Quick answer
Solar panels work in Illinois winters, though short days mean December and January produce far less than June. Snow usually slides off tilted panels within a day or two of sun, so you don't need to clear it. Panels are tested to survive hail, and cold actually improves their efficiency. Net metering credits from sunny months help cover the winter dip.
How much do solar panels produce in an Illinois winter?
Less than in summer. Short days, low sun and the occasional snow cover mean a December or January month often produces only a third or so of what a June month does. Over a full year, Illinois panels still produce about 1,200 to 1,330 kWh per kW, depending on how far south you are.
Because credits for exported power carry forward on your bill, a strong spring and summer helps cover winter. That's why systems are sized on annual use, not a single month. See how net metering works in Illinois.
Should I clear snow off my solar panels?
Usually no. Panels are dark, smooth and tilted, so snow tends to slide off once the sun comes out, often within a day or two. The output you lose in that time is small.
- Don't climb on the roof or use a shovel, scraper or hot water, which can scratch the glass, crack panels or void warranties.
- A soft foam roof rake used from the ground is fine for low panels, if you can reach without pulling on the panels or wiring.
- Watch for ice dams along the roof edge, which are a roofing issue rather than a solar one.
Can hail damage solar panels in Illinois?
Panels are built for it, though no roof material is hail-proof. To earn standard IEC 61215 certification, panels must survive 25 mm (1-inch) ice balls fired at about 23 meters per second (roughly 51 mph) at multiple points on the panel. Many manufacturers test to larger hail, and independent labs such as PVEL run tougher hail sequences because the baseline test is modest for hail-prone areas.
- 1
Check your homeowners policy
Make sure rooftop solar is covered, and tell your insurer once it's installed.
- 2
Ask about hail ratings
Compare panels' tested hail size and glass thickness in your quotes.
- 3
After a big storm
Check your monitoring app for a drop in output and look at the panels from the ground; call your installer before anyone goes on the roof.
How much maintenance do solar panels need?
Very little. Illinois rain and snowmelt keep most panels clean enough, and there are no moving parts. The main tasks are watching the monitoring app for unexpected drops, keeping trees trimmed so new shade doesn't creep in, and having the installer check wiring and mounts if output falls. Inverters typically need replacing once during a panel's 25-plus-year life unless you have a long inverter warranty.
Cold doesn't hurt panels; they're slightly more efficient when cold. Bitter-cold, clear days after a snowfall can be some of the best production days of winter once the panels clear.
Sources
This guide is general information, not tax, legal or financial advice. Incentive programs change, so confirm current terms with your installer, your utility and a tax professional.