Japanese move forward on wireless power using microwaves!
Much more efficient than using wires!
The Japanese are now developing a space based satellite to collect huge amounts of solar power, which is then converted into microwaves , transmitted to a Receiving antenna on the ground, and converted into DC energy for electrical use.
The receiving antenna (rectenna) converts the microwaves into DC power by taking the microwave in through the regular receiving antenna, then passing the signal through a Rectifying Diode, which then usually passes through a Low Pass Filter, which then ultimately passes into a DC to DC step up / step down “buck converter” — to scale up the power or scale down the power for using regular household electric powered items.
Much more on rectennas here:
How does the wireless power transmission process actually work? find out much more on the science behind the process here:
Whatever signal the antenna picks up is originally in “AC” inside the antenna, thus a “rectifying diode” is needed to obtain useable steady voltage… rectifying the radio wave into DC voltage.
I suppose the amperage would ultimately depend on the number (or size) of the input antennas , and the rating of the diode being used to rectify the microwave signal into useable power.
2.45GHz – 5 GHz also just so happens to be a common wi-fi frequency used by most 802.11 systems on our computers, mobile phones, and tablets. Bluetooth also operates (usually) in the 2.4GHz microwave range.
2.45GHz also cooks your food in your kitchen microwave (at 1000Watts) 🙂
Full article in the news over the past 2 weeks:
“Japan Space Agency Advances in Space-Based Solar Power
It’s one small 55-meter step for Japan’s aerospace industry, but perhaps a giant leap into developing a new energy source for mankind.
The Japan Aerospace Exploration Agency, or Jaxa, said it succeeded in transmitting electric power wirelessly to a pinpoint target using microwaves, which is an essential technology needed for the realization of space-based solar power.
According to a spokesman at the agency, the researchers were able to transform 1.8 kilowatts of electric power into microwaves and transmit it with accuracy into a receiver located 55 meters away. The microwave was successfully converted into direct electrical current at the receiving end. The experiment was conducted Sunday in Hyogo prefecture in western Japan.
In space-based solar power generation, sunlight is gathered in geostationary orbit and transmitted to a receiver on earth. The Jaxa spokesman told Japan Real Time that Sunday’s experiment was the first in the world to send out high-output microwaves wirelessly to a small target.
According to the U.S. Department of Energy, more solar energy reaches the earth every hour than humans use in a year. Unlike solar panels set on earth, satellite-based solar panels can capture the energy around the clock and are not affected by weather conditions.
If implemented, microwave-transmitting solar satellites would be set up approximately 35,000 kilometers from earth. Jaxa says that a receiver set up on earth with an approximately three-kilometer radius could create up to one gigawatt of electricity, which is about the same as one nuclear reactor.
It’ll be many years before that happens, if it ever does. Researchers “are aiming for practical use in the 2030s,” Yasuyuki Fukumuro, a reasearcher at Jaxa, said on its website.
While the energy is transmitted in same microwaves used in microwave ovens, it does not fry a bird or an airplane traveling on its path because of its low energy density, according to the Jaxa spokesman.”