Solar energy – the most abundant source of energy on earth – is soaring in popularity among homeowners and businesses alike. According to the U.S. Department of Energy, the demand for solar in the U.S. is at an all-time high, with installations increased more than 23 times from 2008 to 2015. UW–Madison researchers are focusing on further reducing the cost of solar energy by improving existing solar technologies, developing new technical and material innovations, and finding ways to decrease installation costs.