Built for a life outdoors, solar panels can handle all types of weather conditions - from rain and snow to heavy winds and an extremely wide temperature range.
If you are considering solar and worried your local temperatures could pose a potential safety risk, you may find it comforting to know that modern solar panels are incredibly resilient and fit to operate year-round in nearly every climate.
So unless you live in the Arctic Circle or on the sun's surface, solar panels can produce electricity in some capacity on nearly every clear day in the United States. (This is why they don’t make “high-temperature solar panels” or “solar panels for cold weather climates”.) With that said, the amount of solar power you can create will be directly affected by ambient outdoor air temperatures and the solar panels' temperature.
In this quick guide, we will look at how temperature affects solar panels before detailing the best (and worst) temperatures for solar energy production.
The Effect of Temperature on Solar Panel Efficiency
Have you ever felt a little sluggish on a hot summer day? Well, solar panels can feel that way too, sometimes.
Although you might think that your solar power potential will only increase with every degree that temperatures rise because more sun equals more power, heat is not necessarily a solar panel’s best friend. Like many electronics (computers, phones, etc.), high temperatures can cause solar panel efficiency to drop.
When exposed to too high of temperatures, the flow of electricity-generating particles within each solar cell is slowed, reducing the speed at which new solar power can be produced. On the other side of the thermometer, temperatures below a solar panel’s peak operating efficiency rating can also reduce your potential electricity production.
Knowing this, if given a choice between hot summer heat or chilly winter conditions, assuming the same amount of sunlight, most solar panels prefer colder climates, producing more electricity per hour in cool weather (we will dive deeper into this later).
The Best Temperature for Solar Panels
In the wide world of photovoltaic (PV) solar panels, there are many different global products, all with unique technologies, capabilities, and specificities. To put a single number on it, however, it is generally believed that the ideal operating temperature for an average solar panel is around 77 degrees Fahrenheit or 25 degrees Celsius. As such, the manufacturer’s performance ratings of solar panels are usually tested at 77°F (25°C) or what’s called “standard test conditions.”
To get a bit technical, solar panels are rated with specific high and low “temperature coefficients” that represent efficiency losses related to temperature changes above or below 77°F.
For example, let’s say your solar panel has a temperature coefficient of -0.35%. This means that for every degree above 77°F that temperatures increase, your solar panels will lose approximately 0.35% in power production efficiency. Therefore, on an 80-degree day (3 degrees above ideal temperatures) this would lead to an approximate efficiency loss of 1.05% (.35 x 3 degrees).
In this example, with a marginal efficiency loss of 1.05%, your solar panel would work at a power production efficiency of 98.95%. However, this example needs to consider that solar panels usually become much warmer than ambient temperatures while harnessing sunlight throughout the day.
So, although a solar panel may be rated for optimal performance at 77°F, this does not necessarily mean that it will work most efficiently on a 77-degree day.
Operating Temperature Range of Solar Panels
Although extreme conditions will affect solar panel performance efficiency, solar panels are rated to operate in a very wide temperature range. Designed to reflect real-world conditions, most solar panels have an operating temperature range wide enough to cover every single day of your system’s multi-decade lifetime.
For instance, solar panels sold by Mission Solar, Jinko Solar, and Tesla Solar are all rated with an operating range of -40°F to +185°F. When was the last time you experienced a day outside of this temperature range? We are guessing almost never.
In the event of a deep freeze in your area (less than -40°F), your solar panels may be too cold to produce new electricity. While this should only be a temporary issue, monitoring your panels’ performance after the extreme temperatures have passed is a good idea to determine whether or not any permanent damage may have occurred.
Solar Panel Temperature and Seasonality
Generating electricity in various capacities throughout the year, the seasonality of solar panels results from both operating temperatures and the number of daylight hours per day.
In the summer, there are more hours of direct sun per day to produce solar electricity. Therefore, even if your panels worked at reduced efficiency due to the heat, the extended daylight time still allows plenty of solar power potential.
A few months later, cooler outside temperatures could have your solar system working at peak efficiency, albeit with fewer total sunlight hours to produce new power. On cold sunny days, solar panels can even thrive in winter weather, so long as direct sunlight access is not buried beneath a layer of accumulated snow.
Key Insights and Where To Learn More
To recap, outside temperatures may affect your solar panels’ efficiency, but this is nothing to worry about in terms of the long-term performance of your renewable energy system.
Today’s solar panels are built to handle each end of the temperature spectrum, with an operating range that reflects real-world conditions. Although the power output you can produce will depend on the day and season, you can always count on your panels to generate emission-free electricity every month of the year.
If you would like a few key stats to take home, here is a quick look at solar panel temperature range by the numbers…
- Ideal temperature for solar panel efficiency: ~77°F
- Minimum temperature for solar panels: -40°F
- Maximum temperature for solar panels: +185°F
On a solar deep-dive or looking to get solar panels installed?