Can I Run My Home on Solar Power Alone? Net-Zero Vs. Off Grid
Updated: Jan 14, 2022
Can you run your home on solar power alone? It would be easy to say yes and leave it at that. However, the answer is more complicated. You need to address many factors before a quality and a solid answer to that question becomes clear.
The idea of running your home on just solar power is not uncommon. The challenges of doing so can be extreme. While we don't want to "rain on the parade," we do want readers to be aware that there are challenges. Keep reading as we go through those challenges and offer some solutions that can help overcome them.
One of the first choices you would make is deciding if you are going off-grid or aiming for a Net-zero operation.
Off-Grid - You rely solely on the power from the array without backup energy being available from the power company's grid.
Net-Zero - Your arrays design is such that it produces as much energy as you have traditionally used. When more energy is needed, it comes from the power company's grid. The grid acts as a backup energy source.
Is one type of system better than the other? The answer depends on your home, energy usage, and available sunlight. We recommend Net-Zero since you have the ability to obtain power from the local grid. When you are off-grid you are limited to what energy is available through your array, and seasonal variations in sunlight can limit the production of solar energy from your array.
Energy Production Capabilities
The next big issue to tackle is Energy Production Capabilities. To make an informed decision about going solar, you need to understand how much energy your home can produce. This is essentially evaluating how much direct sunlight an array could receive given the location of your home, obstacles, such as trees or buildings, etc.
1 Do You Have Enough Sunlight to Hit Target PV Intake?
Here are some facts to help frame this question.
• There are 1,000 watts in one kilowatt-hour (kWh).
• The average solar panel produces 320 watts per one hour of direct sunlight, which is about 1 /3 of a kWh.
The first question that you need to answer is how much energy it takes to run your home. Generally, we are talking about the amount of energy your household uses each month. There are two ways to approach this:
1. Find the average energy uses across all 12 months
2. Find the month with the highest energy usage and set that as your benchmark.
If you use the average energy usage as your benchmark, then there will be months when you use less energy than produced and months when you use more energy than produced. If you are serious about going off-grid, you have to make sure that your solar array can produce the maximum power your home needs. Otherwise, extra energy would need to come from the grid or potentially a battery backup system.
Understanding the amount of energy your home can produce helps in the decision-making process of going off-grid or going net-zero.
2 How Many Hours of Direct Sunlight Does Your Home Receive?
The second question to ask is how many hours of direct sunlight would my array receive?
That answer is going to vary for each house and across each month. The southern side of most homes receives more direct sunlight than does the northern side. Naturally, you'd want to place the array where it receives the most direct sunlight.
The next step is to ask how many solar panels my array needs to meet my energy requirements. The amount of energy that each panel produces is variable based on the manufacturer. Most solar panels produce 320 watts of power for each one hour of direct sunlight.
Say that your house needs 1,000 kWh of energy each month. In a year, your home uses 12,000 kWh of energy. Since there are 365 days in the year, we can conclude that daily, your home requires 32.88 kWh per day. That's 1,000 kWh x 12 months = 12,000 kWh yearly/365 days= 32.88 -for simplicity, we would say 33 kWh per day.
If each solar panel produces 320 watts of energy for each hour of direct sunlight, how many solar panels would your house need? The answer depends on how many hours of direct sunlight the home receives.
If your home receives four hours of direct sunlight per day, then each solar panel would produce 320 watts x four hours or 1.28 kWh of energy each day. If your home needs 33 kWh of power each day, then 33 kWh / 33 would be 25.8 or 26 panels. These formulas are examples of how to figure out how much energy your home needs. Their answers help you determine if you can go off-grid or if you need to remain tied to the grid.
Can You Power Your Home with Solar Energy?
Again, the question is not a simple, yes. Other factors that impact this answer include whether you plan to stay connected to a grid and whether you plan on installing battery storage. Batteries store the extra energy collected from your array, which means you can use it later. Batteries help supply power to your home when sunlight is not available or when incoming solar radiation is weak. A backup battery storage system is almost essential for off-grid systems. They are also helpful if your goal is to use zero-energy from the power company but still remain connected to the system.
Solar arrays power many homes. Some are off-grid and rely only on the energy their array produces. Some remain connected to their local power grid and use the energy from their array to power their home and then draw on energy from the grid when they need more energy than their array produces. Because the answer is so specific to each property, it is best to talk with an expert who can help customize the solution to fit your home and energy lifestyle.