Conventional hydroelectricity works very well in conjunction with solar power, water can be held back or released from a reservoir behind a dam as required. Where a suitable river is not available, pumped-storage hydroelectricity uses solar power to pump water to a high reservoir on sunny days then the energy is recovered at night and in bad weather by releasing water via a hydroelectric plant to a low reservoir where the cycle can begin again. However, this cycle can lose 20% of the energy to round trip inefficiencies, this plus the construction costs add to the expense of implementing high levels of solar power.
Most current solar power plants are made from an array of similar units where each unit is continuously adjusted, e.g., with some step motors, so that the light converter stays in focus of the sun light. The cost of focusing light on converters such as high-power solar panels, Stirling engine, etc. can be dramatically decreased with a simple and efficient rope mechanics. In this technique many units are connected with a network of ropes so that pulling two or three ropes is sufficient to keep all light converters simultaneously in focus as the direction of the sun changes.
The generator, which is approximately 34% of the wind turbine cost, includes the electrical generator, the control electronics, and most likely a gear box (e.g. planetary gear box), adjustable-speed drive or continuously variable transmission component for converting the low-speed incoming rotation to high-speed rotation suitable for generating electricity.
Innovative programs around the country now make it possible for all environmentally conscious energy consumers to support renewable energy directly by participating in the "green" power market. The willingness to pay for the benefits of increasing our renewable energy supplies can be tapped within any market structure and by any size or type of energy consumer.
Photovoltaics were initially solely used as a source of electricity for small and medium-sized applications, from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system. Commercial concentrated solar power plants were first developed in the 1980s. The 392 MW Ivanpah installation is the largest concentrating solar power plant in the world, located in the Mojave Desert of California.