Solar panels are built tough and are certified as such before they ever leave the factory. Whether it's the broiling heat of the American Southwest or the chilly winters in Alaska, solar panels are designed to withstand weather at both extremes.

With winter around the corner, should owners of home solar energy systems take any steps to prepare their system for the season? We have gathered some expert advice for you.

Solar Panels Are Built to Stand Up to Winter

First, it is reassuring to know that solar panels are not designed and manufactured with only year-round sunshine in mind. Although solar panels are more prevalent in states like Arizona, California, and Florida, they are built to withstand a wide variety of climates. As such, solar panels are winter-ready out of the box. Other than clearing them after heavy snowfall, you don't need to do anything extra to your solar panels in winter.

During manufacture, panels are subjected to various stress tests in order to receive the Underwriter's Laboratories (UL) certification. Solar panels stand up to bad weather extremely well. The Energy Department's National Renewable Energy Laboratory analyzed 50,000 solar panel systems over six years and found that only 0.1% reported trouble from damaged or underperforming modules. This speaks to the high quality of solar panels.

The laboratory wrote: "Despite hurricanes, hail, shading, vandalism, and hook-up delays, approximately 85% of all systems each year produced 90% or more of the electricity predicted, and the typical system produces more electricity than predicted. Year to year comparisons suggest that the degradation rate—the gradual loss of energy production—is in the historical range of 0.5%-1% per year."

“Research has shown that solar can still successfully generate electricity in snowy areas and other harsh environments. Light snow has little impact on solar panels because it easily slides off. Heavy snow can limit the amount of energy produced by solar panels, but light is still able to move through the snow and forward scattering brings more light to the solar cells than one might expect.”

Charlie Gay, "Let It Snow: How Solar Panels Can Thrive in Winter Weather," Energy.gov

How to Prepare a Battery System for Winter

Thoughtful winter battery care will ensure that the battery lasts the longest and stays efficient. Here is a checklist to help you prepare your solar battery bank for the season.

Battery storage
Store your battery properly. Batteries need to be protected from freezing and the elements yet not kept in living spaces if they are the common flooded type of battery, which emit hydrogen gas. That's why the garage is an ideal place to install a battery bank. An outbuilding can work so long as it is well insulated and has enough airflow to keep temperatures constant.

Battery performance is affected by both extreme cold and extreme heat. The blog Greener Ideal offers this advice regarding battery discharge and storage.

  • Lead-acid batteries should be disconnected at 100% capacity before long-term storage.
  • Lithium-ion batteries should be discharged to 40% and stored in a cool, well-insulated place.

Perform regular battery maintenance
When you are in the winter-prep mindset, it's a good time to perform the regular maintenance that most batteries need for longevity. Your battery's manufacturer could have specific advice, so look for that, but in general most batteries should get their terminals cleaned, and you should ensure that all connections are secure.

If you spot corrosion on lead-acid battery terminals, don a pair of gloves and clean the terminals with a mixture of baking soda and water. Once they are clean and dry, coat the terminals with high-temperature grease.

If your home has flooded batteries, check the water level before winter. Actually, you should check the level every two months. If the water is low, add distilled water to top it off. Only used distilled water.

Tips for Heating Your Home Efficiently in Winter

Did you know 41% of your energy usages goes to heating your home? That is based on average numbers from typical households. Winter, of course, is when heat consumption is highest.

Here are three tips for keeping your home warm and comfortable in winter. First, lower your thermostat. Lowering the thermostat by just 1 degree saves between $44 and $73 a year on your power bill¹. Second, homeowners typically save $200 a year in heating and cooling costs by air-sealing and insulating their home, according to Energy Star. The EPA recommends sealing air leaks with caulk, weather stripping, and spray foam before insulating. Finally, use the power of the sun to heat rooms whenever possible. Draw open the curtains in the morning in east-facing rooms to capture the day's early warmth. Let sunshine flood south-facing rooms all day long.

What About the Solar Energy System on My RV?

Winterizing your RV solar panels is quite easy, say the experts at Camp Generator. "If you don’t plan on using your RV for the winter months and you want to protect your RV solar panels and the system as a whole, purchase waterproof, lightproof covers for the panels and remove the battery, storing it in a dry, dark place."

Conclusion

Winter prep is easy for a home solar energy system, right? Now you have more time to enjoy the uniquely winter ritual of soaking in a hot tub on a chilly winter's evening, perhaps a hot tub that stayed warm and comforting under a solar blanket! Solar is rewarding and customizable. Connect with a local installer to explore your options today!