Weather in the Madison area often brings cloudy days, especially during winter and spring. Although cloud cover does reduce sunlight, solar panels are designed to capture available light and convert it into usable energy, even in overcast conditions. Here’s an explanation of how solar works on cloudy days and what output you can expect.
Are Solar Panels Effective on Cloudy Days?
Yes, They Are: Solar panels can generate electricity in low-light conditions, just at a reduced capacity.
Efficiency Rates: On cloudy days, solar panels may operate at 10-25% of their potential output, depending on cloud density and solar panel type.
What Can You Expect from a 400-watt Solar Panel on a Cloudy Day?
Typical Output: A 400W panel might be producing between 50-150 watts on a moderately cloudy day. To put that in perspective, an average refrigerator uses between 300 and 800 watts.
Location & Cloud Density: Results vary depending on cloud thickness, time of day, and location. Madison’s latitude means clouds can reduce efficiency more than in sunnier regions, but solar remains viable year-round.
How Much Energy Will a 10-panel (4 kW DC) Solar System Produce on a Cloudy Day?
Estimated Output: Ten panels will likely produce around 500-1,500 watt hours on a winter day during overcast conditions. That’s more than enough to run an average refrigerator and more on a cloudy day.
Optimizing for Low Light: Using high-efficiency panels and strategic placement can help maximize output, even on cloudier days.
How Does Midwest Solar Account for Cloudy Days?
We incorporate cloudy days and snowy days into all system designs.
We utilize a solar production calculator from the National Renewable Energy Lab that includes several factors like; azimuth, panel tilt, losses from shade, snow, soiling, efficiency loss, maintenance and more, to determine each system's annual solar production.
System Design Matters: We incorporate microinverters, optimizers and string inverters with optimization software to improve performance in less than ideal conditions.
Why Solar is Still Worth It in the Madison Area
Despite reduced output on cloudy days, solar power remains a good investment in and around Madison:
Year-Round Efficiency: We are able to design most home solar systems so that the total annual production of the system is enough to offset your total yearly electrical usage through net metering.
Net Metering: Panels generate more electricity in the peak of the day especially in the summer; this leads to overproduction compared to customer usage during those moments. The extra electricity produced can be banked in the form of credits from your utility to be used at night or cloudy days for example. If you are unsure of your utilities rules on net metering or how excess production is credited, reach out to us and we can help.
Learn More About Net Metering in WI.
Final Thoughts
While cloudy days impact solar output, Madison-area residents can still benefit significantly from solar energy. With advanced panel technology and seasonal net metering, you can enjoy reliable energy and savings year-round. Even with all of the snowy and cloudy days in Wisconsin, most systems we install see their system paid for in 8-12 years through their saved electricity costs.
Comments