Here's Exactly How Inefficient Wireless Charging Is (medium.com) 190
News outlet OneZero crunched the numbers on just how inefficient wireless charging is -- and the results are pretty revealing. From the report: On paper, wireless charging sounds appealing. Just drop a phone down on a charger and it will start charging. There's no wear and tear on charging ports, and chargers can even be built into furniture. Not all of the energy that comes out of a wall outlet, however, ends up in a phone's battery. Some of it gets lost in the process as heat. While this is true of all forms of charging to a certain extent, wireless chargers lose a lot of energy compared to cables. They get even less efficient when the coils in the phone aren't aligned properly with the coils in the charging pad, a surprisingly common problem. [...]
To get a sense of how much extra power is lost when using wireless charging versus wired charging in the real world, I tested a Pixel 4 using multiple wireless chargers, as well as the standard charging cable that comes with the phone. I used a high-precision power meter that sits between the charging block and the power outlet to measure power consumption. In my tests, I found that wireless charging used, on average, around 47% more power than a cable. Charging the phone from completely dead to 100% using a cable took an average of 14.26 watt-hours (Wh). Using a wireless charger took, on average, 21.01 Wh. That comes out to slightly more than 47% more energy for the convenience of not plugging in a cable. In other words, the phone had to work harder, generate more heat, and suck up more energy when wirelessly charging to fill the same size battery. [...] The first test with the Yootech pad -- before I figured out how to align the coils properly -- took a whopping 25.62 Wh to charge, or 80% more energy than an average cable charge. Hearing about the hypothetical inefficiencies online was one thing, but here I could see how I'd nearly doubled the amount of power it took to charge my phone by setting it down slightly wrong instead of just plugging in a cable.
To get a sense of how much extra power is lost when using wireless charging versus wired charging in the real world, I tested a Pixel 4 using multiple wireless chargers, as well as the standard charging cable that comes with the phone. I used a high-precision power meter that sits between the charging block and the power outlet to measure power consumption. In my tests, I found that wireless charging used, on average, around 47% more power than a cable. Charging the phone from completely dead to 100% using a cable took an average of 14.26 watt-hours (Wh). Using a wireless charger took, on average, 21.01 Wh. That comes out to slightly more than 47% more energy for the convenience of not plugging in a cable. In other words, the phone had to work harder, generate more heat, and suck up more energy when wirelessly charging to fill the same size battery. [...] The first test with the Yootech pad -- before I figured out how to align the coils properly -- took a whopping 25.62 Wh to charge, or 80% more energy than an average cable charge. Hearing about the hypothetical inefficiencies online was one thing, but here I could see how I'd nearly doubled the amount of power it took to charge my phone by setting it down slightly wrong instead of just plugging in a cable.
Now put a FLIR camera on the devices (Score:5, Interesting)
I've had some wirelessly charged devices get extremely hot during charging. The waster power aside, it can't be good for battery life.
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I've noticed this, too. Even when some sort of mishap has happened where the phone has been left on the charger for hours but somehow the battery hasn't been fully charged, the phone will be hot, nonetheless.
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And there's the general convenience of it. My wife never charger her phone except when it was going to die. Plugging in a cable was too
Auto alignement (Score:4, Interesting)
If I accidentally misaligned the phone on the charger,
I miss Palm/HP's Touchstone wireless charging for the Pre series that used strong magnet to automatically align the wireless charger and the phone.
The phone would jump into perfect alignment when you "throw it on the charger".
my USB port is getting loose.
Advices:
- buy phones that use USB-C, it's a bit stronger mechanically than micro-USB
- buy phones that have the USB port on a separate daughterboard. They're dead simple to repair compared to soldered-on ports.
- consider using a magnetic plug (the kind MagSafe alike where there's a magnetic socket permanently plugged in the port and a simple magnetic cable is quickly attached/detached), they are fucking cheap on aliexpress, some are universal (The same magnetic cable can work with USB-C, Lighting and microUSB connectors).
I tend to emphasize 1 and 2 for my gadgets.
3 is appreciated by my parents due to reduced motor skills at their age.
Plugging in a cable was too annoying and always got in the way when she needed to quickly pick it up to see who messaged her.
Consider:
- using the above-mentioned magnetic plugs. (easier to unplug/replug)
- using a dock (makes message checking even easier).
