SHANGHAI, July 4 (Xinhua) -- At a fish farm on Hengsha Island, Shanghai, a fisherman is tending to his fishpond shaded by photovoltaic panels, scooping out a sprinkling of duckweed on the surface of the water into a bucketcastlemachinerycrashbandicoot.

While the practice of integrating fish farming with photovoltaic (PV) power generation has continued to benefit this small island situated at the easternmost tip of the Yangtze River's mouth, more green electricity innovations have propelled the island's zero-carbon transitions.

Hengsha Island, boasting sufficient sunlight and wind resources, witnessed a 3.5 megawatt PV power generation project installed on the island and operated at the end of 2012 as one of Shanghai's first fishery-PV complementary projects.

The PV station was built over a fishpond, with PV panels mounted three meters above water. It generates electricity while also providing shelter for shade-loving fish and pasture grass underneath.

During its 25-year service life, the station is expected to generate over 3.86 million kilowatt-hours of electricity annually, saving 1,179.3 tonnes of standard coal per year, equivalent to reducing 3,857 tonnes of carbon dioxide and 116 tonnes of sulfur dioxide annually.

Moreover, fish farming has generated financial rewards for residents. Shi Weizhong, 60, owner of a farm-stay business, adopted the fishery-PV complementary concept for the fishpond on his farm. He expected the output value of fish farming alone to reach 50,000 (about 7,011.4 U.S. dollars) to 70,000 yuan this year.

In addition to the fishery-PV complementary project, Hengsha Island has also promoted distributed photovoltaic power generation projects by assembling rooftop PV panels and integrating PV power generation with power storage and charging.

Yang Zhengbang, hailing from Xinchun Village of Hengsha Island, installed 60 solar PV panels on his home's rooftop in 2018. In 2023, Yang's PV panels were upgraded into an integrated system that included batteries to store surplus electricity generated during the day and to power Yang's house at night. A car charging pile was also incorporated into the system.

"After installing PV panels, I felt satisfied with the savings on my electricity bill, and now I save even more with energy storage and charging incorporated into the system," Yang said, "All in all, I save about 300 yuan a month."

According to Zhang Weiyang, a staff member at the State Grid Shanghai Changxing Power Supply Company, the integrated system running in Yang's house prevents emissions of 24.96 tonnes of carbon dioxide every month.

The leading role of Hengsha Island in the green electricity endeavor offers a glimpse into Shanghai's green development initiative, exemplified by the surge in transaction volume of green electricity certificates.

From January to early June, over 15 million green electricity certificates were transacted, a steep rise from the annual transaction volume of 460,000 in 2023.

The trading of green electricity certificates, proof of electricity generated from renewable energy sources, offers enterprises opportunities to reach energy conservation and emission reduction targets while promoting renewable energy consumption.

Shanghai has envisioned that by 2025, the transaction volume of green electricity will exceed 5 billion kilowatt-hours.■