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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).

"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."

For at least a decade, carmakers have been professing their deep and abiding interest in electric-drive vehicles whenever possible. But until recently, it wasn't always clear which of them were really sincere. Today every last one of them seems sincere. As this year's "Top 10 Tech Cars" package shows, ever more varied hybrids are going into mass production, along with-you betcha-a few all-electric cars. Some of the electric-drive machines aspire beyond mere greenness to heart-pounding performance, an aspiration that may seem strange to those taught to view electric cars as spacious, all-weather golf carts. But performance is indeed a logical goal, given the instant-on torque that electric motors provide. While electrons may now be a recurrent theme of our annual Top 10 automotive reports, we do not slight the internal-combustion engine, which has lots of life-and technological enhancements-to come. And for those who don't spend a whole lot of time worrying about whether they're treading lightly enough on the planet's roads, we include two ultraperformance German sports cars that run purely on gasoline and adrenaline. One can easily be yours. If you're willing to trade in your house for it.

"Displacer-type Stirling Engine Instead of having two pistons, a displacer-type engine has one piston and a displacer. The displacer serves to control when the gas chamber is heated and when it is cooled. This type of Stirling engine is sometimes used in classroom demonstrations. You can even buy a kit to build one yourself!"

Palestinian engineers say it only costs $1.50 per fill-up. Israel is also going electric with hundreds of charging stations to be installed nationwide

After Portugal, it appears that Israel is the second country to develop a network of charging stations.

The process, Current says, lets a utility more efficiently manage the distribution of electricity by allowing two-way communication between consumers and energy suppliers via the broadband network on the power lines. Based on data they receive from hundreds of homes, utilities can monitor usage and adjust output and pricing in response to demand. Consumers can be rewarded with reduced rates by cutting back on consumption during peak periods. And computerized substations can talk to each other so overloaded circuits hand off electricity to underused ones, helping to prevent blackouts.

Talking about turning the world upside down.

US engineers are working on a device that could harness the power of slow-moving water currents in oceans and rivers to generate electricity.

300 years after its invention, Stirling engines are coming to stay... and probably take a nice share of the Solar Power market. the cost perspective is also quite attractive. these structures cost now around $20 000 against 50 to $100 000 3 years ago.

Thank God for Obama. We may survive yet.

Electric motors as the prime movers in all industry sectors are a major example. Generally regarded as highly reliable, due to tried and tested construction techniques, they are, nevertheless, subject to number of harmful conditions that can affect their performance and reduce operational life. One of the most common of these conditions is vibration, resulting from either electrical or mechanical imbalance in the motor.