Group Actions
Engagement
  • Author Author: Catwell
  • Date Created: Date Created
  • Views 609 views
  • Likes 4 likes
  • Comments 2 comments
Related
Recommended

Stanford Researchers Redefine “Electricity on the Go”

Catwell

image

Stanford University consistently brings us innovation. It’s astounding. An example of that is the team of engineers who created a clever way to transmit electricity wirelessly. The technology could send electricity to moving electric cars, drones and robots, and could be applied to electric cars driving on the highway or drones flying in the sky after it is scaled up.

 

Although a revolutionary idea, wireless electricity is a project, the team had been working on for a while now. Shanhui Fan and Sid Assawaworrarit, the two researchers working on the project, confessed that the initial prototype was not reliable enough to be used outside the lab. About three years ago, the researchers developed a charging tool that could charge a receiver even when the distance to the latter fluctuated. The feat was possible thanks to the combination of an amplifier and a feedback resistor, which permitted adjustments to the operating frequency despite the constant change in distance. Unfortunately, the system could only transmit ten percent of the power it generated, output, which has now been improved.

 

For the new version of the system, the researchers replaced the original amplifier with a “switch mode” amplifier, which allowed the system to transmit more than 90 percent of the electricity flowing through it. With this improvement, the researchers would be able to transmit about 10W of electricity to a receiver as far as 3 feet away. Fan and Assawaworrarit are confident that it will not take much more to bring the system to the level where it transmits hundreds of kilowatts to an electric car. According to their calculations, it will be possible to charge a car going at 70 miles per hour in a fast manner if it goes through a charging area of approximately 4 feet.

 

We are talking about a super-fast charging on the fly, which brings up the questions of whether the battery of the electric cars on the market can absorb electricity that fast. Super caps? I’m not at all certain that much intense energy blasted at people constantly would be safe despite the researchers assure us that their technology presents no risk for the human body.

 

Have a story tip? Message me at: cabe(at)element14(dot)com

http://twitter.com/Cabe_Atwell

 

 

  • in reply to michaelkellett

    Prize awarded!

     

    Just reporting what they said. Electrifying the roadway in any capacity will lead to a darwin award at some point. 

     

    However, even if it has a terrible efficiency in real world tests... it's a great step forward.

  • Oh come on Cabe - engage brain here !

     

    All numbers approximated to about 1 sig fig

    4 feet = 1.2m

    70 mph = 31m/s

    Time through charger = 0.04s

    Assume charge power of 1MW at 100% efficiency - car receives 1e6 * 0.04 = 4e4 joules

    4e4 joules = 4e4/3.6e6 = 0.01kWh

    So a car needing a reasonable 50kWh charge needs to pass the charger 5000 times !

     

    Or it needs pass 5000 chargers - spanning a distance of 40000 feet = 8 miles

     

    At 70mph the cars should be at least 250 feet apart so only 160 cars can be in the charging zone at a time - so only 3.2% of the chargers are active at time.

     

    Now just how much do you think 1MW remote chargers will cost, could they be safe ..........

     

    The car owners could just plug them in at night.

     

    A better scheme might be to give those guys washing windscreens at junctions a nice 100kW cable to plug into your car while they wash. Proven technology, jobs for the unskilled, no nasty magnetic fields.

    Can I have a Nobel prize please image

     

    MK