Editor's note: Jan 26 is the International Day of Clean Energy and the founding day of the International Renewable Energy Agency. United Nations News spoke to Li Sheng, director-general of the China Renewable Energy Engineering Institute; Fang Li, country director of the World Resources Institute China; and Fu Yongfeng from the China Southern Power Grid on the development of clean energy in China. Below are excerpts of the interviews. The views don't necessarily represent those of China Daily.

As countries around the world accelerate their transition to green energy, research organizations such as the World Resources Institute play a vital role in building a bridge between scientific understanding and policy consensus. They also provide tools and methodologies to develop more consistent and mutually recognized standards, thereby minimizing the overall costs and supporting capacity building in different countries.

Organizations such as the China Renewable Energy Engineering Institute step in at this stage. Their task is to strengthen overall planning, prepare policy recommendations on energy development and provide credible research support. By doing so, they help Chinese energy enterprises expand overseas and support host governments in advancing the development of green and clean energy.

Enterprises can then take charge of operations, management and service delivery. Enterprises are indispensable not only as investors, but also as advocates of new development concepts and practitioners of service-oriented approaches. It is through their investment and implementation that more people can share the dividends of clean energy.

However, there are several challenges during implementation and operation. The first challenge is the structural tension within energy systems. Renewable energy sources such as wind and solar are inherently intermittent and volatile, with their output heavily influenced by weather and seasonal conditions. The existing power grids lack the flexibility and regulatory capacity required to fully accommodate large-scale and high-proportion integration of renewables.

At the same time, deep decarbonization on the consumption side remains particularly difficult. Some industries such as steel, cement and chemicals, as well as heavy transport, aviation and shipping, still rely heavily on fossil fuels. Alternative technologies are in the early stages of development and often come with high costs.

The second challenge concerns bottlenecks in key technologies and industry chains. While wind and solar technologies are relatively mature, frontier areas, including high-efficiency photovoltaic cells, long-duration energy storage, smart grid dispatch and the hydrogen industry chain, still face problems related to core materials, critical components and technological readiness.

The third challenge is financial pressure and economic viability. Clean energy projects typically require a large investment and have long payback periods. So, there is a strong demand for long-term, low-cost financing. However, against the backdrop of slowing global economic growth and rising interest rates, financing costs have increased while some developing countries face an acute shortage of capital.

As a result, countries differ significantly in their needs and capacities for clean energy development, making it difficult to mount a unified response to climate change. This underscores the importance of enhanced international cooperation, including closer collaboration with think tanks and financial institutions, to jointly address these issues and overcome shared challenges.

The green and low-carbon transition of the energy system is an irreversible global trend. Acting sooner rather than later is essential to seize this historic opportunity. Countries that hesitate risk falling behind the early movers.

The energy transition is not an option but a mandatory task tied to sustainable development. It should not be seen as a burden, but as a major opportunity to drive economic growth, improve people's well-being and enhance national competitiveness.

Clean energy means cleaner air, healthier lives and more job opportunities. It also means greater energy security through localized supply, stronger competitiveness for low-carbon products and new opportunities for countries to innovate together through cooperation.