How Does Winter Impact Solar Energy Production?
A persistent misconception we often encounter in promoting the benefits of solar energy is the belief that solar panels only produce reliable energy in dry, southern climates where the sun shines almost every day, all year long. But, believe it or not, solar energy production works well even in the northern parts of the country where winter brings freezing cold, short days, and long nights. In this blog post, we explain why.
When Air Temps Go Down, Solar Efficiency Goes Up.
Many people are surprised to learn that cold climates make for ideal operating conditions for solar panels. The photovoltaic cells inside a solar panel produce an electrical current when they absorb sunlight, but as they do so, they also get hot. That rising heat inhibits the cells' ability to conduct electricity, making them increasingly less efficient. Solar engineers often build cooling systems into solar panels installed in warm climates to keep them running at near-peak efficiency, but those systems represent a trade-off because they require some amount of energy to run. The ideal operating climate for a solar panel is one where the outside air temperature will cool the panels passively and cost-free – such as a sunny, cold day in the middle of winter!
Shorter Days, But High Energy Prices
You may think that because days are short in the winter, solar panels won't produce enough energy to make them worthwhile. Think again. Energy prices tend to rise in the winter in regions of the country where temperatures fall to near or below freezing, due in large part to homes and businesses consuming more energy for heat. So, even though a rooftop solar installation may have fewer hours in the day during which it can produce energy, the cost savings of that energy is also higher than in other seasons, particularly when it is being produced during hours of peak or near-peak energy use.
Power Production Even When the Sun Doesn't Shine
Did you know solar panels produce energy even on cloudy days? It's true! They don't produce as much energy on cloudy and rainy days than they do when the sun shines, but they also don't go dormant altogether either. On a cloudy winter day, solar panels may produce up to 25 percent of their optimal energy output. Even at those levels, the cost savings can still work to the owner's advantage, because of the higher energy prices noted above.
Net Metering Smooths Out Seasonal Variation
In many parts of the country, owners of rooftop solar installations can sell the excess energy they produce back into the power grid for a credit against current or future energy bills. Over the course of a year, this "net metering" allows rooftop solar producers to "smooth" their energy costs to a relatively consistent and predictable level. In the summertime, the long, sunny days enable owners to produce significant amounts of excess power that builds up credit for them to use during the, short, cloudier winter days when their panels produce less.
Learn About Solar Efficiency Where You Live
So, long story short: solar panels can produce energy during the winter, even in cold, cloudy climates. They make good sense as investments in many of those places because of the higher cost of energy during the winter months, and the long days of producing (and banking credit for) energy in the summer. Have questions about how efficient and cost-effective a solar installation may be in your neck of the woods? Contact Ask Solar today by filling out our online form and letting us help you calculate your potential energy cost savings from installing a solar array on your home.