Roof solar panel installation is a noble idea if you want to lower your power bill. However, the amount of power generated by the solar panels depends on the number of panels installed on your roof and the direction they are facing.
So, what is the best direction for solar panels? The best direction for solar panels is true south, with a tilt between 30 and 45 degrees, as it will generate the best energy production. If you live north of the Equator, the best direction for your solar panels is south. At the same time, those in the southern hemisphere should position their solar panels with a northern-facing orientation for maximum results.
Nevertheless, many variables come into play when it comes to the direction of the solar panels. Depending on your roof, you should study and analyze the right location for your solar panels.
Read on to find out more about optimizing your solar panels’ sun exposure for optimal saving.
Are you interested in exploring how much you can save on your Electric Bill With Solar Panels? Here is an article I encourage you to read.
What Direction Is Most Efficient For Solar Panels?
The most efficient direction for solar panels is true south. South-west and south-east direction are highly efficient; however, an east- or west-facing roof will generate approximately 15% less efficiency than a south-facing roof. By positioning your solar panels south, you will achieve the highest electric bill savings and the quickest payback duration than when facing any other direction.
However, the ideal direction also depends on your roof’s inclination, position, and orientation towards the sun.
What is your solar panel installation goal? Knowing your goal will also help you determine the best direction to install your panels. Consider the table below for the best solar panel orientations:
|Taking advantage of net metering
|Maximizing solar energy output
|Minimizing the effects of high time of use
|South and Southwest
|Reducing grid reliance/pairing with battery
So, in which direction for solar panels will generate maximum energy? The common understanding among many experts indicates that the south-facing solar panels are the most efficient for many homeowners.
Watch the video below to learn more about the key factors that influence your roof’s suitability for solar panels.
Understanding The Solar Panel Positioning
Solar panels facing south will maximize output- If you live in the United States, you are in the Northern Hemisphere, and solar panels are more efficient in producing electricity when they face south. Why?
Throughout the year, the sun is averagely shining directly above the Equator. This means that your house is north of the Equator. You will maximize sunlight exposure if your solar panels face the south.
The whole mainland US lies on the Tropical cancer, which is 23.4°N latitude, meaning all year round, the sun is on the southern half. Therefore, south-facing solar panels will absorb sun rays throughout the year.
South-facing solar panels are ideal for homes with net metering- Are you living in a location with full retail (1:1) net metering? Install your solar panels facing south. Here is why you should do that.
Where 1:1 net metering is implemented, a homeowner’s priority is to achieve the desired level of solar output regardless of when the power is generated.
We have established that south-facing solar panels generate the most overall power. However, they are optimal during midday when the sun is overhead. But at midday, your consumption is at its lowest, so your solar panels will produce lots of surplus power.
With net metering, surplus power is good because you can supply the electric grid with that excess power for bill credits at a retail value.
It does not really matter when solar power is produced for people living in areas with 1:1 net metering. You want an installation that produces 100% electricity at minimum cost. And the south-facing solar panels are your best bet.
Homeowners with a battery system to store power for a rainy or cloudy day aim to produce as much as possible throughout the day. South-facing panels provide enough power for your daytime needs and generate surpluses to charge the battery.
After the batteries are fully charged, they can be used to supplement your power needs during peak times or grid outages. Solar panels facing south and a battery system can significantly reduce your power bills. This also means you will reduce your reliance on the grid or even completely go off the grid.
Solar panels facing south or southwest are good for Time of Use rates (TOU)- If you live in an area with TOU billing, you will likely accrue high electricity bills later in the day (peak rate). This often begins from 4 pm onwards when most people are off work.
Since electricity from the grid is expensive at these times, you need your solar panels to come to your rescue. Light from the setting sun will hit the southwest-facing solar panels, thus producing more power in the evening when you need it the most.
Nevertheless, you will trade the overall solar power generation throughout the day.
Since you want to reduce costs, you will assess how high the peak rates are from off-peak rates. If the difference is double, you can face your solar panels slightly west of south. But if the difference is triple, face your panels southwest.
