how wind impacts solar panels

How Wind Affects Solar Panels?

Solar panels are an unavoidable roof addition to install in order to save money on power and help the environment. Panels are now so sophisticated in technology that they may be nearly imperceptible or become a one-of-a-kind addition to your roofing system. Because of all the great experiences, an increasing number of individuals are deciding to install them in their homes.

Several variables influence solar panel efficiency. The most critical aspects in how efficient solar panels are the type of solar cells used and how the panels are built. Aside from the inherent capabilities of the panels, environmental conditions have a role.

Unsurprisingly, sunlight is the second most important environmental efficiency element. Dust, humidity, and wind velocity are next in order. Those in a quandary, on the other hand, are frequently concerned about how effective solar panels will be in their specific environment. Another issue that individuals are concerned about is whether or not severe winds would harm their solar panels.

Wind’s Impact on Solar Panels

Another aspect that may add to damage in a storm is wind. High winds from all directions may wreak havoc on even the best-built houses. Uplift may be an issue since the solar panels are placed slightly above the surface of the roof.

Wind can cause uplift when it makes its way between the roof and the solar panels, causing the panels to rise up or break free. However, with the correct installation of quality solar panels, you won’t have to worry about uplift until in the case of really severe weather.

Solar panels from reputable manufacturers are rigorously tested to ensure they are engineered to withstand uplift. Furthermore, properly installed solar panels, in most cases, account for wind patterns to ensure that your solar panels are securely mounted on your roof and that all wires are carefully stowed.

If you reside in a region prone to severe winds, your solar installer will be able to knowledgeable recommendations based on their experience. And, more than likely, your roof will fail before your panels do.

Solar Panels Can Survive Extreme Wind

The good news is that solar panels are being designed and manufactured using materials that can resist gusts of up to 140 mph, which means they won’t be joining Dorothy in Oz very soon. 76 percent of tornadoes have winds speeds ranging from 40 to 112 mph. Local authorities where hurricanes are common frequently impose a higher rating on panels, sometimes going as high as 185 mph. Solar panel damage is more likely to occur during high winds due to big objects pounding onto it. Even yet, it has proven to be a very rare occurrence—the largest Florida utility claimed that Hurricane Irma only damaged .04 percent of the 1,000,000 panels in the storm’s path in 2017. So, while the industry isn’t prepared for every weather event, we’re working hard to become more robust each year.

Temperature, wind speed, and solar efficiency

While wind does not offer the sun’s light beams any additional vigor when powering panels, the impact of wind is a rise in solar efficiency. Here’s how it works.

The technology behind a solar panel generating power lowers efficiency when it gets too hot. Cooler solar panel temperatures, on the other hand, boost efficiency. In a nutshell, the influence of temperature on solar cell performance is that cooler panels allow more energy to pass through like an electric current than hot panels.

This is where the wind comes in. The wind cools the solar panels. Though it won’t make or break your entire solar panel production, it does make a difference. Solar panels that are cooled by 1 degree Celsius are 0.05 percent more efficient. This proportion builds up over time.

Humidity and the Efficiency of Solar Panels

Humidity may stifle productivity in two ways.

  1. Tiny water droplets or water vapor can congregate on solar panels (much like sweat beads) and reflect or refract sunlight away from solar cells. This limits the quantity of sunlight that strikes them and generates power.
  2. Consistently hot and humid temperatures can deteriorate the solar panels themselves over time. This is true for both crystalline silicon cells and thin-film modules, however in tropical climes, cadmium telluride (thin film) solar cells perform around 5% better.

This is particularly true in locations that are continually humid. Tropical regions, such as Florida, are an excellent illustration. This is probably not a surprise if you live in Florida. You’ve seen automobiles corrode faster than most people in dry areas believe.

The effects of humidity on solar panels in humid environments are well known to solar panel manufacturers. There are safeguards that may be taken to prevent humidity from damaging solar panels more quickly, such as employing edge sealants and low ionic conductive materials.

Why should you take wind load into account when installing a solar panel system?

Let’s take a closer look at what wind load is. The wind load is defined as the force exerted on the building (or even the solar PV modules).

This effect is split into two parts: wind pressure loading and wind suction loading. The first affects the building’s windward side, whereas the second affects the building’s windward side.

The wind load is another aspect that must be considered while installing solar PV panels.

This is important for two reasons: wind causes an excessive force on the solar PV modules and the PV mounting system, and wind load impacts how near the solar PV panels must be placed to the roof’s edges. The greater the wind load, the greater the distance to the roof edge should be chosen.

Wind load zones are depicted on the wind load map.

wind zones
Source: Federal Emergency Management Agency

The wind load map of the United States is split into four wind load zones. Each wind load zone is given an average wind speed.

Zone 4 has the greatest average wind speed of 250 miles per hour (111.76 meters per second), while zone 1 has the lowest average wind speed of 130 miles per hour (58.1 meters per second).

The following graph depicts the wind speeds and pressure loads in the four wind load zones:

Wind load zonesWind speedsPressure load
I130 Miles per hour7.80 kN/m2
II160 Miles per hour5 kN/m2
III200 Miles per hour3.19 kN/m2
IV250 Miles per hour2.10 kN/m2

Notice:

One kilo Newton per square meter equates to loading of 100 kg per square meter.

Wind speed (at a height of 10 meters) / 1600 = pressure load

Wind load on solar PV panels

Wind load can be dangerous to solar PV modules. Severe damage might occur if the solar PV panels are ripped from their mooring.

This applies not just to solar PV modules erected on flat roofs or ground-mounted systems, but also to solar PV panels on sloped roofs. Wind load can have a significant impact on them. Wind suction acts as an extra loading in this case.

In the case of the wind suction effect, the distances between the solar PV modules and the roof surface, as well as how near the solar modules are installed on the roof’s edges, are critical.

Wind pressures can be significant, particularly in the gables and at the roof ridge.

Tip: When determining the proper distances between solar PV panels, a balance must be struck between the greatest possible back ventilation and the lowest possible loading due to the wind suction effect.

The manufacturer’s installation requirements must always be followed.

Solar Panel Design for Mother Nature

So, if you’re dealing with humid summer days, keep in mind that your solar panels are feeling the same way. But, just as we humans love a gentle wind to keep us cool, solar panels do as well. Wind aids in the drying of water vapor and cooling of the panels in the same way as a breeze aids in the drying and cooling of human perspiration.

Again, because the wind has the opposite impact on solar efficiency, it frequently helps to balance out the humidity component. It’s another example of mother nature and a little engineering foresight coming through for a clean energy win.