Aeolian transport within a large-scale concentrated solar power plant in the Gobi region

Concentrated Solar Power (CSP) plants are typically located in gravelly desert (Gobi) regions because of their level, steady land, and abundant sunlight. The Gobi region has many sand sources, and strong winds accelerate aeolian processes, leading to windblown sand and dust at CSP sites. Large-scale CSP plant heliostats and central building clusters affect Gobi surface aerodynamic roughness and flow field characteristics, leading to a distinct aeolian transportation mechanism compared with that of a natural Gobi surface. Field observations from the 100 MW large-scale Gobi central-tower CSP facility in Dunhuang, China, were used to study a typical aeolian transportation event to gain insight into windblown sand and dust movement in CSP plants. The plant experienced a 36 % reduction in wind friction velocity owing to the increased aerodynamic roughness compared to that in the external environment. The facility reduces the minimum wind friction velocity for sand particle initiation to 0.37 m s−1, which is 30 % lower than that over the typical Gobi surfaces, however, sand accumulation between the heliostats resulted in a 1.8 times higher sediment transport quantity than that transported externally. The blown sand mean saltation layer height in the plant was 0.09 m, similar to that of a sandy desert. The plant surface emits dust, causing PM10 levels to increase to 20,000 μg m−3. Large-scale CSP facilities should remove sand build-up and use windblown sand management methods, such as checkerboard sand barriers and sand-blocking fences, to minimize aeolian transport and dust concerns.