Wireless Power
Prototype Nokia phone recharges without wires
 Pardon
the cliche, but it's one of the holiest of Holy Grails of
technology: Wireless power. And while early lab experiments have
been able to "beam" electricity a few feet to power a light bulb,
the day when our laptops and cell phones can charge without having
to plug them in to a wall socket still seems decades in the future.
Nokia, however, has taken another baby step in that direction with
the invention of a cell phone that recharges itself using a unique
system: It harvest ambient radio waves from the air, and turns that
energy into usable power. Enough, at least, to keep a cell phone
from running out of juice.
While "traditional" (if there is such a thing) wireless power
systems are specifically designed with a
transmitter and receiver in mind, Nokia's system isn't finicky about
where it gets its wireless waves. TV, radio, other mobile phone
systems -- all of this stuff just bounces around the air and most of
it is wasted, absorbed into the environment or scattered into the
ether. Nokia picks up all the bits and pieces of these waves and
uses the collected electromagnetic energy to create electrical
current, then uses that to recharge the phone's battery. A huge
range of frequencies can be utilized by the system (there's no other
way, really, as the energy in any given wave is infinitesimal). It's
the same idea that Tesla was exploring 100 years ago, just on a tiny
scale.
Mind you, harvesting ambient electromagnetic energy is never going
to offer enough electricity to power your whole house or office, but
it just might be enough to keep a cell phone alive and kicking.
Currently Nokia is able to harvest all of 5 milliwatts from the air;
the goal is to increase that to 20 milliwatts in the short term and
50 milliwatts down the line. That wouldn't be enough to keep the
phone alive during an active call, but would be enough to slowly
recharge the cell phone battery while it's in standby mode,
theoretically offering infinite power -- provided you're not stuck
deep underground where radio waves can't penetrate.
Nokia says it hopes to commercialize the technology in three to five
years.
Christopher
Null
|
