As northern China slips into the winter chill, many residents may be unaware of the quiet shift in the energy sources now heating their homes.

Since November, centralized heating for 30 million square meters of indoor space in the city of Jinan, capital of east China's Shandong Province, has been powered by industrial waste heat recycled from two thermal power plants located more than 100 km away.

Designed with four relay pumping stations and pipelines, the hot steam generated by the power plants is pushed into the heating system in the urban area of Jinan.

By the end of this year, the new energy will supply heating for 100 million square meters of indoor space in Jinan. It is estimated that each heating season, the new energy can reduce the consumption of standard coal by 1.3 million tonnes and cut carbon dioxide emissions by 3.6 million tonnes.

Yu Changhao, deputy general manager of the production management department of Jinan Heating Group Co., Ltd., said that the company's smart dispatching center uses industrial internet and digital technology to enable an intelligent control of the pipelines.

In the command center, a large electronic screen displays tens of thousands of data points, including flow rate, pressure and temperature, updating in real time.

Based on weather forecasts, historical data and real-time feedback from the user end, the system predicts the heating load for the next 72 hours and automatically commands the pump station and valves to respond, Yu explained.

With the stable and clean heat source, the city is expected to phase out all of its 54 coal-fired boilers in the urban area within this year.

Meanwhile, the waste recycling will bring a guaranteed income of at least 500 million yuan (about 70.4 million U.S. dollars) to the power plants every year.

To ensure the smooth operation of the heat transmission artery, the heating operator in Jinan has built a hangar for unmanned aerial vehicles that are deployed to conduct air patrols of the pipelines.

The Central Meteorological Observatory on Sunday continued to issue blue alerts for cold waves and strong winds, forecasting that more than 10 provinces, autonomous regions and municipalities across the country will be affected. A powerful cold front is expected to bring a sharp drop in temperatures, with some areas seeing declines of more than 14 degrees Celsius.

As a result, freezing temperatures are expected to move southward to the provinces of Jiangsu, Anhui and Hubei on Tuesday.

The national capital, Beijing, began trial operations of its heating system on Nov. 6 in response to forecasts of rain and snow.

According to the Beijing Municipal Commission of Urban Management, the centralized heating area in Beijing's urban districts is expected to reach approximately 1.07 billion square meters during the 2025-2026 heating season.

As the world's second-largest city in terms of natural gas consumption, Beijing used 19.5 billion cubic meters in 2024, mainly for power generation and heating.

Yang Xiuling, director of the Beijing Municipal Development and Reform Commission, said that as the first city in China to fully achieve clean energy power generation, its coal consumption accounted for less than 1 percent of its total energy consumption in 2024.

The clean energy solution has contributed to improving the city's air quality. The annual average concentration of PM2.5 in Beijing has dropped from 89.5 micrograms per cubic meter in 2013 to 30.5 micrograms per cubic meter in 2024, a reduction of 65.9 percent.

The city has also promoted the use of electricity to replace coal for heating. By the end of October, the number of households using electricity instead of coal in Beijing had exceeded 1.37 million.

Elsewhere in the country, new technologies such as nuclear heating, biomass clean heating and air source heat pumps have been introduced to rural areas in large numbers to provide diversified clean heating solutions.

Yang Fuqiang, a researcher at the Institute of Energy of Peking University, said that the promotion of clean heating still faces challenges in areas with weak infrastructure, making it difficult to replace coal. By the end of 2024, the cumulative number of clean energy heating users in northern China had reached 41 million.

In the country's energy system, coal remains the "ballast stone." According to the latest data from the National Energy Administration, since October, the average daily coal dispatch output across the country has remained at a relatively high level of over 12.3 million tonnes. The coal supply is generally stable, and the inventory is abundant, providing a solid guarantee for energy use in winter.