At the height of his career, pioneering electrical engineer Nikola Tesla became obsessed with an idea. He theorized that electricity could be transmitted wirelessly through the air over long distances – either through a series of strategically placed towers or by jumping through a system of suspended balloons.
Stuff it wasn’t as planned, and Tesla’s ambitions for a global wireless electricity supply have never been realized. But the theory itself was not refuted: it would simply have required an extraordinary amount of energy, much of which would have been wasted.
Now, a research article suggested that 5G network architects may have unwittingly built what Tesla failed to build at the turn of the 20th century: a “wireless power network” that could be adapted to charge or power small devices embedded in cars, homes, workplaces and factories.
As the 5G depends on a dense network of masts and a powerful series of antennas, it is possible that the same infrastructure, with some adjustments, can transmit energy to small devices. But the transmission will still suffer from the main drawback of Tesla’s towers: high energy waste, which can be difficult to justify given the urgency of the climate crisis.
Decades ago, it was discovered that a strongly focused radio beam it can transmit energy over relatively long distances without using a wire to carry the load. The same technology is now used in 5G Network: state-of-the-art technology to transmit the Internet connection to your phone, via radio waves transmitted from a local antenna.
This 5G technology aims to provide a 1,000-fold capacity increase in the latest generation, 4G, to allow up to a million users to connect per square kilometer – making those moments in search of a signal at music festivals or sporting events a thing of the past.
To support these updates, 5G uses some of the engineering magic, and this magic comes in three parts: very dense networks with many more masts, special antenna technology and the inclusion of millimeter wave (mmWave) transmission alongside more traditional bands.
At the turn of the 20th century, electrical engineer Nikola Tesla started working on a wireless electrical network. In the end it failed. Wallsdesk
The last one, mmWave, opens up much more bandwidth at the cost of shorter transmission distances. To put it in context, most WiFi routers operate in the 2 GHz band. If your router has a 5 GHz option, you’ll notice that movies stream more easily – but you need to be closer to the router for it to work.
Increase the frequency even further (like mmWave, which operates at 30 GHz or more) and you will see even greater improvements in bandwidth – but you need to be closer to the base station to access it. That’s why 5G masts are more densely grouped than 4G masts.
The last magic is to add a lot more antennas – between 128 and 1,024 compared to a much smaller number (only two in some cases) for 4G. Multiple antennas allow masts to form hundreds of pencil-like beams that target specific devices, providing efficient and reliable internet for your phone on the go.
It turns out that these are the same basic ingredients needed to create a wireless electrical network. The increase in network density is particularly important, because it opens up the possibility of using mmWave bands to transmit different radio waves that can carry Internet connection and electricity.
Experimenting with 5G power
O experiments used new types of antenna to facilitate wireless charging. In the lab, the researchers were able to transmit 5G energy over a relatively short distance of just over 2 meters, but they hope that a future version of their device will be able to transmit 6μW (6 millionths of a watt) over a distance of 180 meters .
To put this into context, common Internet of Things (IoT) devices consume 5μW – but only when in its deepest hibernation mode. Obviously, IoT devices will require less and less energy to function, as intelligent algorithms and more efficient electronic components are developed, but 6μW is still a very small amount of energy.
This means that, at least for now, 5G wireless power is unlikely to be practical for charging your phone during the day. But you can charge or connect IoT devices, such as sensors and alarms, which are Expected to become widespread in the future.
In factories, for example, hundreds of IoT sensors are likely to be used to monitor conditions in warehouses, to predict machine failures or to track the movement of parts along a production line. Being able to transmit power directly to these IoT devices will encourage the move to much more efficient manufacturing practices.
But there will be challenges to be overcome before that. To provide wireless power, the 5G masts will consume about 31kW of energy – the equivalent of 10 kettles of water constantly boiling.
While concerns that 5G technology can cause cancer have been widely unmasked by scientists, this amount of energy emanating from the masts can be unsafe. ONE approximate calculation suggests that users need to be kept at least 16 meters away from the masts to comply with safety regulations defined by the US Federal Communications Commission.
That said, this technology is in its infancy. It is certainly possible that future approaches, such as a new antenna with narrower and more targeted beams, can significantly reduce the energy required – and wasted – by each mast.
At the moment, the proposed system is quite reminiscent of the fictional “Wonkavision”In Charlie and Roald Dahl’s chocolate factory, who achieved the feat of radiating confectionery to TVs – but had to use a huge block of chocolate to produce a much smaller one at the other end.
Because it consumes a large amount of energy compared to the energy it will supply to devices, 5G wireless energy is, at the moment, speculative. But if engineers can find more efficient ways to send electricity through the air, it may well be that Nikola Tesla’s dream of wireless power can be realized – more than 100 years since his attempts failed.