Qiao Liming, former head of Asia at the Global Wind Energy Council, said that while the law initially provided the framework and policy direction, it was the subsequent series of implementation rules that truly drove the market.

She pointed to the fixed feed-in tariff policy — borrowed from the German model — as the most critical element. "It allowed renewable power to be stably connected to the grid and sold, thus opening the door to the market," she said.

China's feed-in tariff mechanism — with classified price levels for different technologies and resource regions — requires grid operators to purchase renewable electricity at government-set prices, a guaranteed above-market rate funded through a small surcharge on electricity bills.

After six adjustments to subsidies for wind power and eight for solar, newly approved onshore wind and solar projects in China have achieved grid parity, with their on-grid tariffs set at the same level as local coal-fired power since 2021.

For the first decade after the law's enactment, China's wind power capacity grew 120-fold, from 1.26 million kilowatts to 150 million kW, while solar module prices fell to just one-tenth of their original cost.

However, as the industry expanded, challenges emerged. By the first half of 2016, the volume of curtailed wind and solar power had already surpassed the total for all of 2015. To address this, authorities replaced the full-guaranteed purchase mechanism with renewable portfolio standards in 2019, setting out binding targets for renewable consumption in each province.

In 2017, the Green Electricity Certificate was launched to provide a standardized way for businesses to track and verify that the power they consume comes from clean energy.

Dimitri de Boer, director for China at ClientEarth, an environmental law organization, noted that legislation must not remain static in order to be effective.

"Over time, the law, together with supporting policies, has gradually optimized the framework from administratively set prices, to competitive allocation, to full market integration and grid parity," he said.

De Boer said the second and current revision of the law provides an opportunity to further enhance its effectiveness in light of new and emerging trends.

He said further incentives for energy storage, demand-side response and flexible electricity pricing, for example, can help the energy system to adapt to the next stage of the energy transition, especially as China moves toward very high renewable penetration scenarios.

Equally, it's important to clarify the role of coal in the new system, repurposing it from base-load power to peaking power provision, he added.