Assuming that birds care about the environment a little more than humans, supplying their homes with solar energy makes perfect sense. OOOMS DutchDesign must think that eco-friendly is for the birds, because they designed this birdhouse with a solar panel on its roof. During the day sunlight feeds the solar panel, charging a small battery inside. At twilight the transparent stick will light up and cast a tiny light on your garden and welcome the birds home.