How Many Solar Panels are Needed to Power a House?

April 13, 2018


Solar panels are a smart investment for townhome owners in Dallas. It can help you save thousands of dollars on your energy bill and increase the value of your property, should you ever sell it. To reap all the benefits, you need to figure out one crucial detail: the correct number of solar panels needed to power your house.

The first thing that you should learn is that there’s no definite answer to this question. The number of solar panels will depend on your needs and goals. How much energy do you use? How many panels can the surface of your roof hold? What’s the climate like in your area? All these are questions that could influence your needs. You need to sit down and analyze these numbers carefully before making any further investments.


How Much Electricity Will You Consume?

The average American household consumes around 897 kWh per month. That’s 30 kWh daily, or 1.25kW per hour. Of course, you could consume more than the average (or less) depending on how big your house is, how many people live in it, or the type of appliances you have.

The best way to determine how much power you’ll need is to look at your electricity bill and try to determine the average consumption rate. Take that number and divide it by 12 to find out your monthly energy expenditure, or by 365 to reveal your actual daily usage.


Solar Panel Efficiency

It’s vital to note that solar panels don’t always work at maximum efficiency. For example, sometimes you won’t get enough sunlight to generate all the electricity you need to power your household. That’s why experts recommend adding a 25% margin to your daily target to ensure that you won’t be left in the dark. In other words, if your expected daily average electricity consumption is 30kWh, you should target a total output of 37.5kWh for your solar panels.

Solar panels come in great variety, specifically in a wide range of wattages, from 100W to 370W per panel. This variable will also affect the number of panels needed in the end. For a typical American home, you’re going to need 25 conventional 250W solar panels.

Keep in mind that your house’s usable roof surface can also affect your system’s efficiency. If your roof is unusually shaped or if it’s partially shaded, you’re going to need to invest in smaller, high-efficiency panels. On the other hand, if your house is oriented properly and has a wide usable roof surface, then you can settle for cheaper, conventional panels.



If your electrical costs add up to $100 per month, you’re probably going to need around 17 standard solar panels to power your home. But the final answer to the question depends on your geographical location, your panels’ wattage and overall quality, your home’s orientation, and several other factors.

At EcoView Homes you can find numerous townhomes in Dallas that have high-quality solar systems already installed, thus saving yourself from the stress of planning and building a solar system from scratch.