(I use the later option. Though you have to make sure that the phone is correctly supported by the dock and that there isn't too much mechanical stress on the port)
She had to get a new phone about once every year because the battery would start to crap out.
Ever considered just replacing the battery instead of throwing away an otherwise perfectly working marvel of technology miniaturization?!?
(I've probably change the battery once or twice for each generation of iPhone that my SO bought).
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Everything that I have that has a battery in it, has one of those little magnetic nubs plugged in, and I have a set of cables in my travel kit. Micro-USB, USB-C, Lightning - I no longer care, because they're all the same now. The cable snaps into place and the device does what it's supposed to.
Until USB-C is absolutely ubiquitous, this seems to be the best it's going to get. Now only if you could run Thunderbolt-3 across one of these connectors...
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If I accidentally misaligned the phone on the charger,
Why not make the charging pads with a shallow saddle in them to encourage proper alignment?
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Well, that would require the manufacturer to put even the smallest amount of thought into their products, instead of just rebadging whatever cheap generic dreck is being cranked out by the hundreds of thousands in some Chinese factory somewhere.
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If you follow the application notes correctly, you should get between 70% and 92% efficiency, depending on the size of the coils.
In a cell phone, you'd need a 2" or larger coil to get good efficiency, because of the shape. A cordless toothbrush can get 90% efficiency with a tiny coil, because the receiver coil sets inside the transmitter, due to the shape of the devices. Modern cell phones are not using 2" coils, you don't want the coil overlapping the battery, and there isn't much room. So there is a tiny
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My phone gets warm enough while charging via USB!
Step 1. Go fully renewable and off the grid.
Step 2. Problem solved.
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Bloody polluting redneck. Real men hook up a dynamo to a practice bike and generate their own power.
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I've had some wirelessly charged devices get extremely hot during charging. The waster power aside, it can't be good for battery life.
Where? Temperatures of devices are not consistently applied in the same place. The heat generated during wireless charging is largely due to the coil itself, which is on the phone surface rather than in the battery chemistry.
You want to really overheat your phone, try charging your phone in a car charger. I've on multiple occasions had my phone beep at me and say "Charging stopped due to high temperature". If temperature is a concern I suggest never taking your phone out in the sun.
Also wireless chargers co
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Devices shouldn't get hot. They can communicate with the charger, allowing it to reduce power output if they are warming up too much.
The Qi standard could be a lot better though. It could have included some means to align the transmitter and receiver using magnets, for example.
Is this supposed to be a surprise? (Score:5, Insightful)
If you've taken first-year physics, you've probably read about induction.
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Re:Is this supposed to be a surprise? (Score:5, Insightful)
They're still absolutely bound by first-year physics, though.
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So what distance does the law start to be applicable? Please tell me.
When the 1/r^2 components of the field become large compared the higher order contributions.
Typically this means "many wavelengths away from the source".
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ahhh, to hand out mod pts or to comment.... there are replies below that say inverse square doesn't apply to near field. To them I say go read it again. Inverse square doesn't DOMINATE at near-field, but it definitely APPLIES. And when you only care about power delivery, you can ignore all the other forces at work, even those that DO dominate. The only thing that matters when you are charging is the electric field. And it will obey the inverse square law. Cut the distance in half, square the power.
Re:Is this supposed to be a surprise? (Score:5, Insightful)
I was surprised it was so good. ~60% efficiency. They've come a long way.
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MIT wasn't building consumer electronics.
There's probably a device outside your house right now that's getting pretty close to 100% efficiency with contactless power transfer. It's a pain in the ass to carry in your pocket though.
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If you read any material on the subject, the distance depends on the size of the coils. To get 2 meters distance with good efficiency you need 2+m coils perfectly aligned, or 3+m coils with slightly relaxed alignment requirements.
Cell phones have a tiny coil, the charger has a larger coil, the efficiency isn't expected to be great.
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Re:Is this supposed to be a surprise? (Score:4, Insightful)
But every last one of us got shouted down by idiots who can't or won't understand the facts and just wanted their magical wireless charging of their toys.