You might also enjoy reading: How Much Does It Cost To Install Solar Panel? (This much!)
To What Extent Does The Direction Of Solar Panels Affect Output?
In the United States, your solar panels should face true south for maximum power output because the sun is always in the northern hemisphere’s southern half of the sky. Facing south signifies the most direct sunlight exposure.
If you shift the direction, you will notice a fall in the solar panels’ energy generation. Take a look at the approximation in the table below:
|Loss of energy output
As you can see from the table above, solar panels facing southeast or southwest will generate 8% less power than a south-facing panel on the roof. And panels mounted on the east or west roof will generate 15% less energy than those facing true south.
If your panels are facing north- away from the sun- they will produce approximately 30% less output than south-facing panels. In extreme cases, they could produce 60% less energy.
Why The Difference?
The extent to which solar panel loses energy output depends on three things:
- Distance from the south– The higher the degree of deviation from the south, the greater the loss of energy output. A turn to the north will experience the biggest drop, while a turn to the southwest has the smallest drop.
- The latitude– how far north your home is: If your home is further north, you will experience a bigger loss in energy production. For example, solar panels for homes in Seattle, WA, will experience a larger energy drop in a non-south orientation than those in Miami, Florida.
- Your roof’s pitch– the angle you have installed the solar panels: The general rule is that steeper roofs result in a larger output drop for solar panels not facing south.
What If My Roof Is Facing a Different Direction?
Since south-facing panels produce maximum energy output, it can complicate matters if your roof is not facing this direction. However, this should not scare you because not all homeowners have roofs facing south.
These homeowners have installed solar panels and are saving huge on electricity bills.
But how can you install solar panels with roofs that do not face south? Consider some workarounds to help you get the most out of your solar panels.
1- Install More Solar Panels On Your Roof
Increasing the number of solar panels will compensate for limited access to sunlight. You are probably scared of additional costs.
However, the cost of the panels often contributes only a small portion of the total installation cost. You can add a few panels without blowing your budget too much. Most homeowners choose this option with a non-south-facing roof.
2- Install a Ground Solar Array
You can also opt for ground-mounted solar power systems in the yard. It is a better option than erecting racks on the roof or mounting the panels on the wall because it is less expensive. But you will need a large yard space.
The ground-mounted solar system is also easy to maintain. They are on the ground, unlike rooftop panels that require climbing to brush off leaves or snow in the panel.
Furthermore, you can work well with solar panel axis tracking systems to enhance the output of your ground-mounted panels.
3- Use Solar Panel Trackers
If you have extra money, you can spend it on solar panel tracking systems. A tracking system ensures your solar panels are constantly exposed to the sun during the day and all seasons.
Axis trackers are even better at generating electricity using a similar space as a fixed system. However, it is worth noting that solar trackers are expensive, with some costing over $20,000.
What Is The Best Angle For Solar Panels?
The best angle for solar panels is between 30 degrees and 45 degrees. For most U.S. property owners, the best angle for a solar panel installation is near or equal to the latitude of your house (on a south-facing roof), between 30 degrees and 45 degrees.
Besides choosing the right direction when installing your solar panels, you should also pay attention to the installation angle. The general rule for solar panel angles is to tilt them at an angle similar to the geographical latitude.
For example, if your house is at 30 degrees latitude, you should set your panels at that angle. The correct angle will ensure the sun hits the panels perpendicularly, thus promoting optimal solar production. High solar power production means you are saving on electricity bills.
You also want to evaluate how weather patterns in your area affect solar panels. For instance, if you live in a region plagued with heavy snowfall, you can enhance the efficacy of your systems by tilting the panels at an acute angle. This will help reduce snow and other debris from building up on your panels.
If you live in the United States, setting up your solar panels on the roof facing south is advisable. South-facing solar panels have longer access to sunlight which increases energy production.
However, if your roof is not facing south, you can install more panels or use ground-mounted systems to optimize solar energy production.