How Much Solar Power Do I Need?

In order to determine how many solar panels you need to meet your family’s energy requirements, you’re going to have to do some calculations. Keep in mind that different panels will offer different outputs, but the average solar panel can produce 10 watts of energy per square foot in ideal conditions. That’s about 1 kilowatt-hour (kWh) per 100 square feet.

How Much Solar Power Do I Need?

The number of solar panels you need will depend on several factors. The most important element to consider is, of course, your family’s energy consumption. The simplest way to determine how many kilowatts of energy you need to produce through solar power is to look at your electric bill. Your bill might tell you what your annual average is or it might just give you a monthly average. Either way, you want to find out what your daily usage is. If you are given a monthly average, divide it by 30 – if you are given an annual average, divide it by 365. Once you have your daily average, multiply it by 0.25 and add that to your total. Solar panels don’t always operate at maximum efficiency, so you’ll want to give yourself a 25% cushion.

Another factor you’ll need to consider is how much usable sunlight you get in your area. There are online calculators you can use to plug in your location to determine the average number of daily peak sunlight hours you can expect. Divide your daily energy requirements (in kWh) by the number of peak sunlight hours per day to find out how much energy your solar panels need to produce per hour. Then, multiply that number by 1,000 to convert it from kilowatt hours into watts.

How Many Solar Panels Will Meet My Needs?

Now that you know how much energy you need to produce, you can do some simple math to find out how many solar panels it will take to meet those needs. Keep in mind that the quality of your solar panels will affect their capacity to produce energy, and the amount and quality of sunlight the panels receive will change their actual output. Most solar panels for residential installations range from 150 watts to 345 watts per panel. So, decide which kind of solar panels you are going to use (your options may be limited depending on whether you choose to buy your own or lease from a company) and then divide your hourly energy needs by the wattage of your solar panels to find out how many you need.

These calculations will give you a good idea how many solar panels you will need to meet your home’s energy requirements. To determine how much things like the architecture and slant of your roof will impact your solar power generation, talk to a professional installer or solar consultant.