Nikola Tesla wanted to beam power without wires. NASA talked about building power-generating satellites that would do the same thing. But now New Zealand’s second-largest power utility — Powerco — is working with a start-up company to beam energy to remote locations. There have been several news releases, but possibly the most technical detail is from an interview [Loz Blain] did with the founder of the startup company.
It isn’t really news that you can send radio waves somewhere and convert the signal back into power. Every antenna does that routinely. The question is how efficient is the power transmission and — when the power levels are high — how safe is it? According to [Greg Kushnir], the founder of Emrod, the technology is about 70% efficient and uses ISM frequencies.
According to [Kushnir], the technology relies on metamaterials that are very efficient and a beam that sends all the power to the receiver, possibly through some passive relay stations [Kushnir] claims are like lenses and nearly lossless. Reading between the lines, it sounds like a modern take on the MASER with very good receiving antennas.
The relay antennas allow you to send power beyond your line of sight. Apparently, the power density is not enough to be very harmful if you intersect the beam for brief times, but a laser sensor can stop some part of the energy flow if something obstructs the beam.
Is it real? We don’t doubt it is possible. Their existing prototype sends a few watts about 40 meters, which is not a big deal. The new system will transmit “a few kilowatts” for a longer distance. The real question is can you safely operate at power levels that make economic sense based on actual efficiency. Honestly, 70% isn’t that great and even that sounds like it would be difficult to achieve over a long distance. But Powerco must see some promise in the technology, so we’ll wait and see how it goes.