Jiaxing completes China's first time-based carbon credit trade

The State Grid Jiaxing Power Supply Co (State Grid Jiaxing) has completed China's first carbon-inclusive asset transaction based on time-based electricity carbon factors, marking a new milestone in the application of carbon accounting to the country's low-carbon transition.

Using a refined carbon accounting system based on time-based electricity carbon factors, the company calculated carbon emission reductions generated by 24 public electric vehicle charging stations in Haining, a county-level city in Jiaxing, Zhejiang province. The project generated 43.25 metric tons of certified carbon dioxide equivalent (CO2e) emission reductions, which were subsequently traded through Jiaxing's carbon-inclusive market.

The transaction establishes a full process covering carbon reduction quantification, certification and market trading, providing a pathway for transforming verified emission reductions into tradable carbon assets.

As electric vehicle ownership continues to grow, many drivers have developed the habit of charging immediately after using their vehicles or after returning home from work. However, the carbon intensity of electricity varies throughout the day.

According to the company, a time-based electricity carbon factor measures the carbon intensity of electricity consumption at different times. During midday, when solar power generation is abundant, electricity carries a lower carbon intensity. In contrast, carbon emissions associated with electricity consumption are generally higher during evening peak hours, when thermal power accounts for a larger share of the electricity supply.

Based on this principle, the company developed a vehicle-to-grid carbon-inclusive accounting methodology that converts emission reductions achieved by charging during low-carbon periods into tradable carbon assets.

The approach enables electric vehicle owners who charge during periods of abundant renewable energy, such as around midday, to benefit not only from off-peak electricity prices, but also from measurable carbon reductions, making the environmental value of off-peak charging both quantifiable and tradable.

The certified emission reductions from the project have been purchased through Jiaxing's carbon-inclusive market by Zhejiang Dingchi Automotive Technology Co, based in Jianshan New District, Haining, and will be used in accordance with relevant regulations to offset a portion of the company's carbon emissions.

In the future, similar carbon credits could also be used to support carbon-neutral events, including the World Internet Conference Wuzhen Summit, as well as zero-carbon public institutions and voluntary carbon offsetting by businesses and individuals.

"I used to charge my car at midday mainly because electricity was cheaper," said Li, an electric vehicle owner charging at a public station near the Haining Sports Center. "Later, I learned that charging at the right time can also reduce carbon emissions. It saves money while helping protect the environment."

State Grid Jiaxing said it will continue expanding the use of time-based electricity carbon factors across a wider range of applications, encouraging greater participation from energy consumers in carbon accounting, and supporting the development of market-based mechanisms for carbon reduction.