How close is wireless power technology?

Why can't we send power wirelessly the same way that we send information, the way that you are most likely watching this video? Well, we can. The problem is, it's not such a great idea to have a lot of energy in the air around you. In this video I tell you what the issue is with wireless power transfer, how far along the technology is, and what the most recent scientific developments are.

And finally, the paper about how metamaterials can enhance near-field wireless power transfer is this:

0:00 Intro
0:58 The problem with wireless power
2:18 Near-field wireless power transfer
4:21 Far-field wireless power transfer
12:34 Recent scientific developments
14:32 Sponsor message

[Alorand]

Definitely interested in that video on meta-materials.

[james]

"So, I guess that means they sell a ... NON-existing method of energy transfer." Brilliant!

[vacuumtubesinc]

I built a tuned coil, essentially a form of crystal radio, to power a LCD clock from a local 50kW am broadcast station. It worked fine 15 miles from the station antenna, and required a 3 ft diameter antenna. Impractical for lots of reasons, but I thought it was pretty cool that it worked at all.

[tenpiualto]

Sabine, I love your dry humor, delivered *almost* completely without any indication you're making a joke. The idea about tiny robots flying around to charge your phone, and the catchy name and website you'd need to become rich with it had me literally laughing out loud through nearly all of your ensuing spiel for Curiosity Stream. Keep up the good work!

[garygough]

There was a farmer lighting his chicken coop wirelessly, but he was 1/4 mile from a 50, 000 watt AM transmitter, using a 1/4 wave antenna ( apx 125 meters ) to a tuned tank circuit. Unfortunate side effects, a huge notch in the radio stations coverage and a high SWR at the transmitter itself.
Still inventive and it was free energy, for him. Incredibly expensive otherwise.

[finlayfraser]

Sabine, there was a case in the UK some years ago. A man whose house was directly under an overhead power line set up a large induction coil in his greenhouse, and was able to provide most of the electricity his home needed for free. However, the power company was able to detect this relatively small drain on a national wide power grid, and he received a heavy fine in court. I understand that was electromagnetic induction, but it is a good story.

[moosethompson]

Thanks, Sabine, this clarified much I had heard about wireless charging and introduced many things I hadn't.
A similar bit on meta-materials would be very welcome.

[scottlysne]

Sabine, love this subject. I work in a lab doing RF->DC conversion. We're ultimately powering drones carrying a Neutron source and Gamma detectors used in explosives detection. It's a bit more challenging than you may think. We're presently transferring 1kW at a straight line distance of 100m. We need about 15kW. The 50GHz spectrum seems to be the sweet spot for this. Affordable, wireless, directional power is a long way off from my perspective. Keep up the great videos, I may have watched all of them. :).

[HelgeMoulding]

My stepdad built his first electronics project in the 50s, a crystal AM receiver that didn't require batteries. It used the energy of the AM signal to power the circuit and a tiny earplug for listening.

[dillbourne]

Sabine manages to discuss the modern state of wireless energy without bringing up Nicola Tesla once. Legendary.

[DJ_Force]

Totally love the dry humor. Actually laughed outload at "...like alarm clocks, and other things you don't use". 😄

[telumatramenti]

4:07 Not to mention just how inefficient this method is. So much of the energy is lost to heat, and what's even worse, the heat is negatively impacting battery life of your phone. I used to charge my phone wirelessly but stopped because of how quickly the battery started degrading and needed replacement. Also, if we want to be environmentally friendly, - we need something just a tiny bit more efficient.

[stickplayer]

Yes on metamaterials. Also, a name for the robot insect charger company: Lightning Bugs

[pontiuspilates]

I always love that Sabine carefully debunks a lot of pseudo-science crap that is being spread among consumer technology people.

[urooj]

Ooh it would nice to have a video on metamaterials. I remember the buzz regarding invisibility with metamaterials

[onedaya_martian]

"It may be used for powering alarm clocks or other things you don't use." I died !!
Sabine... brilliant in so many ways.
Waiting now for the crowd funding for the nanobot company carrying batteries to people's devices so that you can become rich and famous !!

[johnh]

It's now been just over 20 years since a passenger aircraft in Scandinavia had to make an emergency landing because almost 200 people were using cell phones on a short morning flight . With all that wireless going on simultaneously on board an Airbus Aircraft, this caused moderate trouble in the aircraft's electronics and therefore that emergency landing occurred . All that electronics sending out all those signals simultaneously was certainly a bad combo for that morning flight . Wireless technology can only go so far with our present technology otherwise there will be moderate interference with electronic devices .

[leif]

"It'll still be hard to dry your hair underwater" 💀💀 delivery was flawless

[CAThompson]

METAMATERIALS VIDEO YES PLEASE SABINE.
See, this is what I need: To grab my smartphone, a drink and some snacks and to sit near a wall charger to top up my pacemaker battery, instead of being sliced open to replace the battery manually every decade or so. Something else to make @MedlifeCrisis redundant.

[ericfleet]

When we desperately need to conserve energy and reduce our carbon footprint, we are looking at technology that will reduce energy efficiency 90% or more...