Can You Put Solar Panels Over Skylights?

Installing solar panels over skylights is a popular idea for homeowners looking to maximize solar energy production while still allowing natural light into their homes. Skylights provide natural lighting and ventilation, reducing the need for artificial lighting during the day. Meanwhile, solar panels convert sunlight into electricity. At first glance, solar panels and skylights seem compatible – after all, they both rely on the sun’s rays. However, there are important considerations when combining these two technologies on the same section of roof.

In this article, we’ll explore the pros and cons of installing solar panels over skylights. We’ll look at skylight options compatible with solar panels, optimal solar panel orientation, alternate installation configurations, aesthetics, costs, safety and more. With careful planning, solar panels and skylights can complement each other, allowing you to reap both energy and natural lighting benefits. However, unique challenges of this type of setup need to be addressed to ensure proper functioning of both systems.

Pros of Solar Panels Over Skylights

Installing solar panels over skylights can be an effective way to generate clean, renewable energy from the sun while still allowing natural light into your home. Some of the benefits of this setup include:

Solar panels convert sunlight into electricity without producing greenhouse gas emissions. Positioning them above skylights enables you to harness the sun’s energy for power generation while letting light filter into the rooms below the panels. This allows you to reduce your home’s carbon footprint and reliance on fossil fuels while maintaining brightness and openness. According to the U.S. Department of Energy, solar energy systems can offset 30-60% of household electrical needs.

With solar panel costs decreasing over time, going solar is becoming more affordable for homeowners. The panels can help lower electric bills over the decades-long life of the system. For many homeowners, the long-term energy savings end up offsetting the upfront installation costs of the solar array. When positioned thoughtfully over skylights, the panels can allow you to harness the power of the sun both as an energy source and a light source.

Cons of Solar Panels Over Skylights

One of the biggest downsides of installing solar panels over skylights is that it can block natural light from entering the home. Skylights are specifically designed to let daylight in, brightening up interior rooms and reducing the need for artificial lighting during the day. Covering skylights with solar panels will diminish this benefit, resulting in darker rooms.

According to a study by the U.S. Department of Energy’s (DOE) National Renewable Energy Laboratory (NREL), proper daylighting design can reduce lighting electricity use by up to 80%.^[1] With solar panels on top of skylights, these potential energy savings would be lost. Homeowners may need to keep lights on more often.

In addition, some research suggests exposure to natural light has mental and physical health benefits. Blocking natural light from skylights could impact mood, sleep, focus and more for occupants.[2] This is an important factor to consider when weighing solar panel placement.

[1] “Solar Panels on Roof Shingles: Pros and Cons”

[2] “Advantages and Disadvantages of Solar Panels On Roof”

Skylight Options

There are a few common types of skylights to consider for your home. The main options are glass, plastic, and tubular skylights.

Glass skylights like fixed or venting allow the most natural light into a space. They are made of tempered glass which is durable and impact resistant. Glass skylights have a classic aesthetic but are generally the most expensive option (https://ranchroofing.com/types-of-skylights/).

Plastic or acrylic skylights are a lighter and more affordable option. They are not as durable as glass but still let in diffused natural light. Plastic skylights may become brittle and yellow over time. They come in both fixed and venting styles (https://vividskylights.com.au/types-of-skylights/).

Tubular skylights, sometimes called sun tunnels, use reflective tubes to bring natural light from the roof into the home’s interior. They do not have as large of an opening as standard skylights but still brighten up a space. Tubular skylights have the benefit of being the most affordable option that is still energy efficient.

Orienting Solar Panels

To maximize solar panel efficiency, it’s important to orient them in the optimal direction and angle. The best direction for solar panels in the northern hemisphere is due south, because this maximizes exposure to direct sunlight throughout the day (Sunrun, 2022). Angling solar panels between 15-40 degrees also boosts efficiency, with steeper angles being better in the winter and shallower angles optimal for summer (EnergySage, 2022).

Specifically, solar panels tilted at latitude plus 15 degrees provides close to optimal annual energy production. So for example, if you live at 35°N latitude, tilting panels at 50° maximizes efficiency. Using online calculators can help determine the specifics based on location.

Alternate Installation Options

There are a few options for installing solar panels near skylights without directly covering them. According to Green Ridge Solar [1], the most common are:

Side by Side: Solar panels can be installed right next to the skylight, leaving a gap between the two. This allows both the skylight and panels to function properly. The gap should be wide enough to allow proper airflow and prevent overheating. Many installers recommend at least 1-2 feet between the skylight and solar panels.

