Energy and Global Warming News for April 9: Solar-powered desalination; Black silicon makes solar cells cheaper; GE to boost research in China
"Energy and Global Warming News for April 9: Solar-powered desalination; Black silicon makes solar cells cheaper; GE to boost research in China"
Saudi Arabia meets much of its drinking water needs by removing salt and other minerals from seawater. Now the country plans to use one of its most abundant resources to counter its fresh-water shortage: sunshine. Saudi Arabia’s national research agency, King Abdulaziz City for Science and Technology (KACST), is building what will be the world’s largest solar-powered desalination plant in the city of Al-Khafji.
The plant will use a new kind of concentrated solar photovoltaic (PV) technology and new water-filtration technology, which KACST developed with IBM. When completed at the end of 2012, the plant will produce 30,000 cubic meters of desalinated water per day to meet the needs of 100,000 people.
Photo caption: “Heat transfer: IBM’s concentrated photovoltaic system can focus 2,300 times the power of the sun onto a one-square-centimeter solar cell without causing heat damage, thanks to an indium-gallium liquid-metal alloy that conducts heat away from the cell.” Credit: IBM
KACST’s main goal is to reduce the cost of desalinating water. Half of the operating cost of a desalination plant currently comes from energy use, and most current plants run on fossil fuels. Depending on the price of fuel, producing a cubic meter now takes between 40 and 90 cents.
Reducing cost isn’t the only reason that people have dreamed of coupling renewable energy with desalination for decades, says Lisa Henthorne, a director at the International Desalination Association. “Anything we can do to lower this cost over time or reduce the greenhouse gas emissions associated with that power is a good thing,” Henthorne says. “This is truly a demonstration in order to work out the bugs, to see if the technologies can work well together.”
While the new concentrated PV technology might generate affordable electricity, solar power still costs more than fossil fuels in many parts of the world. But even with those high costs, using it to power desalination makes sense, Henthorne says. “You’re not doing it because it’s the cheaper thing to do right now, but it would be the cheapest thing down the road.”
A simple chemical treatment could replace expensive antireflective solar cell coatings, bringing down the cost of crystalline silicon panels. The treatment, a one-step dip in a chemical bath, creates a highly antireflective layer of black silicon on the surface of silicon wafers, and it would cost just pennies per watt, say researchers at the National Renewable Energy Laboratory (NREL). They’ve used it to create black silicon solar cells that match the efficiency of conventional silicon cells on the market.
The crystalline silicon wafers used to make today’s solar cells are treated to create a textured surface, then coated with an antireflective layer, usually silicon nitride, using high-vacuum processes. This additional layer increases the value of a solar cell by improving its efficiency–it suppress reflection so that more photons actually enter the silicon wafer instead of bouncing off its surface, increasing the flow of electricity off the cell. But the extra layer also adds to the expense. “We believe it can be cheaper,” says Howard Branz, principal scientist in silicon materials and devices at NREL. Even with a coating, the best-quality silicon solar cells typically reflect 3 percent of the light that hits them. Branz’s lab is developing inexpensive ways to create black silicon, which reflects almost no light.
Prototype solar cells made at NREL have the best efficiency ever reported for black silicon cells. Monocrystalline silicon cells with the black surface, and no additional antireflective coating, convert 16.8 percent of the light that hits them into electricity, about the same efficiency offered by a typical crystalline silicon solar cell coated with antireflective material. The previous record for black silicon cells was 13.9 percent.
To replace the vacuum-deposition processes used to treat the surface of a silicon wafer, Branz’s lab developed a chemical process that can be performed at ambient temperature and pressure using equipment already on site at solar-panel factories. A wafer is submerged in a bath containing a water solution of hydrogen peroxide, hydrofluoric acid, and chloroauric acid, which is made up of hydrogen, chlorine, and gold. The small amount of gold in the acid bath acts as a catalyst for chemical reactions. It’s not clear exactly what the chemical reactions are, but they lead to the formation of gold nanoparticles that drill nanoholes at varying depths into the wafer. Branz says the gold can be reused again and again.
