What is the difference photovoltaic solar panels and thermal solar panels?

Charging Baterries through Photovoltaic panels?

• How to calculate or size dimentions of Photovoltaic panels panels for Charging Baterries. Please also direct me to good web pages pertaining to issue. I would prefer practical down to earth answer than just calculations. Thanks

• Answer:

  If u r considering 2 making ur own photovolatic panels, I dont have the info that u r looking 4. However if u want to charge lead acid batteries using photovolatic cells note the following points. Consider the voltage and Ah (Ampere Hour) capacity of the battery. For example 12V 7Ah. Consider purchasing a photovolatic panel which has a rating of at least two to three volts above ur battery voltage. i.e. 15V and a current rating of at least 500mA at bright sunshine. Thumb rule - As current rating of panel increases, the size of the photovolatic panel increases. If a 15V panel is non-standard, then consider connecting two panels of 12V in series and insert a regulator circuit (LM317 is a good choice) in between the panel and the battery. In this case even though the cost is double, it will have a wide input range - from cloudy climate to bright sunshine and u dont have to worry about the battery not being charged.