Partial Coverage: The solar array can be designed to only partially cover the skylight. For example, panels can be aligned to leave the northern portion of the skylight uncovered to allow natural light in. The key is ensuring the uncovered portion allows sufficient light for the skylight’s purpose.

Proper planning is important with these alternate installation options to maximize solar production without blocking too much natural light from entering through the skylight.

Aesthetic Considerations

The visual appeal of solar panels is an important factor for many homeowners. Although solar panels serve an important functional purpose, their appearance can impact the curb appeal and aesthetics of a home. According to Solar Panels in Art and Design Merging Aesthetics and Functionality, designing solar panels with aesthetics in mind offers several advantages such as increased adoption and positive public perception.

There are a few ways to make solar panels more visually appealing. Orienting the panels in an organized, uniform pattern can give a clean, modern look according to The Aesthetics of Solar Panel Rows Patterns and Visual Flow. Strategic placement is also important – solar panels over skylights would block natural light. Mounting options like solar shingles or solar skin can seamlessly integrate panels into the architecture per Transforming Urban Landscapes with Solar Skin Technology. With careful planning, solar panels can enhance, rather than detract from, a home’s curb appeal.

Cost Analysis

The cost of installing solar panels varies greatly depending on the size of the system, but on average, solar panels cost around $3 per watt to install according to EnergySage^[1]. For a typical 6kW system for a home, that would be about $18,000 before incentives. Meanwhile, skylights can provide energy savings and reduce electricity bills. According to VELUX Skylights^[2], their skylights provide savings of around $13 per month on electricity bills. So over the lifespan of a skylight, the energy savings can offset much of the upfront installation cost.

When weighing the costs of solar panels versus skylights, it’s important to consider the goals. Solar panels can completely offset electricity usage when sized properly, while skylights reduce bills but don’t eliminate the need for electricity. For many homeowners, installing both options creates synergies – solar panels provide clean energy while skylights reduce the amount of electricity needed in the first place through passive lighting and ventilation.

In terms of return on investment, solar panels may offer a faster payback and higher long-term savings. But for those seeking to reduce energy bills through passive solar, skylights are a smart investment that can pay for themselves over time^[3]. With energy efficient models like those from VELUX, monthly savings from skylights can offset much of the upfront cost over the product lifetime of 20-30 years.

Ultimately, solar panels and skylights work very well together to reduce home energy costs. Solar handles active electrical generation while skylights provide passive energy savings. For many homeowners, installing both systems creates an optimal situation.

^[1] https://www.energysage.com/solar/101/how-much-do-solar-panels-cost-for-your-home/

^[2] https://whyskylights.com/skylight-costs

^[3] https://www.dryhome.com/do-skylights-save-me-money/

Safety Factors

Installing solar panels over skylights does come with some safety considerations. The main risks to consider are fire hazards and issues with wind or extreme weather.

Solar panels can get very hot, especially on sunny days. Placing them directly over a skylight could pose a fire risk, as the heat from the panels radiates downwards into the home. There should be sufficient space between the solar panels and skylight to allow for airflow and prevent overheating [1]. Most experts recommend at least 18 inches between solar panels and skylights.

Solar panels can also catch strong winds like a sail. If they are not properly secured, wind uplift forces could damage the panels or the underlying skylights. It’s important that the solar panel mounting system is engineered to withstand wind speeds for the given area. Skylights should also be impact-resistant models to avoid cracking from hail or debris blown by winds [2].

Overall, with proper spacing and structural reinforcements, solar panels can be safely installed over skylights. However, caution is warranted to mitigate fire and weather risks.

Conclusion

In summary, installing solar panels directly over skylights is generally not recommended. While it may seem like an efficient use of roof space, the cons tend to outweigh the pros in most situations.

The main downsides are reduced light from the skylight, inefficiency of the solar panels due to uneven lighting, and aesthetic considerations. However, with careful planning, there may be some instances where solar over skylights can work, such as smaller panels or tubular skylights.

The best solution is often to orient solar panels in an optimal direction for maximum sunlight exposure. If roof space is limited, consider alternate locations like ground mounts or solar carports. For skylights, use heat-resistant glass and consider larger sizes or more skylights to compensate for shading.

In the end, it comes down to your priorities and a cost-benefit analysis. If natural light is paramount, avoid placing panels over skylights. But if solar power generation is the top concern, an alternate skylight and solar layout can be designed to achieve both objectives.