File this under, “Technology I Never Knew Existed,” but Nokia says that in a few years time, they will be able to charge cell phones by using ambient radio waves. This intriguing and exciting technology could lead to huge reductions in energy demand if every cell phone could pull a charge of juice out of thin air.
Researchers at the Nokia Research Centre in Cambridge in the UK are working hard on a technology that can harvest small amounts of energy from ambient radio and TV waves. The cell phone would pick up radio wave frequencies as low as 500 megahertz up to 10 gigahertz, which includes television broadcasts, microwave ovens, mobile phones, wireless LAN, bluetooth, GPS, and two-way radios. In theory, two circuits would be capable of receiving and then converting the free energy to an electrical current to charge the battery of a cell phone.
Hopefully, it would be enough energy to keep the phone charged in standby mode; although at first it won’t be enough to charge the phone while in use, or to full battery capacity. Markku Rouvala, one of the researchers who developed the device, says “trick here is to ensure that these circuits use less power than is being received.” So far, their device can collect up to 5 milliwatts of power, and their short term goal is to collect 20 milliwatts of power, which is just enough to keep the phone charged in standby mode. Ultimately, 50 milliwatts of power would be ideal and could help slowly recharge the battery.
This technology could be applied to other electronic equipment as well. Radio waves could be used to charge MP3 players, handheld devices, Kindles, portable game players, etc. Nokia isn’t relying on this type of technology alone to power their phones, they are also looking at integrated solar cells to work in conjunction with this new development. Deployment of this feature in Nokia phones is still at least 3 years away. We’ll be standing by with our waning cell phones waiting for word.