Wireless electricity is coming, and it could power your home in the near future. Since the inauguration of Manhattan’s first power plant in 1882, electricity has always traveled via wires. However, this dependence on physical infrastructure could soon come to an end thanks to a technology that promises wonders: “power beaming”.
The technology envisaged by Tesla in 1901 is starting to take shape: it will soon be possible to power entire homes without any wires.
The concept is based on the emission of electromagnetic waves such as microwaves, radio waves and lasers to send energy from one point to another, wirelessly. A space solar power plant could, for example, transmit up to 1 gigawatt of energy (the equivalent of a nuclear power plant) to Earth.
A century-old concept
The idea of wireless energy is not a recent one. As early as 1901, Nikola Tesla was already imagining a system for transmitting electricity via the Earth’s ionosphere. His project, too ambitious for the time, never came to fruition and probably hastened the ruin of the inventor, who firmly believed in the benefits of electromagnetism.
It was in the 1960s that concrete experiments were carried out. In 1964, William C. Brown flew a small helicopter powered solely by microwaves. In 1975, with NASA, he succeeded in transmitting 30 kilowatts over 1.6 kilometers, but with an efficiency of only 50%.
Since then, the miniaturization of components, advances in lasers and computer science, as well as the energy transition have revived interest in this technology.
Possible applications and challenges
Wireless power transmission could be used in many areas:
- Uninterrupted power supply for satellites and drones
- Recharging electric vehicles on the move
- Supplying power to isolated areas without heavy infrastructure
- Replacement of emergency generators with receiving antennas
Systems such as EMROD (New Zealand) and Reach Power (USA) are working on microwave and radio wave transmissions, capable of reaching an efficiency of 95%, with a target of 99%.
However, several challenges remain:
- Energy efficiency: losses must be minimized.
- Safety: guarantee the absence of risks to human health.
- Wave range: certain wavelengths require huge receiving antennas.
An imminent future?
Unlike other innovations that are promised for the Greek calends, wireless energy transmission has already begun to encounter some practical applications and is not yet another pipe dream of a mad scientist. NASA is firmly interested in it and companies such as Powercast and Wi Charge are testing solutions to power smart sensors and shop lighting. Japan, with JAXA, wants to set up a space solar power plant capable of supplying 1 gigawatt by 2030!
