Batteries are rated in AH capacity. Appliances are rated in Watts.
To get how long something will run requires a bit of math to do the conversions.
For instance a 200 watt stereo. (We will give a blanket 20% to inefficiency to illustrate the math.) Therefore, our 200 watt stereo in a 80% efficient system would require 240watt hours to run for 1 hour.
Per Ohms Law:
Watts = amps x volts
watt hours = amp hours x volts
At 12 volts then the math would go like this.
240 watt hours = X amp hrs * 12volts
20 amp hours of battery would be required.
My lineup of batteries at www.bdbatteries.com has amp hour ratings on 12v batteries from 33ah (30lbs) all the way up to 255ah (165 lbs).
The small battery, GPL-U1T, would run for roughly 1.5 hours.
The big battery, the GPL-8DL, would run the stereo for over 12 hours.
Solar panels do not hold any power when there is no sunlight, as they require sunlight to generate electricity. However, some solar panel systems may have battery storage to store excess electricity generated during the day for use at night or on cloudy days.
There are no solar car batteries you can buy. You can purchase a solar battery charger and solar panels but not a solar battery that you install in a vehicle.
about 500watts/meters of irradiance
Most pocket calculators run on batteries because it is much more convenient to use in multiple places. However, some older calculators tend to run on solar power.
the sun gives about 15000 kilo calories in one square foot. when it reaches earth it will have the power to glow a 100w bulb.
It can't work without power. (alternate answer) In principle there are a variety of ways to provide a phone with electric power. Of course, the simplest alternative to a battery is to use a land-line which draws current from the wall (I still use one, myself). For a mobile or cell phone, there are other options. You could use a solar power panel (I own a calculator that runs on a small solar panel; calculators don't use a lot of power, they use much less than phones do) or a muscle powered generator that you crank by hand (there exist radios that work by means of a crank). However, if your phone is not built to work that way, it will be difficult to retrofit it to work differently. Tell Apple that you want them to make a solar powered phone for you. But remember, solar power has its limits. You get no solar power at night, for example. A hybrid system, which still uses a battery but which recharges the battery by means of solar power, is more practical.
about 7% od Americans use solar power
The solar output power will be reduced. If you are relying on it and don't have other sources of power this is a problem. You would need to have a large battery for backup, this would also occur at night.
In some parts of the world, there is NO sun (to speak of) for as much as six months! In these areas, solar power is out of the question, unless there is a monstrously large storage system that can hold the energy during the six months of sunlight!
95%
It uses a little extra battery power, but not much.
Irrelevant, solar power is completely useless