Some even believed that you could just have a whole room where so long as your device(s) are in it, they'd get charged. *facepalm*
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Re:Is this supposed to be a surprise? (Score:5, Informative)
High transformer efficiency comes from having the two coils wound around the same iron core so that they are very tightly coupled and all the magnetic field generated by the primary also passes through the secondary.
Wireless charging of phones uses two coils which are several millimeters apart and quite weakly coupled. So only a fraction of the energy put into the primary coil is picked up by the secondary in the phone. I'm surprised they're reaching 50% efficiency.
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I've heard of induction but I'm not sure what you're suggesting here. Induction can be extremely efficient. Even small inefficient transformers are usually better than 85% efficient, and the big ones much more so.
Yeah, but for your examples the coils in question are around the same core and so close as to be practically touching (fractions of a millimeter). A phone on a wireless charger has the coils least 3mm away from each other, which would account for a substantial drop in efficiency (inverse square).
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That was after the fall of Atlantis and the loss of all their sweet, sweet superior technology. When the Atlanteans escaped through the Stargate, while waving goodbye to some drunk Greek fisherman, all they left behind was a few potatoes with copper nails stuck in them, some amber, and a nice silk handkerchief.
A tiny extra cost (Score:5, Insightful)
At my house ($0.27 per kw/hr) this would be about an extra $0.66 per year. Meh.
Sounds like a non-story or perhaps a confirmation that the convenience of wireless charging is worth it.
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Agreed. At over 60% efficiency, wireless charging seems like an ideal solution for "low power" items. Things like cordless toothbrushes, and yes mobile phones.
In term of worrying about heat, the heat losses are not "in the battery", so the battery heating is less of an issue that you would surmise (not that this is zero). Then again, really fast charging does not tend to happen wirelessly, so the battery wear is probably inherently lower.
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Yes, it is insignificant for small batteries. It is something worth considering when people talk about wirelessly charging larger items, like BEVs, though.
Re: A tiny extra cost (Score:2)
Larger items can have larger coils and therefore better efficiency.
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but no, as the summary says, if you don't line them up properly.
so a EV with a wireless charger that's "parked" mostly inside the white parking lines as most seem to be these days, will charge at less than 40%.
For a phone, it works because the charge required is small. For an EV that uses a lot of charging, efficiency matters a lot.
Re:A tiny extra cost (Score:5, Insightful)
Stories like this completely miss the main reason why wireless charging sucks: portability:
And I also need to have a flat surface on which to put the charging pad where the phone won't get bumped enough to prevent it from charging.
At home, wireless charging is no big deal. While traveling, it's a world of hurt. In a typical college dorm room, it's a show-stopper. Wireless charging as an optional way to charge is a great design. Wireless charging as the only means of charging is a terrible, user-hostile design.
Re:A tiny extra cost (Score:5, Insightful)
If I have a phone that charges only wirelessly, I need to bring...
...a type of phone that actually exists? Where is the phone that only charges wirelessly?
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There aren't any, AFAIK, but there have been a lot of rumors suggesting that Apple is considering building one.
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...Where is the phone that only charges wirelessly?
My daughters usb port is broken, does that count?
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Which means she has a phone with a redundant charging mechanism. Holy shit, not sure how you can complain about that! The other alternative is a new phone.
This, in part, is why I spent a bit extra to have wireless charging. The major failures in my last two phones were the charging ports. Most of the time now the phone just gets tossed on the charger and doesn't get plugged in. I'm likely saving a ton of wear and tear on the charging port.
When I travel, I carry a couple of USB chargers and adapters in my ba
Re: A tiny extra cost (Score:2)
The USB ports seem to be FAR more durable now, so I don't worry about it. I think I read that they started using ribbon connectors rather than soldering them to the board because of durability issues.
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My daughters usb port is broken, does that count?
You might want to take her to a doctor, I don't think a USB port should be in there.
Re: A tiny extra cost (Score:3)
And I also need to have a flat surface on which to put the charging pad where the phone won't get bumped enough to prevent it from charging.
You're working very hard to try and find problems, and failing IMHO.
I know of no cellphone that is only able to be charged wirelessly, so your issue is fiction.
And where are you traveling that you can't find a "flat surface"? Where are you staying with no dressers, side tables, or window sills, let alone tables?
The fact that you had to go to such extremes underscores the weakness of your complaints.
