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Scientists are developing high-performance energy storage units, a prerequisite for effective hybrid motors.

REGENERATIVE BRAKING is widely practised, but there have to be other trains around to absorb the surplus power being fed back into the catenary or third rail. Processing the output from trains and pushing it back into the local grid is possible with an AC power supply, but very expensive with DC traction. Too often, power produced by traction motors in braking mode ends up heating resistor banks. The elegant alternative is to store the braking energy on the train. This not only avoids the electrical complications of regenerating through the traction power supply network. It reduces the rated power requirement of that network by lopping demand peaks during acceleration, saves energy by reducing losses in the catenary or conductor rail, and by limiting voltage drop it allows substations to be further apart. NiMH batteries have the necessary energy storage density in terms of kWh/kg, and are slightly more expensive, but their life in terms of charge/discharge cycles in no way matches the LRV requirement for 2million cycles over 10 years. Flywheels have been tried but never caught on for several reasons.

American Electric Power annouced that it is expanding its use of large-scale battery technology on its electricity grid by installing six megawatts of sodium sulfur (NAS®) batteries for storage of electricity to enhance reliability, allow for continued load growth, provide support for weak sub-transmission systems, avoid equipment overload and to offset intermittent wind power. AEP will be adding stationary sodium sulfur (NAS®) battery technology in its West Virginia and Ohio service territories next year. The company will also work with wind developers to identify a third location for NAS battery deployment ...to help offset the intermittent nature of wind generation.

U.S Deputy Secretary of Energy Clay Sell today announced that the Department of Energy (DOE) awarded the first three large-scale carbon sequestration projects in the United States and the largest single set in the world to date.

Industrial greenhouse gases prevented from entering the atmosphere through the use of so-called carbon capture and storage (CCS) technology are to be credited as not emitted under the EU emissions trading scheme, according to Commission plans to be put forward next year.

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.

Using "wrong-time" electricity from renewables to turn air into liquid may offer a solution to one of the great challenges in engineering - how to store energy. See it on Scoop.it, via Sustainable Energy via scoop.it

What's the key to using alternative energy, like solar and wind? Storage -- so we can have power on tap even when the sun's not out and the wind's not blowing. In this accessible, inspiring talk, Donald Sadoway takes to the blackboard to show us the future of large-scale batteries that store renewable energy. As he says: "We need to think about the problem differently. We need to think big. We need to think cheap."

"The team's research yielded a novel solution that combines the strengths of batteries and supercapacitors while also negating the scalability problem. The "electrochemical flow capacitor" (EFC) consists of an electrochemical cell connected to two external electrolyte reservoirs - a design similar to existing redox flow batteries which are used in electrical vehicles. This technology is unique because it uses small carbon particles suspended in the electrolyte liquid to create a slurry of particles that can carry an electric charge."

Wind power is, of course, controversial. A big knock is that until power-storage technology evolves, wind farms will work only when the wind blows. Wind energy proponents counter that the sites picked for wind farms are predictably gusty, though they acknowledge wind turbines will never be a complete answer to the nation's energy issues. But they say they can be a significant part of the our energy future when intelligently integrated with traditional power plants that have the ability to pick up the slack when wind doesn't deliver.