With the rising cost and dwindling supply of fossil fuels, alternative energy sources like solar and wind power become more popular and, more importantly, more competitive cost- and output-wise. And although it’s not unusual to see solar panels dotting rooftops across the United States, it is unusual for individual consumers to sign the same sort of contract that a business would sign for solar panel use: building owners sign contracts with solar developers for long-term maintenance and the power supply. When Lynn Jurich founded SunRun in 2007, she did exactly that.

Five years later, and, remarkably, SunRun has relatively little competition, is more stable and is seeing more growth than ever before. Shortly after its founding, the San Francisco-based company grew quickly thanks to $12 million in venture capital funding. Thanks to their business model, SunRun lowers the cost hurdle that faces most consumers who want to switch to solar power. Rather than consumers buying the panels outright — which can cost upwards of $30,000 — SunRun owns the panels and maintains them, the consumer pays a fixed rate for a set period of time for the electricity generated. The cost of SunRun’s solar power runs about the same as traditional power, but in some markets the cost is lower; no matter where you are, the environmental benefits are higher than traditional power sources.

Now the nation’s leading residential solar company, SunRun installs more than $1 million in solar equipment every day. Currently, the company services only nine states — Arizona, California, Colorado, Hawaii, Maryland, Massachusetts, New Jersey, Oregon, and Pennsylvania — but with its continued growth, it hopes to add more. With SunRun plans starting with no money down, and a fixed, twenty-year rate immune to the volatile energy market, it’s easy to see why SunRun is number one.