In a future society with limited access to fossil fuels, the availability of technologies for efficient and on demand delivery of renewable energy will be highly desirable. In this regard, methods that allow for solar energy storage and on demand solar driven power generation are particularly relevant, since the sun is the most abundant energy source available. Small solar energy systems can provide electricity for homes, businesses and remote power needs. Additionally, larger solar energy systems provide more electricity for contribution to the national electric power system. Solar energy systems can be divided into two major categories: photovoltaic and thermal. Photovoltaic cells produce electricity directly, while solar thermal systems produce heat for buildings, industrial processes or domestic hot water. Thermal systems can also generate electricity by operating heat engines or by producing steam to spin electric turbines. Solar energy systems have no fuel costs, so most of their cost comes from the original investment in the equipment.