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Lost the article, but it states in 5-10 years appliances like computers may not be plugged in but get powered wirelessly. Some have concerns with EMFs, but my concern is will this increase energy consumption at a time we don't need it?

Yes, it will increase energy consumption. The energy recieved decreases either by the square of the distance away from the transmitter, or possibly the cube of the distance. (I forget which.) So to go over any real distance at all means you have to pump a lot of power into the air, which is very wasteful. And that ignores any side-effects, e.g. potential health problems.

Wireless is OK for signals, which can be very weak and still be useful. Not so good when trying to transmit actual power.

-soD

If existing radio stations are used as the transmitters, there will be no extra load on the grid.

Tesla believed it was possible to transmit electricity cheaply without wires, this Wiki link has some additional information

http://en.wikipedia.org/wiki/Wireless_energy_transfer

When I first read about this a few years ago, some researchers were showing off a table lamp with no cord, saying they thought they could get to 50% transmission efficiency across a room. I thought there were more pressing matters to research, but you can't go wrong making a new way for Americans to waste energy. You can't have electric cords showing, you know. Only low class people use electric cords!

I don't think we'll see high or even medium amounts of wireless power transmitted in the near future (in the house). I think it will only be the small low power devices - You'll have a pad you throw your ipod or cellphone on and it charges without you having to plug in a chord. However as far as transmitting signals, I expect that to go way up. I think in 10 years for computers the only cables you'll need to connect will be the power cables, and you'll be able to do fancy things like transmit songs from your computer straight to your car's mp3 player, even from quite a distance away.

great video showing a TV being Safely powered without wires.
cool demo, it has a LOT of promise for charging small things like cell phones. but for large things like a Car the 50% efficient in transmission would be an issue.


http://www.ted.com/talks/eric_giler_demos_wireless_electricity.html

If you use the technology to charge cars from existing radio stations, 50% efficiency isn't bad, since the current efficiency is exactly 0%. It would solve the problem of getting power to the cars while they are driving, too.

If it's as reliable as my wireless mouse/keyboard we chucked, then no I don't think it's a good thing.

If existing radio stations are used as the transmitters, there will be no extra load on the grid.

And there will be no useful power received at the intended loads.

For anyone who has any concerns about energy efficiency, or about EMF from power lines or electric appliances, this appears to be a giant step backwards.

And there will be no useful power received at the intended loads.

For anyone who has any concerns about energy efficiency, or about EMF from power lines or electric appliances, this appears to be a giant step backwards.
The receivers can be programmed to only operate if the hybrid battery is below 50% (to maintain a reserve for regen) and the car is actually being driven. I remember about an algorithm for fairly sharing power among loads, which can be useful in this application. Parked cars can be designed to only draw power for battery charging if there are no driven cars drawing power in the area or simply not draw power at all.

Or use one large receiver to run a hydrogen generation plant and avoid the power sharing problem, but that introduces more inefficiency... But with current radio energy efficiency at exactly 0%, even 10% is a good start. There's many megawatts of energy being thrown away and turning to useless heat in the environment.

Or use one large receiver to run a hydrogen generation plant and avoid the power sharing problem, but that introduces more inefficiency... But with current radio energy efficiency at exactly 0%, even 10% is a good start. There's many megawatts of energy being thrown away and turning to useless heat in the environment.

How are existing radio stations going to be able to use this method of transmitting of power wirelessly? With or without drawing extra power from the grid?

From everything I understand, radio communications will stay at ~0% power transmission efficiency, because they were never intended to transmit power, only signal. The best way to get them involved in energy efficiency is to abolish analog formats and convert them of digital formats, cutting radiated power by ~90%.

How are existing radio stations going to be able to use this method of transmitting of power wirelessly? With or without drawing extra power from the grid?

We could go full circle on radio tranmission and go (power) cordless again

http://3.bp.blogspot.com/_IoU3bEFUwWc/SAeL1YK4-rI/AAAAAAAAAn8/sTTuq0CwOMo/s400/Crystal+6.jpg

Anyone know where I'm going?

How are existing radio stations going to be able to use this method of transmitting of power wirelessly? With or without drawing extra power from the grid?

From everything I understand, radio communications will stay at ~0% power transmission efficiency, because they were never intended to transmit power, only signal. The best way to get them involved in energy efficiency is to abolish analog formats and convert them of digital formats, cutting radiated power by ~90%.
http://ca.tech.yahoo.com/blogs/the_working_guy/rss/article/3638
Just scale up the technology.

http://ca.tech.yahoo.com/blogs/the_working_guy/rss/article/3638
Just scale up the technology.

It will have to scale up a long, long, long, long way, and require an oversize load permit to fit onto the highway.

The phone prototype you point to now harvests 5mW, with aspirations of reaching 50mW. Not enough for an active phone conversation, only enough for a very slow recharge while on standby.

Scaling this up to automotive power, say 1kW for charging while it is parked overnight, will require an antenna 200,000 times larger than that of this phone. It looks like about 2"x4", or 8 in^2, so the car charging antenna will be about 100 feet tall x 100 feet wide. Building codes won't permit that size structure on my single-family-residence property. PV solar panels will be far more compact for the same energy collection, even here in cloudy Seattle.

For transportation purposes, this is a non-starter.

It will have to scale up a long, long, long, long way, and require a oversize load permit to fit onto the highway.

The phone prototype you point to now harvests 5mW, with aspirations of reaching 50mW. Not enough for an active phone conversation, only enough for a very slow recharge while on standby.

Scaling this up to automotive power, say 1kW for charging while it is parked overnight, will require an antenna 200,000 times larger than that of this phone. It looks like about 2"x4", or 8 in^2, so the car charging antenna will be about 100 feet tall x 100 feet wide. Building codes won't permit that size structure on my single-family-residence property. PV solar panels will be far more compact for the same energy collection, even here in cloudy Seattle.

For transportation purposes, this is a non-starter.
Receiving more power does *not* really mean a bigger antenna, since it is frequency that controls antenna size. It does mean that a higher Q factor would be needed, which would likely mean superconductors.
http://amasci.com/tesla/tesceive.html

What could get interesting is if radio energy receivers and solar panels could be integrated onto the same piece of silicon without negatively affecting the performance of either. Then you'll have a solar panel that would still generate some electricity at night since radio waves exist 24/7.