Re:A tiny extra cost (Score:5, Insightful)
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I'd really love to see your math on that one.
Re:A tiny extra cost (Score:4, Informative)
Extra $0.67 per year for one person with one device...
USA population 331 million.
Works out to roughly 220 million dollars per year in extra electricity consumption, assuming 1 such inefficient device per citizen.
Sometimes inefficiency can't be avoided, or takes time for inefficient devices to age out of the market and be replaced with newer more efficient ones (eg cars, light bulbs etc), but in this case it's the other way round - the new wireless chargers are less efficient than the old wired chargers.
In general there is a trend towards more efficient devices.
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But how much convenience, or even "coolness", do they create? If it's enough that the average smartphone consumer would value it at over $0.67, then it's a win for society.
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Some minimal noise on the power bill.
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This is true. But as much as I think inefficiency should be avoided we should focus on people who insist on clinging on to traditional lightbulbs and boot bitcoin off the internet.
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Either way keeping them on all the time is an additional cost.
Re:A tiny extra cost (Score:5, Insightful)
Same - you can run a small mobile device at full power 24/7 and it won't noticeably affect your power usage. If it uses 50% more power due to being on wireless charging, it's still a drop in the bucket compared to other power consumption in the average business or household.
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The cost of the electricity is relatively low, but what about the cost of accelerated aging of your phone battery? All that inefficiency ends up as heat; charging batteries at elevated temperatures substantially reduces their lifetime.
Still cheaper than replacing usb cables (Score:5, Insightful)
when the spring clips on them fail. about every 6 months for some of my devices.
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Repeated recharging over micro USB has ruined the micro USB port of a set of headphones I had. What a pain this was.
I hate buying anything of value when it can only be recharged over micro USB.
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Don't have that problem with lightning connectors.
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This. Or worse, replacing the jack in the phone itself. The expenditure of physical products (and charging cables are practically disposable) results in the consumption of significant resources in manufacturing. I guarantee that it costs more energy to manufacture a single USB cable than the inefficiency of wireless charging a device.
Re: Still cheaper than replacing usb cables (Score:2)
Just make the damn phone not so goddamn thin, and put on a proper connector!
Hell, make a phone where I can quickly swap the battery for a charged one, and put the emply one in the charger!
Stupid is no excuse for even more stupid!
Re:Still cheaper than replacing usb cables (Score:4, Insightful)
What kind of cable are you buying?
I had my share of broken micro-USB cables, but unless I step on them, they last for several years. In fact my most used cable (an original Samsung) outlasted my last phone. The other cable that I carry every day in my bag has weakened spring clips indeed, but it is also 4 years old, and it is still usable (doesn't come off unless I tug on it).
Not all cables are created equal. Samsung cables in particular look over-engineered. But considering that the spring clips haven't weakened at all after several years of use, there may be a good reason.
Same thing for the phone side. micro-USB connectors are designed to be robust, however, there has been instances of improperly supported connectors that fail much sooner than they should. Plus, of course, poor quality products.
USB-C is supposed to be more robust so that should be less of a problem. As for lighting, I think the reason why it tends to fail less is mostly because Apple is pretty much the only manufacturer, and considering how much their charge their customers, they don't feel the need to shave fractions of pennies for a lesser product like some micro-USB manufacturers do.
Re: Still cheaper than replacing usb cables (Score:2)
Fun fact: Thinkpad engineers solved that problem a long time ago: Put the connector on a separate board, and connect it to the main one with wires. Now you can wiggle it all you want. The connector, in its rubber fixture, will just wiggle with it. And if it still breaks, replacing is trivial. Solder on some new wires. (Through-hole for easy soldering.) A child can do it. No micro-fracturing of the main board, no need to throw away the device.
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Thinkpad engineers did many things right. Another one is the spill-resistant keyboard. It has built-in channels to drain water away from sensitive components.
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Not so relevant (Score:5, Informative)
I'd nearly doubled the amount of power it took to charge my phone
This is not wrong, but also it is not very relevant. The cited increase in energy, 10Wh, required is the equivalent of running a typical microwave for less than one minute.
Re:Not so relevant (Score:5, Funny)
You heard it here, folks: you can charge your phone in the microwave.
Re:Not so relevant (Score:5, Funny)
IN LESS THAN ONE MINUTE!!!!
