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A novel form-stable phase change wallboard (PCW) was prepared for low-temperature latent heat thermal energy storage by incorporating eutectic mixture of capric acid and stearic acid and gypsum wallboard. Thermal properties of form-stable PCW were measured by DSC analysis. The form-stable PCW has good thermal reliability with respect to the changes in its thermal properties after accelerated thermal cycling.

After emerging in 2006 from 15 years of hibernation, the solar thermal power industry experienced a surge in 2007, with 100 megawatts of new capacity coming online worldwide. During the 1990s, cheap fossil fuels, combined with a loss of state and federal incentives, put a damper on solar thermal power development. However, recent increases in energy prices, escalating concerns about global climate change, and fresh economic incentives are renewing interest in this technology.

Fred Pearce has framed his latest opinion piece in Yale Environment 360 as one about Europe fiddling around with its climate change commitment (with German Chancellor Angela Merkel as lead violin), while the US is poised to reengage with the world under the Obama administration. What it's really about though is what the US would need to do to take that lead, and it all has to do with renewable energy. Though some of this may be recap for avid TreeHugger readers, it's worth repeating: Stephen Chu Appointment a Good Sign Beyond his stated commitment to dealing with climate change during the campaign, Pearce indicates that the appointment of Stephen Chu as energy secretary is the real sign that the US could soon lead the renewable energy/climate change race. Not only has he done pioneering research on solar power, energy efficiency and cellulosic biofuels at the Lawrence Berkeley National Laboratory, he's also an advocate of a nationwide expansion of the electric grid to bring renewable energy from where it's most easily generated (west of the Mississippi) to where the greatest demand is (east of the river).

The significance of the thermal stratification for the energy efficiency of small solar thermal hot water heat stores is pointed out. Exemplary the thermal stratification build-up with devices already marketed as well as with devices still in development has been investigated experimentally and theoretically, taking into account different realistic operation conditions.

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.

The European market for solar thermal systems is in the transition phase. Over the past 4 years the market has undergone considerable changes, as the interest it receives from policy makers, industry players and end users is ensuring strong growth trends in the coming years.

Ocean Thermal Energy Conversion (OTEC), a clean, renewable energy source that has the potential to free many economies from their dependence on oil.

When completed in 2011 this thermal solar project will be the largest in the world, generating 553 megawatts of power for Pacific Gas & Electric in the Mojave Desert in California. The plant is being built by Israeli company, Solel Solar Systems of Beit Shemes, Israel, a successor company to the people that built the nine thermal solar plants in the Mojave Desert, that have operated over the past 20 years and are currently generating 354 MW of electricity.

The Canadian government boosted its incentives for home energy retrofits yesterday by 25 per cent for most items, which the Ontario government said it would match. It's all part of an effort to stimulate "green" home renovations as part of a larger effort to kickstart economic activity.

The storage of cold with ice slurries - a special type of thermally multi-functional fluids or phase change slurries (PCS) - is discussed. At first an example of a calculation of a thermal energy storage tank in an ice slurry system with a peak load demand is presented.

The California Energy Commission (CEC) recently approved the nation's most stringent energy efficiency standards for residential and commercial buildings, and the new requirements for the thermal performance of windows are expected to contribute ...

Batteries have to contain all of the chemicals on both sides of their energy releasing equation. The very best batteries available today can store about 0.4 MJ/kg (0.05 kw-hr/lb) including the cases and safety systems. In contrast, gasoline carries about 46 MJ/kg (5.7 kw-hrs/lb).\n\nEven with a 20% efficient IC engine, a gasoline tank stores 20 times as much energy as a battery of equal weight. As the vehicle is moving it gets rid of some of that weight. Battery powered vehicles must carry the full weight of their energy source.\n\nThe energy density difference also plays a key role in the time that it takes to put more energy back on the vehicle once a fuel load is consumed. A two minute fill-up of a 12 gallon tank puts the equivalent of 87 kilowatt-hours into the vehicle, again, taking into account the 20% thermal efficiency.\n\n87 kilowatt-hours in 2 minutes works out to 2.6 MegaWatts. Even with a 220 volt connection, that would require about 11,800 amperes of current. Just imagine the size of the electric cables for that current.\n\nThere are certainly places and applications where electric vehicles have a role, but it is worth remembering that at least five or six generations of engineers have looked very hard at trying to meet transportation needs and they keep coming back to the same fact - when you want to move a vehicle, you need power, (energy per unit time).

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.

serious problems are being raised by a generation of nuclear power plants going out of business for reaching their end of life. who, what will replace them? at what economic and environmental cost?