Recently, the General Office of the State Council forwarded the "Action Plan to Accelerate Energy Conservation and Carbon Reduction in the Construction Sector" (Guo Ban Han [2024] No. 20, hereinafter referred to as the "Action Plan") issued by the National Development and Reform Commission and the Ministry of Housing and Urban-Rural Development, and made systematic arrangements for related work to accelerate energy conservation and carbon reduction in the construction sector. The "Action Plan" takes promoting low-carbon transformation of building energy consumption as one of its key tasks, and puts forward work requirements such as improving the level of building electrification, supporting the development of building photovoltaics, promoting the reduction of fossil energy heating in buildings, and promoting low-carbon transformation of rural energy consumption. This is an important measure to optimize the energy structure of buildings and effectively reduce carbon emissions in the construction sector, which will lay a solid foundation for actively and steadily advancing carbon peaking and carbon neutrality.

I. Upgrading the level of electrical technology in buildings

The "Program Proposal" proposes to improve the level of building electrification, promote the all-electric concept for newly built public buildings, and increase the popularization rate of electrification for residential heating, hot water, and cooking. This initiative would gradually reduce the consumption of fossil fuels in buildings and effectively improve the level of clean building energy use. At present, the penetration rate of natural gas for cooking, domestic hot water, and heating in urban buildings in China is relatively high. Hospitals, hotels, and other locations also use a certain amount of gas-fired or coal-fired steam boilers for disinfection and laundry purposes, and coal is still used for cooking and heating in some rural areas. Overall, there is great potential for electrification of building energy use. Various types of functional electric appliances, such as induction cookers, electric cookers, and electric water heaters, are readily available on the market and can basically meet the daily needs of households, hospitals, and restaurants. In addition, the current residential electricity prices in China are relatively low and have a price advantage compared to natural gas, so increasing the proportion of electricity used in buildings can also effectively reduce energy costs.

Positively support the integrated development of building photovoltaics

The "Action Plan" proposes to formulate and improve relevant standards and atlases on photovoltaic integration for building construction, carry out pilot projects on the construction of photovoltaic integration in new constructions such as industrial plants, public buildings, and residential constructions, and strengthen the management of the installation of photovoltaic systems in existing buildings. It is indispensable to have strong support from the construction sector to promote the clean, low-carbon, and efficient use of energy so as to speed up the planning and construction of a new energy system. At present, China's installed photovoltaic power generation capacity has exceeded 600 million kilowatts and will continue to grow rapidly in the future. It is estimated that photovoltaic installations can be installed in buildings and their surroundings in both urban and rural areas across the country, reaching 2.85 billion kilowatts, which can provide sufficient space resources for the installation of photovoltaic panels. In addition, the "Action Plan" also requires the promotion of efficient, flexible, and intelligent control technologies to promote the comprehensive participation of building complexes in response to electricity demand and peak regulation, which further increases the requirements for connection and consumption of photovoltaic power generation in buildings. Subsequently, by promoting the application of "light storage, direct and flexible", cold storage, heat storage, and flexible load regulation technologies, we can further explore building energy storage and flexible energy resources and promote the transformation of buildings from pure electricity consumers to electricity producers and consumers who have the functions of "generation, consumption, storage, and adjustment".

3. Promoting the gradual reduction of fossil energy heating in buildings

The Work Plan proposes promoting centralized heating with combined heat and power generation according to local circumstances, supporting the application of geothermal energy, biomass energy, and solar heating in buildings, and utilizing waste heat from thermal power plants, factories, and nuclear power plants. At present, the main heating sources in China's buildings include centralized combined heat and power plants, regional coal-fired or gas-fired boiler rooms, which generate a large amount of carbon dioxide emissions every year. Accelerating the optimization of the energy consumption structure of building heating, vigorously implementing the construction and renovation of supporting infrastructure, can effectively drive investment demand, and can also significantly reduce heating operation costs. For example, in low-density building areas with a building volume rate of less than 3, air source, ground source, and medium-deep geothermal source heat pumps can be given priority. If the building density is lower, solar photovoltaic energy can be fully utilized. In practice, some areas have started to use centralized or distributed air source, ground source, and water source heat pumps for building heating. In high-density building areas with a volume rate greater than 3, in order to meet the high heating demand, the full utilization of waste heat from nuclear power, thermal power, garbage incineration plants, and production processes in the metallurgical, chemical, non-ferrous, and building materials industries can be promoted after effectively solving problems such as efficient collection of heat, long-term efficient storage, long-distance and low-cost transmission, and transformation of heat parameters.

IV. Facilitate low-carbon transition in rural energy use

The "Work Plan" proposes to promote the low-carbon transformation of rural energy use, guide farmers to reduce the use of coal combustion, and encourage the use of electricity, natural gas and renewable energy according to local conditions. According to statistics, the installed potential of photovoltaic installations on the roofs of rural buildings and other facilities in China exceeds 1.9 billion kilowatts. In the future, more than 80% of rural areas will basically rely solely on the building's own photovoltaic power generation and surrounding hydropower to provide production and living energy. In addition, rural areas are also rich in biomass resources such as straw, branches, and livestock manure. More mature biomass fuel, biogas and other technologies can be used to convert them into zero-carbon fuels and enter the commercial fuel market. By implementing these measures, we can accelerate changes in rural energy use methods, transform rural areas from fossil energy consumers to important producers of low-carbon and zero-carbon energy, and effectively solve rural energy problems and environmental pollution problems. (Jiang Yi, academician of the Chinese Academy of Engineering and director of the Building Energy Conservation Research Center of Tsinghua University)