Adding solar panels to your home has numerous benefits and is an investment more individuals are taking each year. Installing solar panels to your home can be a large upfront cost, but over time you can save thousands of dollars on your utility bills — often you start seeing the savings almost immediately. Additionally, solar panels can drastically increase your home’s value and are a large selling factor.
If you have decided to take the plunge and reap the benefits of solar panels, you need to first determine how many solar panels you need for your home. Here are a few steps you must take to help you in this could-be overwhelming process.
1. Determine Your kWh usage.
Kilowatt-hours, or kWh, is simply a measure of energy. Kilowatt-hour is the measure of how much energy you are using at any given time and multiplied by the amount of time it is being used. According to the U.S. Energy Information Administration, in 2015, the average annual electricity consumption for a U.S. residential customer was 10,812 kilowatt-hours (kWh), an average of 901 kWh per month.
To determine how many solar panels you need, you must first find your personal average amount. Gather all your electric bills for the past 12 months, which should state how many kWh was used throughout the month. Add each month’s total kWh usage together and then divide the total by 12. The result will be your average kWh usage. Finally, divide your monthly average by 30 to determine a daily average. This will give you a much more precise starting point.
2. Consider the Sunlight in Your Location
The amount of sunlight you receive in an area will affect how much energy and money you can save from solar panels. If you live in an area that is sunny most of the day, you will need less solar panels than cloudy and rainy areas. You can speak to a professional solar panel installer to better determine how much sunlight you can expect in an area or many maps are available online.
3. What is your Target Goal?
Now that you have your daily kWh average and you know how that more sunlight generally means less solar panels, you need to determine exactly how much energy you wish your solar system to account for. Remember, that your system may not provide 100 percent performance at all times so you will want some cushion room. Whatever the case may be, the higher the percentage your solar panel system accounts for, the more solar panels you will need to invest in.
4. Determine the Type of Panel You Desire
There are many differences in solar panels that affect their performance. A PV solar panel is measured in wattages and is most seen in residential homes. There are multiple types of PV solar panels including monocrystalline panel, polycrystalline silicon and thin-film solar panels. Each type of panel has a different price, durability and performance level.
Monocrystalline silicon panels are a costly option but provide excellent performance and are one of the most efficient PV solar panels available. These solar panels also have the longest life expectancy. Polycrystalline silicon panels are much less costly but they don’t provide the strong performance the monocrystalline silicon panels provide. Thin-film panels are ideal if you need less power and don’t want to pay as much. Unfortunately, this type of solar panel takes up a considerable about of space.
5. Do the Math
When you have all your numbers and know what type of solar panel you desire, then you can start doing the math and figuring how many solar panels you need. Begin by multiplying your daily average by your target performance goal.
For example, if your daily average is 40kWh and you want 75 percent, your equation would look like:
40 x .75 = 30
You must then determine how many kWh the panels you want produce. If one solar panel only produces 1kWh, then you would need 30 solar panels to meet your needs. However, these numbers are a rough estimate and a professional installer can give you an exact estimate and help you better prepare for this large investment.