It is true that the gadget does not require a wal-mart charger any more, but the mat will require it. So, intead of manufacturers having to ship a wall-mart power supply with each gadget, they will now have to ship it with each mat. The problem remains, you will have to carry the right plugs for your mat power supply when you travel.
The point of wireless charging is that any wireless charging enabled product can be placed onto the mat to charge - there is no need to hunt around or carry around for the right wall-wart to charge each gadget you own. Nor is there any need for gadget manufacturers to ship a wall wart with every product, which is a waste of resources in my opinion, because when your gadget breaks or goes obsolete then so does its wall wart. The Qi initiative was to get us a standard way of wireless charging, but this is looking shakey now there are competing standards. Hoping Qi will win out soon.
I thought the same thing before I talked to the guys at CES that demo'd this with a Tesla Roadster. They said that with an integrated wireless charging system designed into the car, rather than an add-on like they had at CES, they could get 93% efficiency, and their gap distance between the mat and the secondary winding in the car was 4 inches, which is quite reasonable for that application.
7% loss is indeed significant when you're measuring power in kilowatts, but like I said, it might be worth it for the added convenience & safety.
Correct me if I'm wrong, but isn't the efficiency loss for wireless charging pretty sizable? That's irrelevant for charging a phone, but for charging a CAR? Not to mention that it is already difficult to deliver sufficient power to a car to charge it in a reasonable amount of time when wired; charging a car wirelessly makes that problem far worse.
I agree with you that wireless charging of a phone in the car is reasonable, but only for that minority for whom phones don't last through the day. I think the best solution to having a phone that needs to be charged during the day is to get a better phone, swap batteries, or get a case with additional battery capacity built in...
You don't always still have to plug a charger into the wall. You guys are missing an obvious one -- a wireless charging mat built into the center console of your car. Sure it "only" eliminates the need to have to plug a phone charger into the cigarette lighter, and deal with the annoying wire that always seems to interfere with the cup holder.
As for the EV charging mat on the garage floor, I saw that demo at CES 2011. It was cool, and the convenience and safety relative to plugging the car into the wall just might be worth the loss in efficiency.
I have to agree with them. Wireless charging isn't more convenient - it's not like the extra two seconds to plug in your device is a big deal. Having multiple chargers in the locations you need them is cheaper than having multiple charging mats.
A bigger factor is travel. Do you want to carry around a charging mat, along with the power adaptor to plug it into the wall, or just the power adaptor?
Wireless charging is a problem looking for a solution. Perhaps there are certain types of devices where it makes sense (electric toothbrushes as you mention) but for mobile phones and tablets I think it is just a fad popular for bragging rights. Once the "look what my cool new phone can do" factor wears off, few will care about it enough to consider it a "must have" when making purchase decisions.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.