Calculate the number of solar panels you require to reduce your carbon footprint and increase the return on your investment.
How many solar panels are required for a typical home? How many solar panels do I need for a house with three bedrooms? For a 2000 sq. ft. home, how many solar panels will I need? ft. home? These are all typical queries from prospective solar homeowners.
You’ll need to know your annual electricity usage, the wattage of the solar panels you’re thinking about, and the estimated production ratio of your solar system in order to calculate how many solar panels you’ll need.
By dividing the system size by the production ratio and then once more by the panel wattage, you can determine how many solar panels you’ll need.
This article will demonstrate how to manually calculate the number of panels you’ll need to power your house.
How Much Solar Do I Need to Power My Home?
According to EnergySage, you’ll use a formula with three important factors to determine how many solar panels are required to power a house: annual energy usage, panel wattage, and production ratios. But exactly what does that mean?
Annual Electricity Usage
Finding out how much electricity your entire household uses annually—or your annual electricity usage—is the first step. This figure, expressed in kilowatt-hours (kWh), accounts for all sources of electricity in your house, such as lights, air conditioners, small and large appliances, water heaters, and air purifiers.
The Energy Information Administration (EIA) of the United States estimates that the annual electricity consumption of the typical household is around 11,000 kWh.
Solar Panel Wattage
Although they may appear to be mostly similar, solar panels aren’t exactly made equally, so you must be aware of their wattage when selecting the best solar panels. The panel’s wattage measures how much electricity it emits.
It is safe to assume that 300 watts per panel are the typical range for solar panels, which typically range from 250 to 400 watts.
Production Ratios
A solar panel system’s production ratio, according to EnergySage, is determined by dividing the estimated energy output of a system over time (in kWh) by the actual system size (in W).
You might assume that there would be a 1:1 ratio, meaning that you would get out exactly what you put in. That, however, is not the case because of variations in the amount of sunlight that enters your home.
A 10 kW system will have a production ratio of 1.6 (16/10 = 1.6) if it generates 16 kWh of electricity annually.
In a place like Hawaii, which enjoys long days and consistent sunshine, it’s totally possible to have this type of ratio, whereas cloudy, rainy New England might see an average production ratio of only 1.2
Calculate How Many Solar Panels You Need
Here’s the actual formula, used by EnergySage, that you can use you’re hoping to determine how many solar panels you’ll need:
- Number of panels = system size/production ratio /panel wattage
- Using the numbers we’ve determined so far, we get:
- Number of panels = 11,000 kW / 1.6 / 300 W
For the job, that translates to 20–25 solar panels. The number of solar panels you’ll need to power your home can be calculated using the same formula. You could also take the simpler route and look at your energy bill to figure out what you’ll need. Read More: Solar Panel Size and Weight: A Complete Guide
Factors That Affect How Many Solar Panels You Will Need
Are there any other considerations besides the calculations mentioned above? As it turns out, there are a few additional factors to take into account when deciding how many solar panels to use to power a home.
Solar Panel Output Efficiency
Your solar panels won’t always be able to absorb the sun’s energy at full capacity. Consider the three-day rainstorms that occur in the fall or the heavy snowfalls that fall during the winter and take several days to melt.
It is advised to have approximately 25% more solar panels than you require because during those times you’ll need a buffer in your energy usage.
Hours of Sunlight
Your home’s exposure to sunlight will directly affect how much energy you can generate with solar panels. If you live somewhere where the sun doesn’t shine for long periods of time, you’ll need more solar panels.
The wattage of Your Panels
Most solar panels have wattages that fall between 150 and 350 watts per panel. You will require more panels with lower wattages to produce enough energy for your home.
Of course, that is assuming that you want to use solar energy to completely replace all of your current energy needs. The difference in solar panel wattage may not matter as much if you’re only hoping for a partial conversion.
Cost of Solar Panels
How much money do you intend to spend on solar panels? Make sure you are aware of the appropriate number for your budget before making a purchase.
Solar Panel Size
You must be aware of the standard sizes of solar panels in order to determine how many can be installed on your roof. Residential solar panels with 60 cells have a surface area of 17.62 square feet, while commercial solar panels with 72 cells have a surface area of 21.13 square feet.
To determine how many solar panels can be installed safely, solar panel installation companies will measure the size of your roof.
How Much Do Solar Panels Cost on Average?
High-end solar panels typically cost between $0.65 and $2 per watt. In other words, depending on the location, a typical 6 kW system can cost up to $12,000. This does not include installation fees, which can increase the cost by an additional $5,000 to $10,000.
As a general rule, PV systems are more expensive but require fewer panels in warmer climates, whereas the reverse is true in colder climates.
Thankfully, tax breaks and other incentives can lower the cost of installing solar panels and offer additional savings over their lifespan.
Summary: How Many Panels Do You Need?
You can estimate the ideal number of panels, or at least a reasonable range, for your electricity generation needs by knowing the answers to the questions above.
The next step is for a qualified installer to evaluate the design of your roof, its orientation in relation to the sun, and other elements to determine whether and how you could physically arrange the ideal number of panels on your roof to meet your daily energy production targets.
Solar DIY kits are your best bet if you’re looking for the most affordable solution. By installing the solar array yourself instead of hiring a professional, you could save up to $10,000 (or more)!
FAQs
How Much Will a 6.6 KW Solar System Save Me?
As a rough guide, a 6.6kW solar system can save you up to and over $2,000 a year on your power bills. Of course, you will need to use a lot of energy during the day, up to 30 kWh during the summer, in order to save $500–$600 on a quarterly bill.
Is 600 Watts of Solar Enough?
A campervan’s entire electrical system can be powered entirely by solar energy with a 600w system, year-round. No need to drive or use shore power. Though you’ll always need to monitor usage and battery levels, with a solar system this size, you’ll comfortably have enough power to meet the needs of 4 people.
What Can You Run on 200 Watts of Solar?
Small appliances work best with a 200-watt solar power system. A 200W solar panel can be used to charge a battery to power small appliances. These appliances include coffee makers, laptops, LED lights, LCD TVs, a radio, a mini projector, and a microwave.
Can I Run My House on Solar Only?
Yes, it is absolutely feasible to run a house solely on solar power by combining solar panels with battery storage. Additionally, it is frequently less expensive than using a local utility to purchase electricity.
Without battery storage, you can still use solar panels to use less electricity from the grid through net metering, which will result in no electricity bill. In the event that solar generation is low, you can continue to use grid electricity and only pay for your solar equipment.
