The solar streetlights we work with are designed for Michigan winters. The battery bank is built to have 5 days of autonomy, meaning that with a full charge they will function even if they get no sun for 5 days. Michigan gets an average of 4.5 sun hours per day, which dips down to 2.5 in the winter months. However, we still get more sunlight than Germany, which has been leading the world’s solar market for many years.