o begin with, a solar panel, also known as a photovoltaic panel, is one of the components of a solar panel system, together with an inverter, a charge controller, and a battery.
Solar basics. What you should understand before buying a solar panel
If you think about purchasing a solar kit with just one photovoltaic panel, it will most likely not be enough to satisfy your home’s energy needs. You should determine how many panels you need to install, or to put it more correctly, what size of photovoltaic system you should have. Now, let’s move on to the concept of a solar panel calculator, a helpful tool for those willing to go solar.
Calculate the amount of electricity you usually use per month
A solar power usage calculator is based on a formula with several components. The first one is your home’s electricity needs. In fact, to find out how much electricity your home requires, you don’t have to do the calc yourself. You can simply check your past utility bills. What you should look for is called kilowatt-hours (kWh) consumption. Usually, it is stated at the bottom of your bill.
Keep in mind that your energy usage differs from season to season. How can you get the best average estimate of your solar electricity needs? Determine your yearly energy consumption. Just find all of your energy bills from the previous year, add monthly kWh totals together, and divide by 12. Such an estimate will be more accurate than taking a value from one random electric bill.
Do a manual calc of your energy consumption
You may desire or need to manually perform a calc on your kWh consumption. A kWh actually means the amount of energy you use by keeping a 1,000-watt appliance running for one hour. To do a calc of your home’s daily kWh, multiply the power of your appliances in kW by the hours you use them per day. For example, your TV consumes 200 W per hour, that is, 0.2 kW. Let’s say you have it on for 2 hours a day, so a quick calc says the daily consumption would be 0.4 kWh. Run this easy calc for all your main appliances and sum them up. Then multiply the result by 30 to determine your home’s monthly electricity needs.
Calculate how much power solar panels can generate in your location
The second calc to perform is the amount of sunlight in your area. This parameter is most commonly called “peak sun hours.” If you have to define your daily solar hours, the easiest way is to search for a solar energy calculator that shows the number of peak sun hours or a solar map of your region. To determine how many peak sun hours you have per month, run a simple calc and multiply your area’s peak sun hours by 30. On average, the U.S. receives 4-5 peak sun hours daily or 120-150 hours per month.
Do a peak sun hours calc
You may want to know how to do a calc of peak sun hours instead of looking for a ballpark estimate for your location. To perform this easy calc on the amount of sunlight your photovoltaic array will receive, buy an insolation meter. Place the meter in direct sunlight; this device will help you learn everything about temperature, solar energy supply, and current light intensity.
Run a calc on the size of the solar system you need
To define the size of your solar panel system, you can always search for a solar sizing calculator; there are lots of them available on the Internet. A typical solar power calculator is based on a simple formula. Instead of googling for a solar panel sizing calculator, you can efficiently perform a manual calc to determine the size of a solar system you need. And this is how you can do it:
Divide your monthly kWh usage by your area’s monthly peak sun hours to find the panel system size you need in kW. The formula in a solar sizing calculator would look something like this:
886 kWh consumed / 130 monthly peak sun hours = 6.81 kW of solar (7 kW size solar system)
A quick calc to find out how many solar panels you should buy
A final step would be to do a calc on how many photovoltaic panels you need. In order to figure out the necessary number of panels in your solar system, take the size of the system in watts and divide it by the power output rating (wattage) of the panels you want to install. The wattage of most residential modules ranges from 250 to 400 W. For our calc, let’s take 350-watt panels:
6.81 kW x 1,000 = 6,810 watts; 6,810 watts / 350-watt panel = 20 panels
Do a calc to determine the price of your solar system
Once you have performed a calc of the size of the system you need, you can find out the prices. Your calc must consider the Investment Tax Credit (ITC), which currently means reimbursing 30% of the initial cost. For instance, the price of a 7 kW system is about $21,000; after the ITC, it will drop to $14,700. The price of your system could be even lower, depending on what other incentives are available in your area. Do the calc yourself, or use a solar system calculator to identify upfront costs.
A rough calc of your solar savings
Would you like to run a calc to determine how much your solar system can save you can how long it will take for your photovoltaic modules to pay for themselves? This task is not easy, as many factors should be considered, like the initial PV panel cost, all the incentives, the size of the system, your average electric bill, feed-in tariffs (fixed electricity prices paid to solar producers), etc. So, it is recommended to use a solar system calculator designed for this purpose.
If you don’t want to do a calc yourself, you need a solar panel calculator
If you don’t feel like performing an extensive calc on your solar system size or savings, you can always find plenty of resources with a solar energy system calculator. For example, you can start with the Google Project Sunroof1, a solar panel calculator from Google that helps you identify your solar system savings potential. This tool will run a calc for you - all you need to do is enter your home address.