More solar farm operators are realizing, as their plants enter the second and third years of their lifespan, that dust has had a big impact. One operator says cleaning and vegetation management are the two most costly variables in plant O&M — even more expensive than equipment maintenance.

“A few plants did cleaning at the commissioning,” says Grossman, often because it’s in an EPCs contract to do so. “Then they ran the numbers and said, ‘It doesn’t make sense to clean again.’ Since we’ve been able to lower the price, now they’re interested.”