Why Do Most Solar Panels Have 36 Solar Cells?

Most solar panels that supply power to a 12 volt solar system have 36 cells for a simple reason.

Solar cells come in a variety of sizes. Some are 3 inches by 3 inches. Other sizes are 3 by 5, 4 by 4, and 6 by 6. There are some other odd sizes, too, but these are the typical sizes used for producing electricity in homes and cabins.

Solar cells produce DC (direct current) electricity when exposed to sunlight. How this happens is discussed in another article called,"How in the World Can a Little Solar Cell Make Electricity". For this discussion, it's enough to know that each cell in this size range produces about .55 volts. That is, a little more than half a volt.

In off-the-grid solar setups, electricity produced by the cells in a solar panel is stored in batteries. Without this, there would be no electricity for the house or cabin after dark. However, batteries have their limits and can be damaged if over-charged. Therefore, it's important that your solar panels are producing the amount of electricity the batteries can handle.

In a 12-volt system, for example, the batteries can receive up to 17 volts or so on a continual basis without causing them damage, so long as the electricity in them is being used on a daily basis. Some voltage is lost as it travels down the wire to the battery so producing about 19 volts is ideal.

Here's the math... If each cell inside the panel produces.55 volts and we want the panel to produce about 19 volts, we can divide 19 volts by the amount of volts produced by each individual solar cell, .55 volts, and we get 35.5. That means if we have 35.5 solar cells — rounding up to 36 cells — each producing a little more than half a volt, and we string them together properly, we'll get 19.8 volts coming out of our aire acondicionado solar.

36 solar cells x.55 volts = 19.8 volts.

As I said before, a little bit of that voltage will be lost as it travels down the wire to the batteries. The voltage will be reduced to about 16 volts by the time it gets there. This is still enough to push the electricity into the battery for use now or later.

And THAT'S why most solar panels have 36 solar cells.

For more useful information on solar cells, solar panels and renewable energy, click the link below.

Dusty Foster has been living happily off the grid in the Colorado mountains for the past 16 years. Starting his family off with a small used solar system, he has expanded his solar and wind electric capabilities a little each year. Now he's working on doubling his electricity output with solar panels he's making by hand, using recycled materials.