Integrated project crucial in green power leap

China's largest integrated wind-solar-storage demonstration project will play a key role in fully taking advantage of the green power produced locally while meeting the electricity needs of large enterprises, industry experts said.

The project, designed and built by China Three Gorges Corp in Ulaanqab, North China's Inner Mongolia autonomous region, has a total installed capacity of 2 gigawatts and was put into operation recently.

Equipped with a 220-kilovolt grid connection project, the project marks a significant milestone as the first energy station in China with a storage capacity exceeding 1 gigawatt-hour, elevating the integration level of renewable energy and enhancing the comprehensive utilization of electricity, it said.

The project is expected to produce a total energy of 6,300 GWh each year. Annually, this output is expected to save about 2.03 million metric tons of coal, curtailing carbon emissions by around 5.2 million tons, marking a major stride in sustainable energy development, said the company.

As demand for clean, renewable energy sources surges, there is growing consensus among industry experts that energy storage will play a pivotal role in driving green transition forward in China.

Energy storage utilities of the Ulaanqab project can provide massive benefits for local grid operation by taking in excess power from renewables when demand spikes, enabling renewable facilities to function more like traditional power plants.

The discharge of electricity from batteries when renewable power resources are not reliable due to special weather also provides an attractive degree of flexibility for grid operators who have to match electricity supply and demand in real time.

With the commissioning of numerous gigawatt-scale renewable base projects in Northwest China, the local grid system needs to integrate renewable capacity, optimize power output and address intermittency issues brought on by wind and solar energy, said Deng Simeng, a senior analyst in renewables and power research at global consultancy Rystad Energy.

"Battery storage, which entails smaller devices, flexible sites, and shorter construction periods compared with wind, solar and other conventional power sources, is gathering significant attention for its pivotal role and benefits," she said.

"In terms of application, battery storage, with advantages in peak shaving, frequency regulation, fast response, and flexible dispatch, not only assists wind and solar farms on the generation side, but also supports grid-side and user-side operations."

According to Deng, by the end of 2023, Northwest China had installed 222 GW of wind and solar capacity, and over 10 GW of battery storage projects.

Given the rapid pace of renewable installations, accelerating the development of new-type energy storage will be a key breakthrough for the region to mitigate renewable curtailment and enable a more resilient and secure power grid.

According to Du Zhongming, president of the China Electric Power Planning and Engineering Institute, the development and transmission of large-scale new energy bases has necessitated higher requirements for transmission technology, while the flexible adjustment of the load side in the country has not been fully developed.

Through the large-scale application of energy storage, the power system will shift from traditional power supply with load mobilization to the integration of source, grid, load and storage, making new energy storage the key to building a new power system, he said.

Battery storage, seen as the "backbone of reliability" planning in places like Inner Mongolia, is growing in the country with many regions boasting rich renewable energy resources building large-scale battery storage projects in recent years.

Since 2020, Inner Mongolia has been actively promoting the integration of source, grid, load, and storage. Currently, two projects have been approved, with one project in the application process.