Solar energy is taking off in the US. In 2019, the solar industry will likely surpass 2 million residential rooftops with solar panels installed nationwide. Some states and cities are further along in the adoption of solar energy than others, while others are new markets poised to become leaders in future years. To breakdown the best cities and states for solar in 2019, we leveraged our own data as well as the recently released Shining Cities 2019 report from Environment America.