Removing snow from solar panels has been a regular debate for the last decade. Various studies claim only a small percentage of production is lost from snowfall. Is it really worth tacking on snow removal O&M costs?
Janitorial solar O&M companies, like Solar Maid, say yes, but not for production claims. Safety concerns are becoming louder in the solar industry. While experts (and Solar Maid) suggest giving Mother Nature time to melt snow off tilted panels, that falling snow can be problematic, especially on public solar arrays like carports.
“It’s becoming a pretty big issue now,” said Jay Welsh, general manager of Solar Maid. “We’ve really seen a spike this year in business.”
Founded in 2003, Solar Maid specializes in janitorial solar O&M—panel cleaning, landscaping, pest abatement—and is headquartered in Pittsburgh but has affiliates in nearly every major market in North America. Snow removal from a safety standpoint is more prevalent on residential and commercial projects. Utility-scale solar arrays turn to Solar Maid in the winter specifically because of production losses.
“Some of those bigger sites lose $80,000 a day when those things aren’t producing,” he said. “They’ll pay us $5,000 or $10,000—it’s certainly a cost benefit.”
Solar Maid uses its own snow rakes to push and pull snow off arrays. Pricing is based on type of snow—wet, heavy snow is more expensive than light, powdery snow just because of time involved to remove it.
“Carports are easier. You just pull the snow off, then we use a plow and push it out of the way of the parking lot,” Welsh said. “Our rooftop commercial jobs are a bit of a challenge because you have a lot of wires and cabling between the panels, so there’s really no place to put the snow. We’ll set up tarps, push snow on the tarps and then drag the tarps to the edge of the roof and then dump them. Every site is going to present some challenges.”
Solar Maid has been installing more snow guards on its residential arrays to prevent snow and ice from falling off the roof.
“Typically, snow falls and then the sun comes out and warms up and that bottom layer of snow starts to melt,” Welsh said. “It may not melt enough to push the snow off, but then it freezes again. Then you have a sheet of ice, and it snows on top of it. It’s likely not going to stay in one place. If the panels happen to be on the front of your house, if you slam your front door shut, the snow avalanches.”
“Block guards” are randomly placed and clamped to the edge of panels to stop ice sheets, while the typical “snow guard” acts as a lip, attaching to the end of panels to hold back snow.
Solar mounting manufacturer EcoFasten Solar and its sister company Alpine SnowGuards offer a snow management system for solar panels—Solar SnowMax. Made of aircraft-grade aluminum fabrication, it’s strong and rugged and clamps directly to the solar panel frame.
“This snow management system was designed to impede a sudden avalanche of snow,” said Brian Stearns, president and founder of EcoFasten Solar and Alpine SnowGuards. “Snow will still crest, rise up and over the top of the snow management system and fall to the ground in a controlled manner. Solar SnowMax allows smaller, managed amounts of snow to drop to the ground slowly, without that massive rush of snow shooting off the roof that you sometimes see in the phenomena of a roof avalanche, especially on frictionless surfaces, such as solar panels or metal roofs.”
So while production losses on small residential and mid-size commercial projects aren’t worrisome when snow falls, it’s wise to keep in mind all safety concerns. Find a snow-specific O&M company in your area, buy your own snow removal gear or install snow guards to gain some peace of mind. SPW