The most efficient form of solar power is Concentrated Solar Power (CSP) which can reach an efficiency of up to 50%. The newest solar panels are less than half the efficiency, and it can be argued that growing of corn to create ethanol and fuel a power plant has a negative efficency.

What is CSP?

Concentrated Solar Power (CSP) is a technology that uses mirrors or lenses to concentrate sunlight onto a small area to generate high-temperature heat, which is then used to drive a thermal power plant. This technology can achieve efficiencies up to 50%, making it one of the most efficient forms of solar energy.

Where has CSP been used?

The Andasol solar power plant in Spain is one of the largest Concentrated Solar Power (CSP) plants in the world. It is located in Andalusia and has a capacity of 150 megawatts (MW).

The plant uses a combination of parabolic trough technology and thermal energy storage, allowing it to generate electricity even after the sun sets. The parabolic troughs concentrate the sun’s rays onto a fluid-filled pipe, heating the fluid to high temperatures. This thermal energy is then used to generate steam and drive a turbine, producing electricity.

Andasol has been operational since 2009 and has been contributing to Spain’s renewable energy mix, reducing the country’s dependence on fossil fuels and helping to mitigate climate change. The plant’s thermal storage system also helps to ensure stable and reliable power generation, even during cloudy periods.

Overall, Andasol is an important example of the potential of CSP technology in large-scale renewable energy generation and its positive impact on the environment and energy security.

How does Andasol store energy for night time?

Andasol has a thermal storage system, similar to how hot water is kept at the ready in your hot water heater tank. Excess heat absorbed by the Andasol plant solar field during the day is stored in a molten salt mixture of 60% sodium nitrate and 40% potassium nitrate. Scientists have calculated that this formula stores much more heat per volume than water. This storage allows Andasol to produce solar thermal power all day and all night.