Actually, as long as there is light, a solar panel will keep on producing energy. Germany, one of the world leaders in solar energy, ranks very low in irradiation intensity of sunshine, but still produces large amount of solar energy. Solar panels are also more efficient in cooler weather than in high temperatures and a professional system and electronic design could help to harvest more energy from the sunshine.
Looking at the science behind the facts, crystalline silicone is sensitive within the spectrum of 350nm and 1150nm. This means that the visible light (spectrum from 380nm to 780nm) and some of infra-red light will generate electricity through photovoltaic panels. Normally. As long as there is a light, solar panel will not stop producing energy.
2. Solar panels are high maintenance