Solar power is an eco-friendly and cost-efficient way to power your home, RV, van, or boat. But if you want to maximize your output and savings from solar power, your solar panel installation must be operating efficiently.
Many factors impact the efficiency of your solar panels, including how much shade you have over your property and the seasonal weather in your location. Many of these factors are out of your control, but there is one easy factor you can control - the tilt of your solar panels.
When switching to solar power, make sure you don't underestimate the importance of the orientation and inclination of your solar panels! Whether you're installing solar panels on a roof, on the ground, or your van, RV, or vehicle, the tilt of your solar panels always matters. The wrong angle can have a significant impact on your panel's solar energy output, making your system inefficient and more expensive in the long run.
You don't necessarily need to have a south-facing rooftop or live in the sunniest state to see the financial benefits of solar power. But these factors can certainly impact the solar ROI you will get from your solar panel investment.
So when it comes to your solar panel's performance, how much do orientation and the tilt angle really matter? Read on to learn more.
Why is the tilt of solar panels so important?
The power of a solar panel relies fundamentally on clear, unobstructed exposure to sunlight. The sun's path changes as it travels across the sky every day, impacting your solar panel output.
Do solar panels need to be angled?
Your solar panels' tilt, or angle, is crucial because solar panels produce their maximum energy when the sun is directly perpendicular above them.
The tilt or angle of a solar panel refers to the way it is installed. If a solar panel system were level with the ground, then it would be at a 0° angle or tilt. But if it were standing upright and perpendicular to the ground, it would be at a 90° angle or tilt.
An angle is recommended because a tilted solar panel will be closer to the sun and be able to collect energy more efficiently. The photovoltaic cells (PV) in solar panels produce more power when the angle at which sunlight hits the panel surface (also known as the "angle of incidence") is smaller.
What is the optimal angle to tilt your solar panels?
Everyone wants to see the best return on investment from their solar panels. The proper installation can produce more energy that can power your home, charge solar batteries, or be sold back to your utility provider.
So what's the optimal angle to tilt your solar panels for maximum returns?
In the United States, solar panels are at their most effective if installed on South-facing roofs. It's commonly agreed that optimal solar energy production will occur when your solar panels face south at a tilt equal to 30°.
But don't jump to rule out solar panels just because your roof doesn't face directly south! In many situations, you buy the house first before considering adding solar panels. So you'll often just have to deal with the latitude and angles of the roof you have when adding solar panels for your home.
Solar panels can still produce plenty of solar electricity even if they are installed on east or west-facing roofs. East-facing panels can produce more energy in the morning, while west-facing panels will produce more energy late afternoon.
Depending on your lifestyle, this schedule may suit your energy usage needs ideally. A solar panel installation with an east/west orientation can produce more solar energy in the morning and the evenings, but less during the day. This may be fine if you're away from your home and don't use much energy during the middle of the day.
However, solar panels installed facing directly west or directly east will produce around 20 percent less electricity overall than they would if installed facing south. Twenty percent less energy production is often not a big issue if you live in a state with plenty of sunlight hours. However, if other factors are also impacting your solar efficiency, it may be more of a concern.
Installing solar panels on east or west-facing roofs won't prevent you from saving money with solar power. However, if you want to go off-grid or meet your electricity needs with solar power, you will want the ideal installation. You may require a few more solar panels to make up for the loss of energy you could otherwise have produced with a southern-facing system.
We've covered south, east, and west-facing roofs, but what about northern-facing roofs? It is certainly not impossible to install solar panels on the north side of your roof. However, a north-facing panel is the worst possible location for solar production.
If a north-facing installation is your only option, you'll likely need to purchase additional special mounting to generate electricity. Special mounting can be used to allow the panels to oppose your roof's natural slant.
How can you determine the optimum angle for solar panels for your state?
America is a big country where some areas have lower or higher latitudes than others. Because some states are closer to the equator, it's natural that the ideal angle for solar panels can differ from state to state.
Solar panel efficiency from one state to another can be affected by two main factors: latitude and the season. Understanding how seasons and latitude affect your energy output in different states will allow you to optimize and adjust your solar panel tilt accordingly.
