What Size Solar Panel Will Run a Window Air Conditioner?

Consider Your Location

• The effectiveness of solar panels in homes depends on a variety of factors. This includes what part of the country you live in and the type of landscaping in your area, such as mountains or tall trees. Other factors that determine how effective the solar panels are is the season, time of day and weather conditions in your town. For instance, if you live in a hot Florida climate with only sparse, low vegetation surrounding your house, the likelihood of a solar panel supplying the necessary energy for a window air conditioner is high.

Determine the Amount of Sunshine

• It is important that you determine how much sunshine your home receives during the time you will require an air conditioner. This enables you to pick the right size solar panel to operate the appliance. Consulting a sun chart or solar radiation map allows you to find out the amount of solar energy typical in your zip code. A less complicated option is to contact the company you want to use to install the solar panel; they have the resources to calculate the correct panel size.

Wattage Use of Appliance

• Determine the wattage of your window air conditioner by looking on the appliance on the power cord, in the owner's manual or the air conditioner box it came in. Write down the approximate number of hours the air conditioner will be in use typically in a day during the warm weather season. In hot climates, this may be 24 hours of each day. Multiply the number of hours by the wattage of the window air conditioner. The sum gives you the total watt hours for each day.

Other Considerations

• Typically, a solar panel operates about three days on a battery. Therefore, multiplying the total watt hours by three tells you how long the solar panel will run the window air conditioner before the battery requires charging. Multiplying this number by two results in the total battery capacity. Solar panel instructions often advise that you do not discharge your battery by more than half before recharging, thus the reason to multiply the sum by two. This ensures the long life of your batteries.

Selecting Solar Panels

• Find out the solar panel wattage times the hours of sunshine in your zip code. Divide the total daily watt hours by this number. This enables you to determine if you need more than one solar panel or a larger size to operate the window air conditioner efficiently.