About Solar Energy

Solar energy: As the expression suggests, solar energy is the light and heat irradiated from the Sun and captured with the use of different technologies such as, photovoltaics, solar thermal energy for heating and, in the case of the CAPTure project, concentrated solar power (CSP). Solar energy is one of the most relevant sources of renewable energy.

Renewable energy is generally known as a type of energy that is captured from resources that can be naturally regenerated in a considerable short time period. The common examples are solar energy, wind, tides, waves, geothermal, biomass and hydro power. Renewable energy can provide energy to respond to the world needs for electricity, heating & cooling and transportation.

Solar power stands for the conversion of sunlight into electricity, which can happen both in a direct way, as in the case of photovoltaics (PV), or indirectly using concentrated solar power (CSP).

Concentrated solar power or solar thermal electricity systems use lenses or mirrors (heliostats) and tracking systems to reflect the sunlight irradiated in a large area onto a small focus point. In this case, electricity is generated by the concentrated light being converted to heat. This conversion drives a heat engine connected to an electrical power generator. Concentrated solar power should not be confused with concentrator photovoltaics (CPV). In CPV, the concentrated sunlight is converted directly to electricity via the photovoltaic effect. The CAPTure project intends to increase concentrated solar power plant efficiencies and reduce levelized cost of electricity (LCOE) from concentrated solar power by, developing all relevant components that allow implementing an innovative plant configuration. The plant configuration is based on a multi-tower decoupled advanced solar combined cycle approach, seen on figure 1.

Figure 1

Figure 1: The CAPTure plant configuration is based on a multi-tower decoupled advanced solar combined cycle approach

 

The Brayton cycle is a thermodynamic cycle that describes the workings of a constant pressure heat engine. The original Brayton engines used a piston compressor / expander Gas turbine engines and airbreathing jet engines use the Brayton cycle.

The Rankine cycle closely describes the process by which steam-operated heat engines commonly found in thermal power generation plants generate power. The heat sources used in these power plants are usually nuclear fission or the combustion of fossil fuels such as coal, natural gas, and oil.

Heliostat is a device that uses a mirror and turns with the aim to keep reflecting sunlight toward a predetermined spot. CAPTure is developing the following low-cost heliostat.

Low-cost heliostat

 

A solar furnace is a structure that uses concentrated solar power to produce high temperatures, usually for industry. In a concentrated solar power plant, the heliostats reflect the light towards the solar furnace. In the CAPTure project, the devices will be tested at the Solar Platform in Almeria, Spain.

Plataform Solar de Almeria