Reddit AMA recap: Long-Range Wireless Power

27
Feb. 2019

long distance wireless powerWi-Charge AMA Link

Our Ori Mor and Yuval Boger recently hosted a Reddit “Ask Me Anything” (AMA) session in the r/home automation subreddit. The AMA covered a number of topics around the wireless charging landscape, the pros and cons of long-range wireless charging and the different use cases that could benefit from such innovation.

You can find the highlights from the AMA below, or you can read the full thread on the subreddit here. If you still have questions that have not been answered in this AMA or on our FAQ, feel free to reach out to here

How long until the Wi-Charge is available to the public?

We expect that the first consumer products incorporating Wi-Charge technology will be shipping to customers within the next year.

Is the 1 Watt per module still in the proof of concept stage?

There are numerous applications today in which 1W is plenty of power for smart home devices and smartphones. Consider a device with 4 AA batteries that you’re willing to replace every 6 months. This works out to approximately 1 mW of average power. Wi-Charge can deliver hundreds of more power continuously.

This means that, beyond not having to replace batteries, you can add features to devices that you could not before, such as adding a camera to a smart lock, having a cordless smart speaker and installing indoor security cameras with streaming video.

Requiring line of sight seems challenging in a typical household environment. Is the thought behind this that there would be many transmitters in strategic places around a home?

One could have multiple transmitters, just like there may be several Wi-Fi repeaters or multiple access points in a larger house. Imagine these transmitters as part of a light fixture, making it easy to install. Regarding the line of sight, this is the only way we are aware of to deliver meaningful power, at a distance, efficiently and within consumer safety limits.

What is the efficiency of the laser to the panel?

The efficiency is 100%, as all power leaving the transmitter reaches the receiver (panel) unit. Light can travel long distances without the beam becoming meaningfully wider. That’s why 100% of the beam can still hit a small receiver even at a distance.

What sizes are the current panels? Do you see the panels changing over time?

The current cells are not very large – they are only about the size of a thumb. We designed it to be small enough so that it can be easily integrated into a phone, home security sensor or another device.

How safe and reliable is Wi-Charge, especially when using such powerful lasers?

Our product is rated Class I, and we were approved worldwide for safety performance. Wi-Charge technology was developed under the constraint of being a class I product, which means “safe under all conditions.” We spent a lot of time and engineering to come up with a solution that would meet all safety regulations.

Can you deliver 1W continuously underclass I?

Yes. This technology was tested and approved by the FDA and other internationally accredited safety labs. Keep in mind that when we say 1W, we are referring to 1W that is truly available for the client device.

Can the light energy from the panels reach any people or things?

Since almost 100% of the light energy reaches the panel, this means that 0% of the light reaches people, pets, plants or objects that do not wish to receive unintended energy. The panel itself is more efficient than a typical solar panel.

What has industry adoption been like?

Industry adoption has been outstanding. We receive over 100 incoming partnership requests each month, most likely because so many people realize that this is an important problem to solve. Several companies are evaluating and building prototypes using this technology, and some companies like Alarm.com and Schlage have even done public demos.

What are some use cases of this technology?

With this technology, we are able to charge a phone without a pad or wire, deliver power to home security devices without requiring battery replacements, make wireless light fixtures, have digital signage and point-of-sale products, deliver plenty of power to AR/VR devices so that they don’t need a battery pack, enable surround speakers and power smart locks and indoor security cameras. For more on this, please visit our applications section on our website and view our demo videos on YouTube.

How is charging mobile phones and powering wireless speakers without batteries possible using 1W?

The power level that you need to sustain a phone is approximately 0.5W – current phones have approximately a 10 WH battery and have an operating time of about 20 hours. Anytime you are delivering more than 0.5W, you are making a positive contribution to the battery. If the phone is on standby, it consumes less than 0.5W. A wireless speaker would likely have a rechargeable battery as well. This allows you to drive higher-power speakers, assuming they don’t operate 24 hours a day. For instance, if we have a 3W speaker that is used 5 hours a day, you need 15-Watt Hour. If you are providing 1 Watt of charging all day, you are delivering more than that number.

Today’s fast cable charging is necessary because you would want the phone to charge as quickly as possible, as you are giving up the use of your phone when it is charging. If you have ongoing charging throughout the day, charging at a lower wattage than the quick charge is also useful.

What would its role be in regard to home automation? Something like keeping motion detectors and contact sensors powered wirelessly?

You can eliminate battery replacements, install devices that previously needed to be wired without wires or create new devices that have the mobility of battery-operation but the power requirements of wired sensors. Additionally, you can also turn existing wired devices into wireless ones. For instance, at CES we showed how we turn an Amazon Echo or Google Home Mini smart speaker into wireless devices (see the bottom of this page).