The solar as a service (SOaaS) segment is experiencing a transformation as the global solar market continues to evolve. SOaaS is a recent phenomenon that has emerged within the distributed solar PV market space. Companies like Vivint, Sunrun, and SolarCity provide SOaaS offerings to enable customers to either finance the cost of the system or just buy the electricity. These offerings range from utilities? green or solar tariffs to solar service agreements in which the service provider only offers operations and maintenance services to a solar owner. SOaaS offerings were launched primarily by Sunrun and SolarCity in the late 2000s and were popularized between 2010 and 2015. Until 2014, it seemed that solar leases and power purchase agreements (PPAs) were going to be the winning business model in the SOaaS industry. But in 2015, the market share of solar leases and PPAs in California, which itself represents around 60% of the US market, plunged to under 50%. This decline forced traditional SOaaS players like SolarCity, Sunrun, Vivint, and SunPower to consider joining financial players and offer loans instead of leases or face losing market share in the United States. SOaaS providers should focus on unlocking value otherwise unavailable to customers, as this creates a win-win situation for solar service players. To survive, solar leasing and PPA providers could transform into virtual power plant (VPP) providers and benefit from the new revenue streams. This Navigant Research report analyzes the different business models for SOaaS providers. The study examines the weaknesses of the various current business models and suggests a more sustainable model that the industry could adopt worldwide. SOaaS contract options are discussed, with a focus on models that will enable SOaaS providers to remain competitive in a changing solar energy environment.