GE is starting to let its research and development organizations in China take the lead on research projects, rather than just playing a supporting role to its global research headquarters in New York, says Xiangli Chen, the general manager of GE’s China Technology Center.
The 10-year-old center in Shanghai is one of GE’s four global research centers and home to 1,300 researchers and engineers. An additional 700 researchers develop health-care-related projects in the country at two other locations. In the past, GE has focused on creating products in and for rich countries such as the United States, and these products were sometimes adapted for poorer countries. Now it’s developing products in research facilities in China and selling them in China before finding new applications for these products in its more traditional markets. GE says this is essential for competing in China, where many companies are able to offer low-priced goods and create new products for emerging markets such as China and India, as well as richer countries.
The increased competition for GE from local companies in China is due in part to a massive push by the Chinese government to promote clean energy and R&D. In recent years, it has rolled out a range of renewable energy targets and financial incentives, including significant tax breaks for companies that invest in research related to energy.
A Silicon Valley company said on Wednesday that it had raised $10 million to bring to market a novel way of making thin-film solar cells.
Applied Quantum Technology is one of a score of start-ups trying to develop low-cost solar cells made from copper indium gallium (di)selenide, a compound that can be printed or deposited on glass or flexible materials.
That has proved a tough challenge and start-ups like MiaSol©, Nanosolar and Solyndra have raised hundreds of millions of dollars to perfect the technology by building propriety solar cell-making machines.
But Michael Bartholomeusz, Applied Quantum Technology’s chief executive, claims that by using off-the-shelf machinery from the computer hard drive industry, his company has been able to dramatically cut its capital costs.
“Companies have become equipment manufacturers first and product manufacturers second,” said Mr. Bartholomeusz. “Building a manufacturing platform around a nascent process, then trying to marry a nascent process with an unproven manufacturing process is a daunting task.”
“This is an extremely capital inefficient and a long process,” he added. “We come from the hard disk drive and optical storage industry, which are the ultimate commodity industries today.”
Hard drives are manufactured using a process called sputtering that deposits materials in layers on a disk. Mr. Bartholomeusz said his company had developed a process that used “dry sputtering” to make an entire solar cell.
The wind-energy industry last year installed 5,700 new turbines with more than 10,000 megawatts of generating capacity “” enough to serve more than 2.4 million homes “” said the American Wind Energy Association.
Texas leads the nation with more than 9,000 megawatts of wind generation capacity, including 2,292 megawatts added last year. But Iowa is the leader in relying on wind-generated electricity. Last year, 14.2 percent of the state’s electrical power came from wind “” compared to 1.8 percent nationwide.
Indiana added 905 megawatts of capacity in 2009, second only to Texas. Measured by total installed capacity, the top states are Texas, Iowa, California, Washington and Oregon.
The data from AWEA reveals another year of continued growth for wind power. But industry leaders said they are constrained by the nation’s aging electrical transmission system and that sustained growth depends on the continuation of expiring federal tax credits as well as a new national requirement that power companies must get a portion of their electricity from renewable sources.
“What we have to do is get these policies in place that really provide that long-term commitment, so we can have that exponential growth,” said Denise Bode, AWEA’s CEO.
Renewable electricity standards mandate the use of wind, solar and other easily replenished power sources in 39 countries and 29 states, including Texas and California. There is no similar nationwide mandate, though proposals for a federal requirement are pending in Congress.
A national renewable electricity requirement could steer utilities away from some lower-cost energy sources and encourage investment in wind and solar power.
Although an increasing number of states are adding wind power to their energy portfolios, turbines remain concentrated in the Great Plains and along the Pacific Coast. The industry has not secured a foothold in the Southeast, where less gusty conditions make the power source less attractive.
