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Courtesy: Lloyd Energy

Via Gizmag, word comes of one Australian town that is to go solar powered, 24-hours a day. How is that possible?

The technology used will ensure the 10 megawatt Cloncurry solar thermal power station will continue to generate electricity when the sun is not shining and will deliver about 30 million kilowatt hours of electricity a year. Up to 8000 mirrors will reflect sunlight onto graphite blocks through which water will be pumped to generate steam that will operate a conventional steam turbine electricity generator. Because heat stays in the graphite, the system will work through the night and on overcast days. Cloncurry, which is the first town in the State of Queensland to go totally solar, is a perfect candidate for solar thermal power generation, having long claimed the title of having recorded Australia’s hottest day - 53 degrees Celsius in the shade in 1889.

The system is being manufactured by the Australia-based Lloyd Energy Storage. The company has been conducting a feasibility study since 2007. Lloyd says the its steam system uses a once-through steam generator method combined with a air-cooled condensor and turbine. All water used is treated and recycled back through the system. The big deal in this story though is Lloyd’s energy storage system.

The key difference between this new technology and other solar power generation is the ability to store thermal energy at the point of collection and hold it before it is converted into electricity . This means that the storage losses are very low, thus making the system very efficient. The electricity generation system can, if required, run for 24 hours a day and also provide solar power on cloudy days.  The solar energy generation facility will comprise  a series of solar reflectors called heliostats which track the sun continuously and concentrate the beams of solar energy into a receiver cavity at the base of the storage blocks sitting on the top of small towers, the height of a small rural windmill. The blocks contain heat exchangers through which water is passed to generate steam and electricity using ordinary steam turbine generators. The energy storage system will enable power to be dispatched 24 hours a day if required, compared with conventional solar systems that only generate during sunlight hours.

The blocks are made of high-purity graphite so heat can be moved in and out very quickly. There is no intrinsic link to solar. It also could be used to store energy from wind and wave – really anytime there is a system that generates excess capacity or has a timing mismatch between generation and demand. The technology is the brainchild of Australian scientist Bob Lloyd. The company began as a project in the SMEC (nee Snowy Mountains Engineering Corp.). Lloyd says it has developed and patented a low-cost method of refining low quality graphite to create high quality crystalline graphite for the manufacture and use in the graphite heat storage block.

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. . . because, for better or worse, it works and is relatively durable, at least on the scale of lifetimes:

The model-derived estimate of the “in-use” cement stocks in the United States is in the range of 4.2 to 4.4 billion metric tons (gigatonnes, Gt). This indicates that 82% to 87% of cement utilized during the last century is still in use. On a per capita basis, this is equivalent to 14.3 to 15.0 tonnes of in-use cement stock per person. The in-use cement stock per capita has doubled over the last 50 years, although the rate of growth has slowed.

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Pay attention to this:

Tomorrow, Wednesday, February 18, U.S. Energy Secretary Steven Chu will deliver the opening keynote address at the 2009 DOE-NARUC National Electricity Forum. In the address, Secretary Chu will outline the Administration’s commitment to modernizing the nation’s electricity distribution system through a “Smart Grid” that will create new jobs, save consumers money, use energy more efficiently and avoid blackouts, and pave the way for a dramatic expansion in renewable energies such as solar and wind power. He will also discuss the immediate and long-term impacts of the President’s American Recovery and Reinvestment Act in creating jobs and investing in a clean energy future.

Update: C-Span is preparing to air Chu’s presentation. Update II: C-Span now has full video available here. One takeaway: Chu seems committed to cutting the bureaucracy and getting the funding and loans moving. He says applications that now require 500-1000 pages are getting cut to 50 pages.

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Via CNET’s Green Tech blog, we bring you a video about some nifty power conversion technology for photovoltaic applications that Freescale Semiconductor unveiled this week at the Applied Power Electronics Conference and Exposition. This is about high efficiency, ultra-low-voltage DC-to-DC converter technology. It enables IC startup thresholds to be reduced to 0.32 V (ICs typically can’t start up at less than 0.7 V) and efficiencies of nearly 90 percent. This method would allow new system design options and the ability to recover energy at ultra-low voltages, e.g., single-cell solar power systems and other energy-harvesting applications, such as thermoelectric and mechanical scavenging systems. “Freescale says applications can include solar-powered battery chargers, trickle chargers for automotive systems, chargers for cell phones and laptops, remote data acquisition and industrial HVAC systems, PV-based traffic signals, solar-powered home and commercial lighting products, and self-powered wireless transponders.”

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Grad student Martin Duran and Azad, right, working on the processing of nanoscale ceramic catalysts.

(the following is a guest post from Abdul-Majeed Azad, associate professor, chemical engineering, University of Toledo)

As we know, the ultimate chemical fate of the conventional fossil fuel combustion is always CO₂ and H₂O, two well-known greenhouse gases responsible for contributing considerably to the global warming. In 2007 the global level of CO₂ was 30 billion metric ton and is projected to be 43 billion metric ton by 2030. The United States contributes the largest amount - 22.2% - of global CO₂ emissions.

What if we could convert CO₂ into carbon monoxide (CO), water into H₂ and a mixture of CO₂+H₂O (the ultimate product of complete combustion of hydrocarbon-based fossil fuels, including biofuels) into syngas (CO+H₂), respectively? Syngas is a valuable precursor for the well-known Fischer-Tropsch process perfected by Germans during WW II to make synthetic fuels since Germany had coal but no oil reserves. All these streams (CO, H₂ and CO+H₂) are also ideal fuels for solid oxide fuel cells. Hence, essentially the waste products of combustion could become a fuel source and can be recycled. Alternatively, if desired, CO could be converted into H₂ via catalytic water-gas-shift reaction that then could become feed for proton exchange membrane fuel cells.

We have developed an inexpensive heterogeneous ceramic catalyst that we experimentally found capable of converting CO₂ and H₂O into CO and H₂, respectively, on a 1:1 molar basis, under mild temperature and atmospheric pressure. These streams when fed into an intermediate temperature SOFC at 650°C create an open circuit voltage, quite comparable to that of the same SOFC run with pure H₂.

The technology is also of relevance to NASA’s in-situ resource utilization program for MARS exploration since Martian atmosphere is ~ 96% CO₂. NASA might be interested in looking at our technology for creating CO from Martian CO₂ and, use it either as such or after water-gas-shift reaction to generate hydrogen as fuel for a SOFC stack. In the Martian context, to make the process truly self-sustained one could use solar concentrators to generate enough heat to raise the temperature to cause the desired conversion (CO₂ to CO to H₂). Thus, the fuel can be generated (and used) during daytime and stored and utilized to run fuel cells in the night hours.

It is predicted that global clean energy markets are going to quadruple in the next decade from $55.4 billion in revenue in 2006 to more than $226.5 billion by 2016. The approximate market size of this greenhouse gas mitigation is over $1 billion. The technology and the product are potentially of interest to energy producers and suppliers, utility chains, SOFC manufacturers and users, organic synthesis companies and Mars human exploration missions. The United States Department of Defense uses logistic fuels for its operations and could employ the greenhouse gas-fueled SOFC technology for many military field operations, including mobile forward base units, auxiliary field hospitals, field command posts, operational forays, and unmanned aerial vehicles. NASA is also currently looking at non-petroleum-based jet fuels in the pursuit of alternative fuels that can power commercial jets and address rising oil costs. A greenhouse gas-derived F-T fuel could respond to that quest.

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