Beihu Sewage Treatment Plant Distributed Photovoltaic Power Generation Project

The North Lake sewage Treatment Plant on the side of the North Lake in Wuhan is the largest urban sewage treatment plant built at one time in China, with an average daily treatment of 800,000 tons of domestic sewage. The subsidiary project of the plant was awarded the three-star green building operation mark.

Overlooking the North Lake sewage treatment plant from the air, 44,643 photovoltaic panels hang neatly above the plant like a jigsaw puzzle. Standing on the viewing platform of the North Lake sewage Treatment plant, looking out, the blue photovoltaic panels covering the entire plant shine in the sun. At this moment, light energy is silently converted into direct current energy, and "green energy" drives the factory sewage treatment operation.

"In November 2022, 44,884 photovoltaic panels of the North Lake sewage treatment plant will be connected to the grid at full capacity, with a total area of 185,000 square meters, equivalent to the size of 25 football fields, and is the largest distributed photovoltaic power generation project of the sewage treatment plant in China."

The North Lake sewage plant has a wide area, empty surroundings and sufficient light, and has the advantages of photovoltaic power generation. Photovoltaic power generation not only has no impact on production, but also shows some "secondary effects", such as the photovoltaic panel above the sedimentation tank blocks the direct sunlight, effectively inhibiting the growth of green algae in the pool, saving the number of cleaning.

There are many large treatment ponds in the North Lake sewage treatment plant, and the diameter of the secondary sedimentation tank alone is more than 50 meters. It is one of the construction difficulties to lay photovoltaic panels with large span of pool surface.

To this end, the project uses a combination of steel structure and prestressed steel cable system to obtain stiffness through the application of prestress to the steel cable, and through the longitudinal stability system to connect the lines into a whole, to jointly resist the impact of wind vibration. Among them, the single span of the cable in the secondary sedimentation tank area is 59.3 meters, which is the largest single span of the prestressed cable photovoltaic support system in the country at present.

The new installation method makes the construction cost 30% to 50% lower than the traditional steel structure support, the bearing capacity is increased by more than 30%, the construction period is shortened by 40% to 50%, the number of pipe piles is saved by more than 90%, the amount of steel is saved by 30% to 50%, and the building energy consumption is greatly reduced.

It is understood that the photovoltaic power generation operation period of the North Lake sewage treatment plant is 25 years, during this period, it can provide about 22 million KWH of green clean electricity per year, equivalent to saving about 8,000 tons of standard coal, equivalent to reducing about 20,000 tons of carbon dioxide, reducing about 70 tons of sulfur dioxide, reducing about 60 tons of nitrogen oxides, and reducing about 2 tons of dust.