What is the best solar panel tilt for my latitude?
Latitude refers to the distance you are from the equator. If you live somewhere further from the equator, then your tilt angle should be higher.
States like Minnesota and Oregon have higher latitudes, meaning the sun is lower in the sky. In states like these with higher latitudes, your solar panels need to be installed at higher tilt angles so they can receive the maximum amount of sunlight.
On the flip side, states like Arizona and Hawaii have lower latitudes, and the sun is higher in the sky. In low-latitude states, your solar panels work best with a low tilt so they can more easily capture direct sunlight.
So, how can you determine what the optimum angle is for solar panels in your own state?
Just follow this simple calculation!
To calculate the best tilt angle for roof-mounted solar panels, you should add 15 degrees to your location's latitude during winter and subtract 15 degrees from the latitude during summer.
The optimal tilt can also significantly impact your wallet if you live in a state with high energy costs. A 20% loss in efficiency from east or west-facing roofs will have a bigger impact financially if you live in a state or city like New York, where electricity is very expensive.
What is the best solar panel tilt for each season?
Latitude is essential in determining the best tilt for your panels, but seasonality is also significant. The ideal position can change throughout the year as the earth moves and the sun's angle to your home changes.
Homeowners can increase their solar energy production throughout the year by adjusting their solar panels.
Here is the ideal panel tilt based on the season:
- Spring: During the spring months, the best angle for your solar panels is a 45° tilt.
- Summer: In the summer, the sun will be higher in the sky, so it's ideal for panels to have a low angle at 20°.
- Winter: During the winter months in the northern hemisphere, the sun is lower in relation to the horizon. So in the winter, solar panels get their best performance at a steeper angle of 60°.
When should I adjust my solar panel tilt?
If you really want to maximize your solar energy production, you will want to ensure your solar panels are positioned for maximum sunlight exposure throughout the year. To do this, you can adjust them for each season.
Adjusting your solar panels every season is easier said than done. To optimize your panel's tilt year-round, you would need to adjust them four times a year. Doing this, or even changing only twice a year, is not always possible or straightforward.
Most solar panel installations will have the panels mounted to the fixed angle of the roof, and they can't be adjusted. There is often no real option to adjust or tilt your solar systems.
It's worth running the numbers to calculate if seasonal adjustments will have a significant impact on your energy costs. If they do, it may be worth utilizing a ground-mount system and installing axis-tracking solar panels.
Axis-tracking solar panels require a more significant investment than regular solar panels, and while they can increase solar output, they will also make your installation more expensive upfront. In many cases, installing solar axis trackers just isn't worth the initial investment.
Is your roof suitable for solar panels?
You might be surprised to learn that the angle of your actual roof has less impact on your solar panel's performance than the direction it faces.
Many people mistakenly believe that they can't switch to solar power because of the angle or material of their roof. This is a common misconception, and most people can successfully install solar panels regardless of their roof's material, location, or dimensions.
There is relatively little difference in energy output between solar panels installed on a steep (45 degree) roof compared to a shallow (15 degrees) roof. Over the course of a year, the different pitches of roofs will usually balance out as they produce more or less energy across seasons. In the summer season, solar panels installed on a shallow roof will capture more sunlight. But in the winter, a steep roof will see more energy production from its solar panels.
Of course, there are some factors that make one roof more or less suitable than another, but you can work with most of them. For example, if you have a lot of shade caused by trees, you may be able to trim or move the tree - or the solar panel. There are very few roof qualities that ultimately prevent solar panel installations; most other factors will have only a minimal impact on the performance of your solar panel system.
Don't forget that roof-mounted solar panels aren't your only option. Even if you rule out a roof installation, ground-mounted solar panels can still be very efficient.
Make the switch
Switching to solar power comes with a vast range of benefits to both your annual bills and the environment. Understanding the importance of a panel's tilt can help you get the best possible return on your installation investment. But even those with a less than ideal tilt shouldn't be deterred from switching to solar power.
Even if your home's solar panels don't sit at the perfect south-facing angle, they will still deliver you significant financial returns.
Most American homeowners will find solar power systems to be well worth the investment, regardless of the angle they are installed at.