Energy Change Promotes 'Smart' Green Building Salon Held Online

Building carbon emissions accounting method:

The entire life cycle of a building, from the transportation of building materials, to the construction process, to building operation, and finally to building maintenance and scrapping, will generate carbon emissions in every link. Among them, the carbon emissions from the production and transportation of building materials are called the embodied carbon emissions of building structures, which belong to the carbon emissions that have been included in the industrial production process, and only need to discuss its impact on the industry. Therefore, when discussing carbon emissions related to the construction sector, we pay more attention to the direct carbon emissions caused by the use of fossil fuels in buildings generated by building operations, and the indirect carbon emissions generated by building heat, electricity, and steam.

Based on these emission sources, Academician Jiang proposed that we can comprehensively reduce emissions in the construction sector through the following methods:

Reduce the embodied carbon emissions of building structures:

China is in the stage of urbanization and infrastructure development, and the carbon emissions caused by the production, transportation and construction of building materials related to construction and infrastructure construction have reached 4.05 billion tons. At the same time, the per capita total of urban and rural buildings in my country will soon reach 55m2, surpassing Japan and South Korea.

In the case of a shortage of land and resources, China can avoid large-scale demolition and construction, and shift the focus of construction from new construction to maintenance and function improvement. At the same time, it will develop low-carbon building life extension and function improvement technologies to achieve a strategic shift in the construction field and to achiece emission reduction.

Reducing carbon emissions from building operations:

Fully electrified and no longer use any fossil fuels in the building to eliminate direct carbon emissions. However, the energy composition of grid power generation is dynamic, so every moment, the carbon emission responsibility corresponding to each kilowatt-hour of electricity used by the demand side is different. If the demand side has sufficient energy storage and flexible regulation of power consumption, you can choose to use more electricity and store electricity when the carbon emission factor corresponding to electricity is low, and reduce electricity from the grid when the carbon emission factor of electricity is high. Use energy storage to meet electricity demand. This can not only reduce the indirect carbon emissions caused by electricity consumption in building operation, but also solve the problem of wind power and photovoltaic variability by using the power terminal with the new power system. 

Helping zero-carbon electricity: Assisting in the construction of a new type of power system with the goal of zero carbon. The full electrification of buildings requires the promotion of zero carbonization of electricity consumption in buildings. Installing photovoltaic power generation on the roof of rural buildings can be a better measure to achieve this goal, because it can solve 85% of rural energy consumption in the country, and even send more than 1 trillion kWh of electricity to the grid every year according to dispatch, realizing a new rural energy system. 

At the same time, in cities, urban buildings can link private electric vehicles and intelligent two-way adjustable charging piles to realize photovoltaic power generation, energy storage, DC power distribution, flexible loads, effectively absorb wind power and photovoltaics, and finally realize zero-carbon power operation of buildings.

Develop zero-carbon heat sources to meet the heating needs of northern buildings in winter. A large-scale cross-seasonal heat storage system can be built to provide zero-carbon heat sources for urban heating to meet winter heating demand, such as a large-scale cross-seasonal heat storage system, making full use of waste heat in the production process of nuclear power, metallurgical and non-ferrous chemical building materials.

Finally, even with these emission reduction measures, building energy efficiency is still the basis for emission reduction. It is necessary to avoid a large increase in energy consumption on the demand side as income increases. Building energy efficiency can improve energy efficiency through the development of innovative energy-saving technologies , Adhere to the green way of life and other ways to achieve.

Original CEMF Tsinghua University CIDEG 2022-09-07 17:40 Posted on Beijing