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You heard it here, folks: you can charge your phone in the microwave.
They're gonna test that, right? And also putting light inside the battery to see if that helps. They're gonna test that, too?
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You heard it here, folks: you can charge your phone in the microwave.
They're gonna test that, right? And also putting light inside the battery to see if that helps. They're gonna test that, too?
Most semiconductors are capable of this trick.
Re: Not so relevant (Score:2)
Fun fact. Running a standard 600W microwave with an open door at 1m away, is equivalent to having about 500 phones with an active UMTS call tied to a stick, and swinging it around your head at 50 RPM (60 in the US) at 1m distance.
The rotating it around your head is key to it becoming a danger, btw. Otherwise it isn't much.
And all it does, is rotate polar molecules, or twist molecules with polar parts. Which may break proteins, but otherwise just causes heating.
If you don't rotate it, it is merely like the i
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It can be a problem if you're charging wirelessly from another battery powered device. For example with this power bank [banggood.com] or this laptop [techcrunch.com] you'll get fewer recharges than if you used a cable.
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I'd nearly doubled the amount of power it took to charge my phone
This is not wrong, but also it is not very relevant. The cited increase in energy, 10Wh, required is the equivalent of running a typical microwave for less than one minute.
Quite a few people have observed heat as a side-effect of wireless charging.
If you're heating the battery up quite a bit more with every wireless charge, the increased cost will become far more obvious in a world of non-removeable batteries. We already replace our smartphones way to often due to greed (forced obsolescence). How many batteries will die prematurely or far faster because of wireless charging?
Annual costs are... (Score:3)
(21.01Wh - 14.26Wh) = 6.75Wh more to wirelessly charge your phone once.
365 * 6.75Wh/1000 = 2.46 KWh more power used to wirelessly charge your phone all year.
2.46 * $0.32 $/KWH (power rate in the most expensive state in the US) = $0.79 cents more per year, to wirelessly charge your cell phone in Hawaii.
Cellphones are ridiculously low power.
This problem was already solved (Score:2)
There are connectors designed for charging which inherently do not have this problem. Take a look at a drill battery, or a camera with a removable battery, or a wireless phone (not a smartphone), or an RC toy, or some other piece of electronics that don't have a USB connector.
Although if inefficiency is the only problem, we shouldn't be too worried. The electricity lost charging all the cell phones in the world seems probably insignificant. It's probably on order of a light bulb for each person.
Re: This problem was already solved (Score:2)
Exactly. Why don't we have phones where you just
slide out the battery / take off the back cover (that contains the battery), and put it on the charging connector, while we put in the other battery, and have de-facto an *instant* re-charge?
I tell you why. Because some literally mentally ill nutjobs are obsessed with making the phone thinner for no freaking reason and removing all ports for precisely the reason of total control over it, and protection from you.
Oh, and yeah, I think a properly designed electri
In other words, the phone had to work harder (Score:4, Insightful)
>In other words, the phone had to work harder, generate more heat, and suck up more energy when wirelessly charging to fill the same size battery.
In other words, you are clueless? The charger beamed more power. Phone didnt care one bit, _didnt_ generate more heat and _didnt_ suck up more power. If it could suck more power it would be more efficient.
Other factos (Score:4, Interesting)
Everything he said is true, but you need to consider some other factors as well.
Convenience, no more replacing wires when the connector gets bent, and the ease of charging multiple devices come to mind.
Re: Other factos (Score:2)
"Convenience"... like not being able to hold up the pbone to your ear or turn over in your bed while using your phone, because you can't be bothered to design a sturdy connector, or phone that has space for one of the many many that already exist, or for a battery, or for a keyboard, or for a headphone jack.
Lucky that the phone is "smart" for you! --.--
How did you get to be so /insanely/ stupid?
Not a huge difference even in such extreme cases (Score:2)
I will never downgrade from wireless charging unless somehow forced to. I have wireless charging stands at my nightstand, work desk, in my car and will get more of them where needed. Why would anyone use a mat instead? Wireless charging is perfect for phones where the energy bill doesn't make a real difference one way or another and gives the convenience of using the device single-handedly, even when charging or removing from charging. Especially in the car, single handed operation is very important, but it
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Yeah wireless charging has been a god send for us. Once you hit critical mass of about four wireless chargers (3 at home, 1 at office desk) you basically never need to plug in ever again.
