Why Don't Cell Phones Have Solar Batter Chargers Installed?

Just wondering, as even many calculators have them and I would imagine in an emergency (by day at least) popping off the back cover and letting your cell phone charge up - at least enough to call for help - would be a good thing.
I have seen some devices that are stand-alone solar powered chargers, but I am wondering why they just don’t have one installed on the back of a normal cell phone, so you could set it in the sun and at least get a bit of a battery charge.

Or do cell phones require more power than a solar battery could provide in such a situation?

Calculators have much lower power consumption than cell phones, and a completely different pattern of use (although the usage patterns varies with the user).

A solar powered calculator can function for normal use on a solar cell. For a cell phone it’d be, at most, a possibility in rare emergencies.

The marketing of Cell Phones is such as to make it as cheap as possible with the features people want.

Solar Powered Cellphones exist, (http://www.mobileburn.com/news.jsp?Id=6369) and for just about any cell phone out there you can buy a Solar Charger. But the charging is not as fast as plugging it in and Cell Phones use a lot more power than a calculator so normal ambient light will take a couple hours charge a phone enough for a 20 minute phone call.

Outdoors in direct sunlight, it takes hours to get a full charge with a larger plug in solar panel.

And here’s the biggest reason - A significant portion of the market is turned off by “green” energy and doesn’t trust it for one reason or another. Someone will need to do it first and when it’s been around for a while, they’ll trust it, but until then one company is going to have to be willing to make the gamble. And just because LG and HiTech make Solar Powered Cell Phones doesn’t mean there’s a carrier out there that’s ready to make that gamble yet.

Only a valid observation for the US-market, which still isn’t a driver in cell phone development.

It would be a gamble only if a carrier were to restrict subscribers to a single type of phone. Has any significant carrier ever done that?

I don’t think that’s true, or else calculators wouldn’t be solar powered.

It’s what you first said: Charging in direct sunlight can take a long time, and if you’re indoors or its cloudy, you might as well forget it. Besides, I usually have my phone in my pocket, so it wouldn’t get charged anyway while I’m not using it. However, when I’m at my desk or in my car, I can easily recharge it and its still rather handy. Or, I can plug it in and charge it over night while I’m asleep.

It’s the same reason why we don’t drive electric cars with solar cells on top. They take too much power and can’t recharge quick enough with solar cells.

In fact, a Better Place has plans to have electric car battery switching stations rather than depending upon battery charging. You charge your battery when you’re stopped for long term, but if you’re driving along the highway, you can switch out your battery pack for a charged one in under four minutes.

A cell phone carrier has to buy their phones from the manufacturer in bulk. They order X thousands of phones. The manufacturer then makes X thousands of phones with the carrier’s logo imprinted and a few other bits of specialized hardware and/or software.

When AT&T or Verizon think there’s a large enough market, they’ll let LG know to start making some solar-powered phones for them.

For what it matters, the US is a driving market in the cell phone market, they drive the market for the tried and true technologies in cell phones. It might not be a cutting edge market in the US all the time, but it has it’s moments.

Charging you phone with solar panels is not green. Really it is not. Photovoltaic panels take a lot of energy to make. This energy is paid back over many years of generating electricity when the sun is shining. If you only use the panels for a few hours every few days they are a waste of energy.

The solar cell on a calculator is a different matter. Putting the solar cell on eliminates the need for a battery. A phone uses far too much power to be only solar powered so there are not component savings.

To a sizable carrier, a few thousand phones represents a tiny fraction of their subscribers. So a model needs only niche appeal to be of interest.

So AT&T (for example) says to LG: “A solar-powered phone, eh? Could be interesting. Tell you what: we’ll advertise them and you agree to provide the first couple thousand at a decent price, billing us only for those we sell. If they get a good reputation, we’ll convert this into a significant order.”

OP again.
Thanks for your input, and interesting to learn a lot of this.
However, I meant a solar battery charger just for emergency use, not as the sole source of energy (although that would be cool!).

I am thinking of hikers, or people who just need enough power to call 911 or maybe make a quick call home - the solar charge would work just well enough for someone to make, say, a 5 minute call. It would be just an “emergency” option if your cell died and you really, really needed to get it up and running to make a call for help.

There are tons of third party solar panel chargers for phones. Just google cell phone solar charger. With most new phones coming out being charged over USB you don’t need an adapter for the panels to you phone so third party chargers are easier to do.

Solar charging would only work on a sunny day with the phone in the sun. I think you’d be better off with a crank or some way to generate energy from all the movement a cell phone experiences.

That’s way too unreliable since accidents happen at night, under the cover of trees, on cloudy days, in extreme cold, etc. It’s much easier to just have your phone turned off in your pack and turn it on if you need it. If you need power in the backcountry you bring a dedicated solar charger and/or extra batteries. Not to mention the fact that most backcountry is out of cell phone range to begin with.

Since most people keep them in their pocket, how about a “Faraday Cellphone” type contraption? To many things to go wrong?

I’ve always wondered if cell phones can be powered the same way that self-winding watches can be powered. That is, by the kinetic motions of the users.

Face it: you tend to move around during the course of your day. Why not have a flywheel type setup which uses the motions of your body to run a generator which keeps your phone charged? Granted, phones probably need more juice than a watch, but might it not work?

Sounds impractical - a mobile phone consumes MUCH more power than a watch. The inertial mechanism would probably have to be substantially larger than a typical phone.

I suspect this will happen in another 5-6 years when we have PV coatings that don’t add weight or size to the phone. Right now the weight and size would make this unappealing to mass market.

soon we’ll reach the point where the back of all consumers devices, phones, ipods etc can be a very thin PV layer that adds almost zero weight and you can just place the device upsidedown in the sun to gain some charge… as well as having standard charging methods.

Actually this would be a anti-green add on. Solar panels consume resources and energy to make and have payback periods in years if they are set up in optimal sunlight. A cell phone would normally only last 2 years and a good part of that time in a poor location for the solar panel to work, so very possibly you would never produce enough power from the solar panel to make up for the power that went into manufacturing it.

This is also an issue with the Prius solar panel IMHO, if it’s really green at all, as opposed to putting that panel in a safe non-mobile place (such as home rooftops) that would last longer then the typical life of a car, and can be tilted for optimum light.