an ultramodern coal-fired electricity generating station with full carbon capture and sequestration technology was born in 2003 as part of President Bush's energy policy effort. Since then, projected cost overruns and controversies over siting of the project have plagued FutureGen, and environmentalists have decried it as a poor use of funds when investment in renewable energy could be quicker and more likely to produce results. The DOE pulled its funding in 2008, then joined back up with the FutureGen Alliance the next year, and has now clearly decided to push forward with a gigantic new infusion of funds.

This new version, though, is a far cry from the idea of a brand new near zero-emissions coal plant. Instead, an existing plant, Ameren's Unit 4 in Meredosia, Illinois, will be retrofitted with oxycombustion technology aimed at reducing emissions and allowing for capture of CO2. According to the DOE:

Oxy-combustion burns coal with a mixture of oxygen and CO2 instead of air to produce a concentrated CO2 stream for safe, permanent, storage. In addition, oxy-combustion technology creates a near-zero emissions plant by eliminating almost all of the mercury, SOx, NOx, and particulate pollutants from plant emissions. The Department of Energy’s National Energy Technology Laboratory studies have identified oxy-combustion as potentially the least cost approach to clean-up existing coal-fired facilities and capture CO2 for geologic storage.

Of course, if this is the "least cost approach," many might remain skeptical as to the practical potential of such schemes that allow the continued burning of our dirtiest fuel source. Spending $1 billion to retrofit a 200-megawatt plant won't exactly scale up to the size our coal-dependent country needs without some serious cost-saving advances in the near future. The FutureGen project, even its 2.0 form, does still claim to act mainly as a prototype for future projects, but more than seven years after the original idea came to light there has been shockingly little progress toward creating zero-emission coal plants. Maybe these billions would do better elsewhere?

(Image via Dori/Wikimedia Commons)

Wo die Atomare Wildschweine Wandern

Given a choice between nuclear power and being pure green, Germans much prefer greenliness to radiation risks. But given the choice between actually ingesting radioactive materials and having to give up their beloved boar sausage, evidently Germans would rather go nuclear.

Ultimately it's not such a funny story, despite the humorous spin sometimes put on it. Southern Germany, where the boar population has been soaring (for reasons that go beyond the scope of this post), happens to have been the part of the country most affected by Chernobyl fallout. It turns out that radioactive materials tend to concentrate in truffles and mushrooms, rather the way certain pollutants concentrate in shellfish. Unfortunately just those delicacies are what the Bavarian wild pig most loves, and when meat from the most proficient of the truffle sniffers ends up in Wurst, there's a problem for those who can't live without their boar sausage.

Last year, the German government paid hunters about a half million dollars to compensate them for boar meat deemed too radioactive to sell. But of course less radioactive sausage--wait a minute? wasn't somebody just saying there's no safe level of radioactivity?--is still ending up on dinner plates.

POSTSCRIPT, Aug. 6 (Hiroshima Day): The story is getting unfunnier all the time. Russian environmental officials warned yesterday that radiation also is concentrated in some of the forests that are getting consumed by the wildfires sweeping much of the country's western regions, as temperatures have soared to unheard-of highs. Some of that released radiation will be blown into Europe. It's always amusing to poke fun at Germans' love affair with the boar and their complex attitudes about greenliness, but really this is no laughing matter.

GE versus Coulomb in EV Charging

A previous post reporting the rollout of GE's WattStation network for electric and plug-in hybrid vehicle charging raised two questions concerning its competitive status versus Coulomb's ChargePoint network: GE's apparent claim that its stations will offer faster charging; and its general competitive position, given that Coulomb Technologies appears to have got the jump.

Regarding the first question, GE says it only meant that  Level 2 charging at 220 volts will be faster than Level 1 and 110, which is true of the Coulomb setup as well, as I understand it.

