Going Solar-What you need to know

You are all set to do a solar powered project but what kind and how many photovoltaic panels do you buy? The following information might help you decide.

• Solar power systems are made of photovoltaic modules joined together in an array. The output of the system is determined by the output of the modules.
• Solar cells are connected in series to form a module. A modules output is determined by the number and size of cells in the module.

A typical solar power module of this type would usually be used to provide 12 volts DC to power small appliances or electrical devices. An array of modules connected together can generate much of the electricity used by a typical home.

The number and size of cells in a module also help determine what it will be used for. A module with 36 cells producing approximately .5 volts each has a nominal output of 12 volts and producing about 17 volts under standard test conditions.

How to figure Watts per hour

For this exercise lets imagine we are installing a solar panel array using Kyocera modules producing 17 volts at 3.75 amps.

AMPS X VOLTS = WATTS

Since we know our module produces 17 volts and 3.75 amps then 17 times 3.75 equals 63.75 watts. Thus we know that our module would provide us with 510 watt hours of energy in an 8 hour day. (Calculate Watts n.d.)

Some other considerations

To correctly determine your power need when installing solar power arrays or modules there are some other factors to consider. Solar insolation is the average number of sun hours per day for the area of the country you live in. It is measured in kilowatt-hours per square meter per day.

So, if you lived in Greensboro North Carolina, for example, you would look up a weather map showing the yearly average of the approximate daily sunshine and see that Greensborough has average kilowatt-hours per square meter perday of 4.71. This number will aid you in deciding how many modules you would need for your home. (Free Sun Power n.d.)

With the information now at hand you can decide what type and how many photovoltaic modules you would need for your home. You will also have figured the approximate cost of the system.

Bibliography

Calculate Watts. http://www.enviroharvest.ca/calculate_watts.htm.

Free Sun Power. http://www.freesunpower.com/basic_advanced.php.

Inc, Colorado Solar. "Welcome to the Solar Panel Store." The Solar Panel Store. http://www.solarpanelstore.com/.