Solar energy System... need Help!!

I had found a solar energy system schematic diagram on this web address. **broken link removed**

I am not good in analog electronic and i was confused with some terms on that circuit.

1. What does it mean by shunt charge-controller circuit?

2. The word 'solar battery' on the schematic diagram, is it refer to normal rechargable battery?

3. I dont understand the phenomenon of deep discharge and overcharge of capacitor. Can somebody tell me more about it? or is there any good articles on net about those phenomenon?

4. is there any difference between load voltage and line voltage?

thanks

1. A shunt controller probably means it regulates the panel's output by shorting the extra power to ground.
2. Probably.
3. A "capacitor" doesn't have these problems, but the storage battery does. Deeply discharging a rechargeable battery damages it, so you want to just shut off the device when the battery voltage drops too much. Overcharging a battery which is already fully charged can be bad, depending on how high the charging current is and the type of rechargeable battery in question.
4. Yes. The exact meaning depends on context though.

Thanks.
May i know the different between line voltage and load voltage?

Line voltage generally refers to the voltage of the power source, in this case the solar array. Load voltage would refer to the voltage delivered to the load, in this case the batteries.

Thanks very much for ur kindly help