The sun behaves differently in the four seasons. And this will affect the performance of the product since the solar brick light uses the sun as an energy source. During the summer solar products generally work very well, and during the winter the performance decreases. The same is true with the Solar Brick Lights. For a better understanding, take a look at the tables below and find out how solar radiation behaves during the different months of the year. References: National Renewable Energy Laboratory Resource Assessment Program.