The Plugless Power system uses a parking block and a shoebox-sized vehicle adapter that needs to be installed under the car ahead of the front wheels. The block contains a transmitter that can move within the box and and thus get as close as possible to the receiver on the car. The distance should be around two inches max in order to send the electricity to the vehicle. If it's out of range, the system's tower – tall and visible from inside the vehicle – will warn the driver to repark before it will power up the vehicle. It won't send out a low-efficiency charge if the transmitters are, say, six inches apart. You can compare it to digital radio that just cuts out when it's out of range instead of a traditional FM signal that gets weaker and weaker the further away the tower is.
This December, the company will release its first-generation model, which, kind of ironically, uses a cord. This unit will provide Level 2 (240 volt, 32 amp) charge through a J1772 connector. These units will cost around $3,000 and can be upgraded to the wireless units for another $800 when those become available in April 2011 (installation fees extra). Installing the receiver in the vehicle will cost around $500, but that's not officially set, yet, so this isn't a cheap set-up. Thankfully, if you like the idea of wireless charging, it is eligible for the $2,000 in government incentives. Evatran is taking orders for the first-gen units now, but the price to just straight-up buy a plugless unit was not announced. Evatran will offer a one-year warranty on the units.
While recharging without any extra work is appealing, there's a big problem with Plugless Power's unit. Specifically, it's not 100 percent effective. Evatran's Rebecca Hough said that the company is targeting a 90 percent efficiency rate before releasing the product (right now, they're around 80 percent). While that's pretty amazing considering you're sending energy through the air, it also means that your electric vehicle automatically becomes less efficient with proximity charging than it would be with a cord. Yes, there are transmission losses along the grid, but when you take 10 percent away right before the energy gets to the car, that's a real shame.
Still, wireless recharging is a technology that bears watching, whether it comes from Evatran or Intel or whoever. Evatran looks like it'll be a player – it is working on getting UL listed and is talking with OEMs and niche players to have wireless chargers being an option at the time you buy a vehicle. The company started researching the idea 18 months ago, came to Plug In 2009 and, two months ago, got $1.25 million from the state of Virginia's Tobacco Indemnification and Community Revitalization program. So, things are moving fast, and we'll try to keep up.
[Source: Plugless Power]