Lishui city -- located in East China's Zhejiang province -- has abundant water resources and as a result, there are more than 800 small hydroelectric power stations throughout the city, with an installed capacity of 1.7 million kilowatts.

To cap it off, Lishui is the first prefecture-level city in China with an installed capacity of more than 1 million kW of hydroelectric power stations and has been honored as "the hometown of small hydropower in China".

Moreover, a virtual power plant which connects all the small hydropower stations in Lishui went  into operation this year, the equivalent to a large energy storage battery with a maximum adjustable capacity of 1 million kW, according to officials.

"The construction of a virtual power plant is to improve energy efficiency and help balance the supply and demand of the power grid in the province," said Wu Xiaogang, who is in charge of the new facility.

"The virtual power plant can easily achieve peak shaving without any cost or carbon emissions," Wu said.

On Jan 1 this year, as most factories in Zhejiang were shut down for the holidays, the electrical load of the province dropped by 23 percent compared to normal work days. However, photovoltaic power generation was still at a high level, leading to an imbalanced situation of supply exceeding demand.

The Zhejiang Power Grid remotely controlled Lishui's virtual power plant and achieved peak shaving -- the leveling out of peaks in electricity use by industrial and commercial power consumers -- of 430,000 kW. The move reduced electricity consumption by 94 tons of coal, equivalent to 253 tons of carbon dioxide.