Sheepdogs may now be considered an important part of green energy. Solar farms in Europe have begun keeping sheep in the pastures beneath solar array farms. The sheep are a green way to keep the weeds and grasses from blocking the sunlight. A fence around the solar farm keeps the sheep in and the people out. Sheepdogs like Border Collies have hit the spotlight helping to move the sheep around. The sheep cut the grass for free and provide wool.