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Even on the moon, superconductors would need to be cooled.

By Jorge Moreno, Environmental and Building Technologies, Frost & Sullivan With more end users focusing on reducing energy costs, energy-saving water-to-water heat pump (WTWHP) chillers are being deployed to reduce a facility's utility bills. A WTWHP chiller is a water-cooled chiller that is designed to produce hot water at a specified temperature. The use of a WTWHP chiller is very similar to a conventional centrifugal chiller except for the fact that it uses two compressors, slightly different piping configurations, and more advanced controls in order to balance cooling and heating loads. In a conventional chiller, cold water is produced for comfort cooling, and the hot water that is extracted from the refrigeration process goes into a cooling tower and is released into the atmosphere. In a WTWHP chiller, this hot water is captured and relocated to a second heating stage, where the temperature is raised and the water is used as a heating source for a building's heating requirements. The key strength of WTWHP chillers is the high coefficient of performance (COP) that translates into significant energy savings and a shorter payback period. On the other hand, the key weakness is that it can only provide such benefits in a narrow range of applications primarily due to its coincident need for cooling and heating requirements throughout the year to ensure efficiency. A coincident need means that the application demands sizable water heating load along with the typical high cooling requirements in summer, and a sizable chilled water load along with the typical heating requirements during winter. Cooling output is directly dependent on the demand for heating, and vice versa. Consequently, in the absence of sufficient heating requirements, there is only a limited amount of cooling that can be produced. Any excess heating or cooling cannot be stored and hence, it is critical to align the cooling with the expected heating requirements. Coincidentally, in the absence of suf

When the motor runs above a certain speed, the shaft rides on a magnetic cushion, not on bearings, eliminating the metal-on-metal wear all together. The motor produces no heat but runs at ambient temperature.

They put a positive spin on this finding, suggesting that there's more thermal energy for home and residential heat-pump systems to tap, and that this energy will displace the use of fossil fuels. Hardly something to cheer about, however, given the initial causes of the warming.

Ocean Power Technologies, Inc (OPT) and Converteam Ltd. recently signed a Cooperation Agreement for the development of High Temperature Superconductor (HTS) Linear Generators for use in OPT's PowerBuoy wave energy converters. "HTS is a truly disruptive technology the advantages of which will radically change wave energy capture. Converteam is looking forward to working with OPT on this exciting and challenging new project." -- Derek Grieve, Technology Director, Converteam Ltd. The vision of the two companies is the direct conversion of the linear up and down motion of waves into electricity using OPT's PowerBuoy and Converteam's HTS linear generator. The proposed power take-off for the OPT PowerBuoy will employ Converteam's innovative and proprietary linear generator system with high temperature superconductors to provide the magnetic field.

The important point, missed in this page and the comments on it, is that the energy is stored as latent heat of fusion. The mass is effectively a constant temperature heat sink/source over a wide range. There is nothing new in the world of course - this approach was extensively studied at BICC Research in the early 70's for peak lopping/load shifting for heating systems. The materials studied then had melting points in the 30 - 40 C range, but I don't remember the latent heat values. At that time it was rejected as too large and heavy - then the oil crisis passed. How does it compare with flow cells?

CONVERTING a greenhouse gas into a clean-burning fuel offers two benefits for the price of one. That's the thinking behind a novel process for converting carbon dioxide into methanol at room temperature, developed by a team at the Institute of Bioengineering and Nanotechnology in Singapore (Angewandte Chemie International Edition, DOI: 10.1002/anie.200806058).

Very interesting presentation at the TED Conference.  Not quite a nuclear battery, but a really good redesign of nuclear power systems. excerpt: "Instead of finding a new way to boil water, Wilson's compact, molten salt reactor found a way to heat up gas. That is, really heat it up. Wilson's fission reactor operates at 600 to 700 degrees Celsius. And because the laws of thermodynamics say that high temperatures lead to high efficiencies, this reactor is 45 to 50 percent efficient. Traditional steam turbine systems are only 30 to 35 percent efficient because their reactors run at low temperatures of about 200 to 300 degrees Celsius. And Wilson's reactor isn't just hot, it's also powerful. Despite its small size, the reactor generates between 50 and 100 megawatts of electricity, which is enough to power anywhere from 25,000 to 100,000 homes, according to Wilson. Another innovative component of Wilson's take on nuclear fission is its source of fuel. The molten salt reactor runs off of "down-blended weapons pits." In other words, all the highly enriched uranium and weapons-grade plutonium collecting dust since the Cold War could be put to use for peaceful purposes. And unlike traditional nuclear power plants, Wilson's miniature power plants would be buried below ground, making them a boon for security advocates. According to Wilson, his reactor only needs to be refueled every 30 years, compared to the 18-month fuel cycle of most power plants. This means they can be sealed up underground for a long time, decreasing the risk of proliferation. Wilson's reactor is also less prone to proliferation because it doesn't operate at high pressure like today's pressurized-water reactors or use ceramic control rods, which release hydrogen when heated and lead to explosions during nuclear power plant accidents, like the one at Fukushima in 2011. In the event of an accident in one of Wilson's reactors, the fuel from the core would drain into a "sub-critical" setting- or tank-

This paper is focussed on thermal storage technologies using phase change materials (PCMs) in the temperature range of 120-300°C for solar thermal power generation and high temperature process heat. As the state-of-the-art reference system a steam accumulator is described, which typically has a volume-specific thermal energy density of 20-30 kWh m-3.

Some countries have vintage whiskey. Some have vintage wine. Greenland has vintage ice. Sometimes you just wish you were a photographer. I simply do not have the words to describe the awesome majesty of Greenland's Kangia Glacier, shedding massive icebergs the size of skyscrapers and slowly pushing them down the Ilulissat Fjord until they crash into the ocean off the west coast of Greenland. There, these natural ice sculptures float and bob around the glassy waters near here. You can sail between them in a fishing boat, listening to these white ice monsters crackle and break, heave and sigh, as if they were noisily protesting their fate. Greenland is one of the best places to observe the effects of climate change. Because the world's biggest island has just 55,000 people and no industry, the condition of its huge ice sheet - as well as its temperature, precipitation and winds - is influenced by the global atmospheric and ocean currents that converge here. Whatever happens in China or Brazil gets felt here. And because Greenlanders live close to nature, they are walking barometers of climate change.

Rather than use a working fluid to capture and transfer the waste heat, GE has developed a new evaporator to transfer it. The new design means that ORCs can be used to convert relatively low-temperature heat (under 500 degrees Celsius) into electricity on a wide range of power sources, including the equipment in coal power plants and small gas turbines, said Thomas Fry, a researcher in GE's Munich offices.

A material that splits water into oxygen and hydrogen at room temperature using relatively little electricity could be an important step toward affordable chemical storage of solar power.

In an arid region of the western U.S. known as the Great Basin, the desert floor has recently been reaching temperatures in excess of 1,300 degrees Farenheit. No, this isn't due to global warming, but perhaps part of the solution to it. A Utah based company called IAUS (International Automated Systems Inc.) has developed a solar lens technology that transmits solar energy with an efficiency of 92%.

Penn State University scientists and the Virginia Commonwealth University have found something that is the ultimate dream and hope of alternative energy researchers: use water as a fuel. Their findings show that water can be split into its two constituents, hydrogen and oxygen, at room temperature and without any external energy addition. For that matter, they expose water to selected nano-engineered clusters of aluminum, acting as catalysts. What's shocking and interesting is the new approach, detaching from the centuries-old premise that water can only be split by electrolysis, using a high amount of energy.