On the second point, GE managers say the following: "GE has been in the electrical distribution and protection business for over 100 years. As the GE WattStation is a vital part of tomorrow's electrical infrastructure, GE is able to leverage it's existing network of authorized distributors and electrical contractors to install the EV infrastructure - that includes circuit protection equipment, transformers as well as the GE WattStation - to provide a safe and reliable installed system. GE will also leverage our extensive experience in the utility transmission and distribution business to make sure that the GE WattStation is Smart Grid enabled for intelligent integration into today's power grid."

However the competition plays out for each of the companies, the existence of the competition can only be good for the development of a grid adequate to the needs of EV and hybrid drivers. Nissan having announced last year a home-charging program for buyers of its upcoming Leaf, infrastructure is not being neglected. That said, the ability of local distribution transformers to handle the added load from car chargers if plug-in hybrids really catch on remains much in doubt.

Siemens Completes Major Chinese Transmission Line

Siemens reports that it has brought into operation a high-voltage direct-current transmission line connecting the highly industrial Pearl River delta (Guangzhou, Shenzhen, and Hong Kong) with hydropower sources 1,500 kilometers to the west. With a transmission capacity of 5,000 MW, the HVDC line in effect obviates the need for up to 5 GW of fossil generation in the Pearl River delta, saving enormously on air pollutants and greenhouse gas emissions.

According to Siemens, power is being carried over the line at a record-setting 800 kilovolts, with losses of just 2 percent per 1000 kilometers and an additional 1.5 percent at the transmitting and receiving ends. The line is the second such electricity superhighway Siemens has installed in China to operate at 800 kV. Siemens developed a new "super transformer" for the lines, which it sees as "practically a blueprint for the DII (Desertec Industrial Initiative) desert power project."

Desertec could be a $500 billion project that would involve installing up to 470 GW of generating capacity in the Sahara, consisting of  concentrating solar plants, and transporting most of that power via HVDC lines to Europe. It may sound far-fetched, but if Europe it going to achieve it highly ambitious 2050 goals for renewable electricity generation and carbon emissions cuts, it may be the only way to go.

Tapping the Desert: Can Saharan Sun Really Help Power Europe?

Parts of Europe are already lapping the rest of the world in terms of renewable energy production and commitment, with Germany among the leaders in wind development and Spain holding a similar position in the solar power field. To meet the continent's lofty (relatively speaking) renewable goals, though, a mega-project situated south of the Mediterranean might end up as the most important piece.

The Desertec project, first conceived in 2003, has the following general goal: "Clean power from deserts for a world with 10 billion people." The flagship of that concept is a series of huge concentrating thermal plants in the Sahara Desert and elsewhere around North Africa and the Middle East, with transmission lines bringing the power north into Europe.

The numbers that Desertec can throw out are pretty staggering: by 2050, the projects are capable of generating up to 470,000 megawatts of electricity; only 0.02 percent of the land area in the region will be needed for all of the solar plants; in fact, only one percent of the entire world's desert area, if covered by solar power plants, could power, well, everything.

And now, in spite of an initial estimate that electricity might start flowing from the Sahara within 10 years, recent announcements indicate that number might be cut in half. The first pilot project appears slated for Morocco, and other countries in the region are on board as well.

Of course, any project so massive in scope carries with it a laundry list of pitfalls and potential problems. Transmission of all that electricity is probably exhibit A for such issues, but Desertec doesn't seem concerned. They note that the power loss over high-voltage direct-current transmission lines is about 4 to 5 percent per 1,000 kilometers of transmission; the costs associated with such losses, however, are made up by the remarkably high insolation (solar radiation energy) in the North Africa region, according to Desertec. And in fact, an industry group recently announced preliminary plans for an undersea grid of transmission cables in the Mediterranean to be developed in parallel with Desertec.

Among the other issues are cost - at least 400 billion Euros (about $520 billion) - and the risks associated with high level development in a number of politically unstable countries. But with Europe's 20-percent-by-2020 renewables goal only a decade away, such concerns seem to be taking a back seat. It looks more and more that before too long has passed, the Sahara really will help power Europe.

(Image via DESERTEC Foundation, www.desertec.org)

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