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Define what you mean by "better".

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What makes one wireless power technology better than another?

I think that you would get a very different answer if you asked a tech blogger, versus asking a consumer. Both perspectives are valid in their own right, but I will save the nerdy blogger technology comparison for another time. Right now I want to talk about what matters to a consumer.


Safety is not something a consumer can necessarily perceive, but I argue that it is essential that a consumer be assured that his/her wireless charger is safe. If there is a concern that your device could be increasing your risk of cancer, disease, or could be causing some kind of physiological or biological damage, I believe that would make any other technical point or feature irrelevant.

That is one reason that I feel so comfortable with the Open Dots technology. It simply does not use any electromagnetic fields or any type of radiation whatsoever. There is a 100% guarantee of safety from cancer, disease, physiological or biological damage, or any type of long-term health effect of any kind. It’s that simple.


To charge your phone wirelessly, you have to set it somewhere, so we talk about placement. Placement matters to a consumer because it speaks to convenience.

There are some technologies we hear about that will charge your device while it is in your pocket, and this certainly would win the category on placement. But these technologies have other problems, not the least of which is that they have not been proven to be safe. For certain of them, Witricity for example, I have shown that they do not meet safety standards, but I will save that for another post.

Of the remaining technologies, you need to set your device somewhere. For Qi and Powermat, you need to set your phone on or very near an exact spot. I always found it somewhat ironic that although these technologies sometimes boast they could be invisibly embedded in a kitchen countertop, for example, there would need to be a visible marking of some sort so you would know the exact spot where to place your device in order to charge.

For the A4WP technology, your device can set anywhere within the area of the pad. However, again, safety is a question mark. For A4WP, its ability to accept random placement is due to its electromagnetic field filling a greater region of space by design, and users are in no way shielded from this additional region.

The Open Dots technology allows you to place your device anywhere on the pad.

So in this category, again Open Dots ftw.

Multiple Devices

It is my opinion that one of the greater benefits of wireless charging comes when mom, dad, and kids all place their phones on a single pad. The nightmare of conventional wired charging is over! The nightmare of fighting over outlets and counter space disappears.

For the Qi and PowerMat technologies, the pad needs to have additional “spots” in order to charge more than one phone. In case you don’t know, these technologies charge your phone only if it is placed over a half-dollar-sized small coil inside the pad. If you happen to have a pad with only one “spot”, you will need to get a second or third pad for more devices. Not only is this costly, but it tends toward the problems with old-style wired charging – that is, fighting over outlets and counter space.

The A4WP technology allows more than one device, but things aren’t so simple. As the number of devices increases, so does the power, and thus the fields in the region become larger to accommodate. The safety question mark becomes an even bigger concern. Again, if you can’t be sure of the safety, does anything else really matter?

An Open Dots pad allows you to charge as many phones as will fit on its surface. That feature is inherently built into every Open Dots pad.

High Power

There is a lot of talk about charging cell phones. That is appropriate, because there are so many in use. Up to now cell phones require up to about 10 Watts of power for charging. But cell phones are not the only devices that can benefit from wireless charging, and many devices require much more than 10 Watts.

Devices that require more than 10 Watts to charge or operate are: power tool batteries, notebook and laptop computers, and heated coffee cups to name a few. We are now even seeing rapid-charge cell phones that require much more than 10 Watts to charge.


Heated Coffee Cup!

As wireless power matures, it will become clear that the applications go far beyond charging cell phones.

Talking about higher power devices immediately rules out some of the technologies. And with all but one of those that are still in the game, the question about safety gets a little more pressing. This is because in order to provide more power using induction, that is, using electromagnetic fields, more field strength is required. So if there was any question of human safety for low power systems, there is even more of a question for high power versions.

Again, the Open Dots technology rides to the rescue. The Open Dots technology can power devices up to 160 Watts without the slightest radiation or electromagnetic fields.

Power Diversity

This seems to be somewhat subtle, but it is actually not subtle at all for users. Power diversity refers to the ability of a low power device and a high power device to share the same pad.

Although this seems like a no-brainer, actually the inductive technologies struggle with this. In order for induction to work effectively at high power, the coils and parameters that are used are necessarily different than those used for low power. Thus, if your inductive pad has a high power “spot”, your low power phone can’t charge on it. As a consumer, this means that you have to think about how many “spots” you need for low power, and how many “spots” you need for high power, because you can’t put low power devices on high power “spots”, and you can’t put high power devices on low power “spots”.

The Open Dots technology has this covered. You can be charging a laptop at 65 Watts, with your Bluetooth headset and your phone also sharing the same pad.


All Devices Welcome on an Open Dots pad!

Again, when it matters to the consumer, the Open Dots technology delivers.


Ideally you want all the power that comes out of the wall socket to end up in your device. Otherwise you are wasting electricity. This is known as efficiency.

You may not know it but there are people working very hard to make sure your products are energy efficient. These people set standards, such as Energy Star, so that manufacturers take care to make efficient products.

We start right away with a problem: Inductive chargers are inherently lossy. In other words, some of the power that comes out of the wall socket does not get into your phone. Some of it is lost in heat and radiation in the process of conversion back and forth between electricity and electromagnetic fields.

In contrast, the Open Dots technology does not convert electricity into electromagnetic fields and then back again. Instead the Open Dots technology makes a direct connection between the pad and the device, much like a light switch. The efficiency of a light switch is so good, we rarely talk about it. It is near 100%. Likewise the wireless transfer power is nearly 100% efficient with Open Dots.


I argue that cost matters to consumers. (I like to bet on the sure thing!) I will make this short and sweet.

Right off the bat, we see that the inductive technologies are relatively complex, and this cost must be ultimately paid for by consumers in the form of higher prices.

Further, all but one technology is positioned to make its creators rich off of its proliferation. They are set up so that royalties are paid each time a product is sold. Of course this royalty is buried in the cost of the product, but consumers pay it nevertheless.

Again, Open Dots is the leader of the pack. Its simple principle of operation translates into lower cost for the consumer. In addition, Open Dots is the world’s first and only open wireless power technology. What this means is that it is the only wireless power technology that does not expect the consumers to pay a royalty to its creators.

The Winner

I just listed 6 points that are tangible and noticeable to consumers of wireless power products. These are the things that really matter as far as using these products every day in every day life.

The Open Dots technology was the hands-down winner across the board. I hope now you can appreciate why automakers chose this technology in their cars. I also hope you see why we are so proud to offer these products on our website to support automakers and consumers of wireless power alike.

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