Bonus has been that wife who has an iPhone, can no longer steal cables to take to the office, so her phone is always charged at home now, too.
Wireless chargers from good brands (anker, etc) are in the $10-14 range, and they last between phones, so they're a good deal these days.
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Solving marital problems with hipster technology. That's a first.
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Stop using your phone while driving.
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I will never downgrade from wireless charging unless somehow forced to. I have wireless charging stands at my nightstand, work desk, in my car and will get more of them where needed. Why would anyone use a mat instead? Wireless charging is perfect for phones where the energy bill doesn't make a real difference one way or another and gives the convenience of using the device single-handedly, even when charging or removing from charging. Especially in the car, single handed operation is very important, but it's convenient elsewhere as well.
Most jurisdictions have made using phones in hand-held mode illegal in the car, but, personal convenience must triumph
When this is important (Score:2)
As others have pointed out, the annual cost of this inefficiency is less than a dollar, which in terms of both manufacturing energy and monetary cost is less expensive than replacing a single worn out USB cable. So it's a non-story.
However, the area where this is really important is in battery packs. I have two battery packs that have wireless charging built in. This seems pretty awesome at first, that I can just lay my phone on the battery pack to charge it without a cable. However the inefficiency her
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Of course they are net efficient (Score:2)
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How is wireless charging even legal? (Score:3)
Many countries have banned iron core transformer chargers because of efficiency reasons. How can wireless charing devices even be legal in countries that have banned the more efficient but still wasteful iron core chargers?
"whopping"??? (Score:2)
So a misaligned phone took "a whopping 25.62 Wh" to charge? Before efficient light-bulbs I'd keep a 40w bulb on all night; that was 40*12=480Wh per night. Now I use a 6w bulb, for 6*12=72Wh per night. I'm pretty sure the convenience of wireless charging easily makes up for the whopping amount of power it wastes.
Seriously? (Score:2)
On paper, wireless charging sounds appealing. Just drop a phone down on a charger and it will start charging.
In reality it sounds appealing as well.
There's no wear and tear on charging ports, and chargers can even be built into furniture.
Not so sure about building them into furniture, but I find preserving the MicroUSB connector a good thing.
Not all of the energy that comes out of a wall outlet, however, ends up in a phone's battery.
Who cares? Seriously, who cares? If you need absolute efficiency every phone has a microUSB or lightning connector when every watt is precious.
Charging (Score:3)
Of course it's inefficient.
The reason I don't use it is not that... it's that you can't use the damn thing while it's charging.
Get home from work, battery is knackered from working all day, I plug it in, but now I couldn't pick it up and use it comfortably.
Plug it in, I can still use it, and it charges twice as fast (in case of proper USB-C PD, it only needs a small amount of time to charge at all) so I can use it all evening after the time it takes to eat my dinner.
No special pads, no alignment, and I don't know what you guys are doing to your cables but you need to stop - I buy a cable every few years at best and normally because I've lost them or used them for something else. A pack of cables on Amazon is a couple of quid - doesn't even approach the cost of a charging pad or similar a year.
And the charging efficiency does matter, but not in the home. I take my phone camping, travelling... wireless charging means my battery pack provides half as much power and many of the places I go haven't even caught up to USB sockets yet, let alone standardised wireless charging pads.
It's not that it's a bad idea - it's not, we used it for electric toothbrushes for decades already. It's that it's not anywhere near a cure-all for many people's use of their phone. I'm far more likely to be "caught out" somewhere with a low battery, and wireless charging doesn't help there. If anything, you still need to carry cables in those circumstances because the chances of something having a USB port vs the chances of something having Qi charging are far greater.
I charge my phone on planes, abroad, in a tent, on a hike, camping, etc. That means that I carry a battery pack everywhere, and wireless would just cut that pack-time in half. Of an evening, I plug it in (every evening, even if it doesn't need it) because I'm still using it.
I don't even charge it in the car unless I'm travelling lots. Even some basic USB ports can't stop the power dwindling if it's plugged in, the screen is on, the satnav is navigating and it's a long journey. You really don't want to get the other end and find that it's lower on the battery than when you started out.