The nation’s six largest wind farms are in Texas, with the biggest “” the Roscoe Wind Farm near Abilene “” boasting 782 megawatts of generating capacity.
Bode stressed that wind power projects are spurring domestic manufacturing and said the industry supported 85,000 U.S. jobs in 2009. “We’re really one of the only bright spots out there in terms of growing the U.S. manufacturing sector,” he said.
Barry Broome slipped into San Francisco on a mission: Lure California-based solar companies to Arizona.
“I think there’s a lot of compelling technology in Silicon Valley that’s going to be able to be put to work in Arizona,” the chief executive of the Greater Phoenix Economic Council said recently in a downtown office tower lobby across from the U.S. headquarters of Yingli Solar, a Chinese solar module maker.
For decades, border states have raided California, enticing companies to pull up stakes by offering tax breaks, low-cost workforces, affordable housing and business-friendly bureaucrats.
But Broome says he was in California to deliver a different message: Arizona comes in peace. Yes, the state wants a share of California’s burgeoning solar industry, but it also wants to develop a cross-border solar industry that will benefit both states.
“We’re not interested in succeeding at the expense of California,” he said. “California’s going to need Arizona as an energy market and we need an export industry. We can’t continue to just live off housing and tourism.”
Arizona’s construction-dependent economy cratered with the collapse of the housing boom. The solar industry could anchor a more sustainable green economy, Broome said.
“When those solar power-plant projects are built, the amount of materials in them is staggering and there will need to be a place for component manufacturing,” he said. “A billion-dollar concentrated solar power project creates about a thousand construction jobs. So if you put $5 billion to $10 billion in the ground, it’s a nice set of jobs in a state that has a big slump in construction.”
Arizona and California increasingly find their renewable energy fortunes tied to each other.
Arizona-based companies First Solar and Stirling Energy Systems are building giant solar farms in California to supply electricity to Southern California Edison and Pacific Gas & Electric Co.
The European Union is prepared to pay 2.4 billion euros ($3.2 billion) a year through 2012 to help developing nations adapt to climate change as the 27-nation bloc bids to reinvigorate talks on cutting greenhouse-gas emissions.
“We need to restore confidence in the UN process and between the parties,” Alicia Montalvo said today in Bonn at a United Nations meeting in which the EU representative reiterated that billions in funding announced at the Copenhagen climate summit would be available starting this year. “We must all honor our commitments. We are prepared to do our part.”
Developed nations agreed to provide $30 billion to poorer nations over that period in the Copenhagen Accord for climate- change adaptation and mitigation efforts. Delegates from the Democratic Republic of Congo and Grenada criticized the way the Copenhagen summit was conducted, saying nations brokered deals outside of the main talks.
The Copenhagen summit was marred by “the emergence of a secret text put together by a select few,” Congolese delegate Tosi Mpanu Mpanu said. “These mistakes fundamentally broke the trust that is necessary for any partnership that is successful and enduring to work.”
Officials representing the 194 parties to the UN’s climate convention met today in Bonn to search for ways to advance climate negotiations after leaders failed to seal a binding agreement in Copenhagen.
President Obama is requiring an initial report from federal mine safety officials next week on the explosion at a West Virginia coal mine Monday that killed at least 25 workers, the White House announced Thursday.
The explosion at Massey Energy Co.’s Upper Big Branch mine – a mine that federal regulators have cited for numerous safety violations – is the nation’s worst mining accident in over two decades.
Obama has tasked the officials with producing an initial assessment on the causes of the accident and “what actions could prevent further tragedies in this industry,” the White House said.
Obama will meet with Secretary of Labor Hilda Solis and Mine Safety and Health Administrator Joe Main.
“He expects them to report on their early assessment of the deadly explosion’s cause, the safety record at the Upper Branch mine, and the steps that the Federal government should take to improve safety enforcement and prevent future tragedies,” the White House said. “The Secretary and MSHA Administrator will address safety issues as well as enforcement and legal authorities in their briefing.”