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Friday, April 6, 2018

Myant Responds to Questions Over Dropping Energous

Yesterday I wrote a post indicating that Myant, a "hi-tech clothing company", looked to have dropped Energous wireless charging from their upcoming Fitbit-style-underwear product. Energous made a pretty big deal about the announcement at the end of last year and at CES this January, so it was an equally big deal to see that disappear. Today on Twitter, Alexandros Roussos responded with a comment straight from Myant on this:

First of all, thanks to Alexandros for getting this information straight from the company, there's a treasure trove of information just in those few lines. I have not confirmed this myself, and in the absence of an official statement from Myant, I'm going to take this statement as accurate, should that change or Myant clarify, I'll update accordingly.

Efficiency - Valid Excuse or Covering for Poor Performance?
First thing to note is a confirmation they've dropped the contact wireless charging. That's an "ouch" for Energous. Second is that the reason given is "charging efficiency" - which is a bizarre reason to give. Battery life is around 6 days, and likely around 0.5 Wh capacity, which means around 30 Wh per year, or ~0.4 cents per year of electricity at the average price of 12c/kWh at 100% efficiency. That means 4 cents per year at 10% efficiency, and 40 cents per year at 1% efficiency, for a product that's a few hundred dollars. This is not a reasonable excuse based on efficiency, so maybe they mean charge rate?

How long is someone prepared to wait for charging such a device? Well a Fitbit is around an hour, give or take, so it shouldn't be much more than that every 6 days. Energous claimed around 5 Watts or more charging for the contact system, which would easily charge a device like this in less than an hour. Does WattUp charge at lower rates than this for smaller devices? If someone had to wait 10+ hours for the charging, that would be a good reason to have to have 2 devices (Interestingly in their old package Myant included two trackers, while in the current package it looks like they sell only one. "Use two modules interchangeably for the full 24/7 experience" they say.) A slow charge rate would definitely make it questionable as a consumer product, and I think this is more likely what they mean by "charging efficiency".

It seems to me with this statement that Myant have confirmed that the Energous mini WattUp is not a viable solution for mobile electronics - the core market it's touted as being designed for. That's pretty damning for any product.

Incompatibility - Despite Energous PR Claims Otherwise
One of the very interesting things is that Myant claim that they want to "bring a product compatible with distant charging" which is ridiculous as that was touted as an an inbuilt major feature with the mini WattUp - use for contact charging now, then move to the at-distance charging with the same device in future. In-built future proofing! To quote from Energous' own press release:

"All WattUp-enabled products will support seamless transitioning from charging via Miniature WattUp transmitters, to future stationary in-room transmitters that will offer wire-free charging with mobility at a distance. The result will be a complete wireless charging eco-system."

Has that compatibility been broken? I do wonder if the recent change to 913 MHz for the mid-field system killed any hope of compatibility. (Yes, I know, I'm saying that a unavailable product is now incompatible with another product I'm saying will never be released, I get how ridiculous this is).

Have Myant inadvertently confirmed that the "WattUp eco-system compatibility" does not exist?

At Distance Charging Convenience
The last statement of the charging convenience of "at distance" is ridiculous. If the contact method is inefficient, by definition the at-distance method will be far worse - that's both basic physics and common sense. You won't lose "some" efficiency, you'll lose a lotEnergous' own numbers for their mid field system shows charge rates between 30 mW and around 100mW, so between 5 and 16 hours to charge, while standing in a small region around 50 centimeters on each side, always facing the transmitter. Yes, that's practical...

Maybe it's for just throwing on the nightstand and charging at-distance that way while you sleep - in that case it's no more convenient than contact charging, but a lot more inefficient!

Confirmation of Impracticality?
The response from Myant is welcome, to me it confirms that the WattUp has been dropped from the "flagship" Energous named customer, there is no replacement, that the contact based WattUp system is likely too inefficient (slow?) for most consumer electronics, and that the promoted inter-system compatibility does not exist. A few lines from Myant, and it says a lot to me about Energous' product overall.

A few minutes after posting, Alexandros made the following statement on Twitter, that there was some paraphrasing in his response. You should take that into account when reading this post, however I think the main points of the post still stand.

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