I don't understand wireless charging, not because it's inefficient (but it is, obviously), but because I just don't get it. You put the phone in a special spot... so just buy a cheap USB charging stand for that spot rather than a charging pad.
The charging takes twice as long. Not everyone has one of those chargers (but everyone has something USB now, so you have to carry a pad around with you?). And when you're away from USB ports and only have a battery pack, you just threw half your power away before you started.
Or what I do... a little shelf designed for a phone with a large hole in it for the cable, so if it rings, you can still pick it up and talk while it's still charging. And a battery pack with a couple of cables (which you'll probably need anyway).
It's also NOT WIRELESS. Just fully retarded. (Score:3)
As you may note, there is a cable coming out of the charging pad.
And you have to keep the phone physicslly close to the pad.
So in essence, all it does, is makes it impossible to hold it up to your ear to make a call, as all it is, is a low quality transformer that comes apart when you even lift it.
This is literally full retard. Like a joke from Idiocracy.
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But hey, with phones getting thinner and thinner, the logical conclusion is to get the thinnest of all: One with de-facto no battery! You already *have* to add some protective cover/case because it's so fragile. Soon you'll have to do it because you'd otherwise cut yourself on the razor-thin phone! ;) (Don't laugh, I am buying a case right now, because I recently cut myself on a broken *glass* *back* side of my phone!)
So why not put all of the battery into the case, and claim yours is the thinnest? Some manufacturer will do it, sooner or later. Phone: 'only' $999. Compatible battery cover: $599. Genius!
At least you won't 'have to' do any thinking or choosing anymore. Imagine that horror from the beforetime! Hey, Siri, who am I?
"You are Apple. Its 328372749th humanoid tentacle, to be exact."
Tragedy of the commons in action (Score:5, Insightful)
See all the comments going "oh, a 47% increase isn't too bad, it's only 2 kWh/year". Multiply that by all the phone users in the US, and you end up with a 500 GWh increase. Not so trivial any more.
Re: (Score:2)
See all the comments going "oh, a 47% increase isn't too bad, it's only 2 kWh/year". Multiply that by all the phone users in the US, and you end up with a 500 GWh increase. Not so trivial any more.
But we have all of that clean coal and nowhere to burn it!
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This is just minor noise in the big picture. If you care about energy saving, this is not the first thing to be concerned about.
No good for power-limited environments (Score:2)
Let's hope wired charging will stay an option, and not be ditched like the 3.5mm audio jack. Wireless charging is no good options in a power-limited environment, for example when charging from a small solar panel on a muti-day hike, or from a bicycle hub dynamo on a day-long ride. Also, a wireless mat would be a bit impractical in a backpack.
I personally liked the USB-less solution on the old waterproof Xperia Acro S: Two metal plates on the side of the telephone (flush with the casing); when inserting in a
Bottom line: We. Don't. Care. (Score:4, Insightful)
A back of the envelope calculation showed the inefficiency of the process long before it was even a reality BUT no matter how much we claim to worry about 'climate change' WE WILL NEVER PRIORITIZE ANYTHING BUT OUR CONVENIENCE. Inefficient use of resources is the cause of 'climate change' and that will continue until there are literally no other options.
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That heat is enough to fry and egg or give first-degree burns...
Just about any heat is if you concentrate it in a small enough volume. Just like just about any heat is effectively zero if you spread it out over a large enough volume.
To put your nonsensical rambling into context, did you know a human gives off 100+ watts? Times 24 hrs and that's more than 2,400 Wh!
If 40 Wh from the charger is enough to cause burns and cook eggs, I bet a person can melt STEEL! I mean, that's 60x more heat than it takes to cook an egg, and I cook an egg at like 300F so that's like 18,000F!
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Or in cold countries, the extra heat generated means slightly less heat that has to be generated by dedicated heating equipment.
Re: (Score:3, Informative)
Yes, but the power factor on the inductive charging is around 0.5, whereas the power factor on your typical single-element heater is 100%.
You can't get "more" out of inefficiencies. No matter how much you take those inefficiencies, an efficient system is better than an inefficient one.
Entropy exists because energy in a system decays. The more efficient your system the slower you introduce entropy into it, but still it increases.
This started as an "exhaustive" study of how inefficient inductive chargers ar