Wind-turbines can be installed on top of a roof of a building. These rooftop wind turbines constitute one percent of the renewable energy market, and have a huge potential in urban and suburban areas. There is not a large market for them yet, but the benefits of these wind systems can include independence from the grid, and payback periods as little as five years. They demonstrate that it is possible for an individual residence to acheive 20 percent wind power in less than a year.