"At the end of last year, we replaced all our windows, switching from single-glazed to double-glazed, and the temperature in our home immediately rose by three to four degrees Celsius. Now that the walls and roof have all been renovated, our home will certainly be even warmer this winter," said 77-year-old Zhou Xuying, who has lived with her husband in Jinzeyuan Residential Community in Taiyuan, Shanxi Province for 21 years. She and her old neighbors all believe that the energy-saving renovation of old residential communities is a great service the government has rendered to the people.

Jinzeyuan Residential Community was built in 2000 and has 11 residential buildings. Zhou Xuying said that before the renovation, many walls in the buildings here had cracks, and in some places even the rebar was exposed. In winter, indoor temperatures were often only 16 to 17 degrees Celsius.

On August 31, the largest energy-saving renovation project for old residential communities in Taiyuan, Shanxi, was completed. As a demonstration project in building energy efficiency and green buildings in Shanxi Province, it is characterized by its large scale, long time span, and large affected population. The renovation covered 2,337 buildings in 652 communities across 6 urban districts of Taiyuan, spanning buildings constructed between 1966 and 2006, with a total floor area of about 10.02 million square meters, bringing a more comfortable and energy-efficient living environment to more than 180,000 households.

Old residential communities commonly suffer from aging infrastructure, damaged exterior facades, and interiors that are cold in winter and hot in summer. Such living conditions not only affect residents' quality of life but also consume more energy.

This large-scale energy-saving renovation of old residential communities made bold innovations in its model, introducing social capital, with China Railway 12th Bureau Group leading the construction. In addition to renovating the buildings' appearance, the project also carried out substantive energy-saving renovations inside the buildings, replacing single-glazed windows with double-glazed ones, adding wall insulation layers, and installing waterproof and insulation layers on roofs.

At the entrance of Changsheng Garden Community in Taiyuan, the construction contractor displayed samples of the exterior wall construction techniques to residents. Project manager Yang Pengyu told reporters: "Exterior wall construction includes the insulation layer, plastering layer, finish layer, and so on. We publicly display the construction materials and methods for each layer to residents and invite them to supervise." Zhang Jinsheng, project manager of the energy-saving renovation for China Railway 12th Bureau Group, said that after renovation, the energy consumption of old buildings was reduced by 75%. With less use of air conditioning at home, residents can save on electricity bills.

The building sector is a major energy consumer and carbon emitter in China, and the energy-saving renovation of existing residential buildings is an important part of achieving the "dual carbon" goals. As a national pilot for comprehensive energy revolution reform, Shanxi's energy-saving renovation of existing residential buildings is also a measure to implement the "clean, efficient, green and low-carbon" approach. According to reports, after renovation, the average indoor temperature of old residential communities in winter increased by 3 to 4 degrees Celsius, and in summer the indoor temperature can be lowered by 2 to 3 degrees Celsius, equivalent to an annual reduction of 193,500 tons of raw coal burned during the heating season.

Wang Yanzheng, deputy director of the Taiyuan Green Building and Sponge City Development Center, said that the renovation of old residential communities is a major livelihood project in Taiyuan and is of great significance to improving urban quality and promoting the city's green transformation. After renovation, indoor comfort in the old residential communities has improved markedly, and the community environment has been enhanced. The project has become a heartwarming project that resonates with the people.