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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).

"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!"

Have you read the latest version of our, " #Power Engineering Guide"? You can here: http://t.co/K4GNOwCb #siemens

The Internal Combustion Engine: "I'm Not Dead Yet"

Wireless microcontrollers from silicon designer Jennic in Sheffield are being used to dramatically reduce power consumption in real world environments.

"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."

Thank God for Obama. We may survive yet.

I was browsing Greentech Media and learned about a Massachusetts aerospace company called FloDesign that's developed a new wind turbine design around the concept of a jet engine. This could allow for a more efficient wind turbine that produces two to three times more wind power than typical machines.

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.

The Schaeffler Group has therefore developed the Generation C range of deep groove ball bearings that not only offer 35 per cent less friction than their predecessors, but also cut noise levels by 50 per cent. This means a more efficient motor, resulting in reduced energy consumption, plus the new design improvements enable the bearings to run faster, while simultaneously increasing the operating life.

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

Environ Sci Technol. 2003 Dec 1;37(23):5414-6. Global sustainability and key needs in future automotive design. McAuley JW. Basell USA Inc., 912 Appleton Road, Elkton, Maryland 21921, USA. john.mcauley@basell.com Abstract The number of light vehicle registrations is forecast to increase worldwide by a factor of 3-5 over the next 50 years. This will dramatically increase environmental impacts worldwide of automobiles and light trucks. If light vehicles are to be environmentally sustainable globally, the automotive industry must implement fundamental changes in future automotive design. Important factors in assessing automobile design needs include fuel economy and reduced emissions. Many design parameters can impact vehicle air emissions and energy consumption including alternative fuel or engine technologies, rolling resistance, aerodynamics, drive train design, friction, and vehicle weight. Of these, vehicle weight is key and will translate into reduced energy demand across all energy distribution elements. A new class of vehicles is needed that combines ultra-light design with a likely hybrid or fuel cell engine technology. This could increase efficiency by a factor of 3-5 and reduce air emissions as well. Advanced lightweight materials, such as plastics or composites, will need to overtake the present metal-based infrastructure. Incorporating design features to facilitate end-of-life recycling and recovery is also important. The trend will be towards fewer materials and parts in vehicle design, combined with ease of disassembly. Mono-material construction can create vehicle design with improved recyclability as well as reduced numbers of parts and weight.