Solar Photovoltaics

Cost Effective Power From the Sun

Solar cells, also called photovoltaic cells by scientists, convert sunlight directly into electricity. This electricity is direct current in nature and must be converted to alternating current to be used for grid-connected power generation.

Over the last two decades, solar panel efficiencies have increased dramatically, with today’s typical panel efficiency ranging from 12-18%, although efficiencies of more than 40% have been achieved (NREL).

It is becoming widely recognized that the cost of electrical power from solar generation is already below that of conventional centralized thermal electricity generation in many parts of the world. In most of the United States, solar power generation has not reached grid parity, however, government and other subsidies have made solar financially practical. Grid parity occurs when solar generation is equal to or lower than the cost of power from the grid.

Intermittency coupled with the lack of robust transmission and distribution systems nationwide, is the main reason solar power generation has not been adopted as the world’s primary energy source. Since solar energy is produced when the sun is shining and drops to negligible amounts when there is cloud coverage and during the night, traditional thermal power generation that includes coal, nuclear, natural gas, geothermal, hydroelectric or other power generation must be maintained and running in reserve to provide continuous, uninterrupted grid power.

As more intermittent or unpredictable energy is added to the grid, fast-reacting generation is required to provide continuous, reliable grid power. Utility companies and independent power producers must adequately balance renewable and traditional generation to maintain grid stability.

The renewable-based power systems designed, constructed and operated by WRH Power Systems use an Energy AI System™ with a cloud-based data repository to monitor and control the power system. The Energy AI System™ blends power flows from renewable sources such as solar, biomass and wind, coupled with battery storage and traditional thermal generation, to minimize power curtailment by commanding an optimal balance between power generation, energy storage, major grid assets, and where appropriate, imported grid energy costs and exported grid energy revenues.