How do you determine the best solar panel angle, and is it important?

We all learn as children that the sun rises in the east, sets in the west, and is vertical in the sky at noon. This proverb gives the impression that understanding the sun’s motions is simple.

The sun’s course is a little more complicated than that, though. The sun actually moves across the sky differently depending on where you live and the time of year because of the earth’s eccentric orbit and natural tilt.

We examine the implications of the sun’s shifting position for solar energy generation in this blog post, as well as how to arrange your panels for optimum performance. We’ll also go through the several criteria that determine the ideal solar panel angle. Finally, we consider the actual significance of achieving the ideal angle.

But first, a brief reminder: solar panel tilt is another name for solar panel angle. Both in this text and online, the terms are frequently used interchangeably.

What does “solar panel angle” mean?

Another term for the vertical tilt of your PV system is solar panel angle. A solar system has no tilt when it is parallel to the ground. It is at a 90° angle if it is erect and perpendicular to the ground.

Your solar panel’s angle, which depends on two elements—latitude and season—can alter how much solar electricity you produce.

You may increase the amount of solar electricity generated by optimizing and altering the tilt of your solar panels in accordance with these variables.

What is the best solar panel tilt for your latitude?

The tilt angle grows with latitude; therefore, the farther your home is from the equator, the larger the tilt angle should be.

For instance, the sun rises higher in the sky in states with lower latitudes (such Arizona and Hawaii). For direct sunlight to reach solar PV panels in these states, a low tilt is necessary.

On the other hand, the sun is lower in the sky in higher latitude states like Minnesota and Oregon. In order to receive the most sunlight in those states, solar photovoltaic panels should be positioned at higher tilt angles.

How can you determine the optimum angle for solar panels for your state?

The ideal tilt angle for fixed-mount solar panels can be determined using a straightforward rule of thumb. During the summer, deduct 15 degrees from your location’s latitude, and in the winter, add 15 degrees.

Use the second formula on this page to determine tilt angle for an exact method.

For instance, in the San Francisco Bay Area, a tilt angle of 22 to 23 degrees is ideal for solar panels. The ideal solar panel tilt for Los Angeles is 19 degrees.

If you choose a fixed installation, these angles will provide you with the best total production over the course of the year. Actually, by altering solar panels dependent on the season—which we discuss in the next section—you may enhance energy production even more.

What is the best solar panel tilt for each season?

Along with variations in latitude, the angle of the sun also varies with the seasons. The sun is lower in the winter and higher in the summer, as indicated in the figure below.

This implies that you would need to make adjustments for each season if you wanted to make sure that your solar panels are always positioned for maximum exposure to sunshine.

The ideal solar panel angle for each state in the U.S. during the winter, spring/fall, and summer is shown in the table below.

Optimum solar panel angles for various U.S. cities

A system at 40° latitude enjoys a significant energy boost of 4.1% if adjusted just twice a year.

An additional two adjustments for spring and fall can yield an additional 0.5% output — see below.

How changing the angle affects solar panel output

However, it is not an easy chore to adjust your solar panels four times a year (or even just twice). After all, the majority of solar panels are fixedly angled roof mounts that cannot be moved.

A ground-mount system and the installation of axis-tracking solar panels are the only ways to effortlessly modify solar panels. This strategy does enhance solar production, but there is a significant drawback—it substantially raises your costs. Solar axis trackers are therefore not currently financially viable.

Do you now wonder why, even after accounting for each season, you still only achieve 75.7% of your maximum output? That’s because correcting for solar panel direction during the day is the only way to get the remaining amount.

How does having a shallow vs. steep roof angle affect solar production?

The output of solar panels installed on a shallow (15 degree) roof and a steep (45 degree) roof differs only slightly over the course of a year, according to research.

This is because throughout the course of a season, the various pitches will balance one another. Solar panels on a steep roof will generate more power during the winter, whereas solar panels on a shallow roof would capture more sunlight during the summer.

While solar panel trackers can be used to keep panels at the best angle at all times, in most situations they aren’t worth the price and hassles.

Therefore, regardless of the installation angle, the majority of homeowners in solar-friendly regions like California believe that solar systems are worthwhile investments.

California’s solar statistics, as displayed in the figure below by the Energy Information Administration, serve as proof of this.

Conclusion: Solar panel angle matters, but not that much

The inclination angle of solar panels has an impact on their efficiency. You would have to modify the angle based on latitude and season to get the most power out of a PV system.

Real-world situations frequently involve set roof angles, leaving no room for the solar systems to be tilted or adjusted.

In order to meet the various roof pitches found on residences, solar systems are placed over a range of tilt angles, effectively saving homeowners money.