Concentrating Solar Power


The Concentrated solar power (CSP) technology uses a system of mirrors or lenses, reflecting devices (parabolic mirrors) and solar tracking systems to concentrate a large area of sunlight onto a small focus point. In this small area, water or other liquids (oil, salt water) are heated by these concentrated solar radiations to reach high temperature. This is mainly used for large scale power generation or district heating (in cold climates).

The CSP technology is relevant for places where the direct normal irradiation (versus the diffuse irradiation) is significant, like Binh Phuoc or Ninh Thuan provinces for Vietnam, and when the land is available at a reasonable price and with limited conflict of land use.

In terms of technology, a CSP power plant is using different concentrating technologies:

  • Linear concentration system (Linear Fresnel Reflector, Parabolic Trough)
  • Focus concentration system (Central Receiver System, Parabolic Dish).

The final result of both methods is forming high pressure steam to drive the steam turbine for electricity generation.

(Source of picture: Artelia)

(Source of picture: Artelia)

As for solar PV farms, it can produce power from Solar Energy at large scale and at a competitive cost compared to traditional power plants. CSP does require a quite significant amount of water (for mirrors washing and sometime for the process).

A CSP plant can store the day time heat through a thermal storage (heat stored in high temperature water, oil or phase-change materials) and can produce power when there is limited or no sunlight (during nighttime or in bad weather conditions). Technology is available for peak or base load production. In addition, the overall yield of CSP is higher than solar PV (high output per MW installed).

Due to recent cut down of solar PV costs, the CSP tends to produce power at a higher cost compared to solar PV, through with notable advantages as cited above.

The CSP technology is seems by energy specialists as an alternative power production for Vietnam, producing large power at a competitive levelized energy cost compared to coal for instance (WWF, power vision for Vietnam, 2016).