What are the measures to achieve building carbon neutrality in the construction industry?

The construction industry is the main source of carbon emissions in China. According to the research, the carbon emission in the construction and operation stage is about 21.300 million tons, accounting for 2 1.6% of the national carbon emission. Under the goal of "double carbon", how can the construction industry get rid of the "high carbon" hat?

1, five paths: improving building energy efficiency standards, eliminating carbon emissions from building operation, reducing carbon emissions from building materials, optimizing and adjusting building streamline and functions, and using ultra-high energy-efficient equipment and energy substitution.

2. Implementation plan: reduce the cost of mature building technology, promote the application of new energy technologies, tap local low-carbon building materials, optimize the application of regional building energy, and strengthen the management of building information.

I have carefully selected 10 carbon neutrality depth data of the construction industry, including industry standards, assessment guidelines, PPT of experts and academicians, advanced cases, etc. You can use them in the article.

The construction industry is the "big family" of carbon emissions in China. The Research Report on Building Energy Consumption and Carbon Emissions in China (202 1) released by China Building Energy Conservation Association at the end of last year shows that the total carbon emissions in the whole building process in China in 20 19 was 4.997 billion tons of carbon dioxide, accounting for 50.6% of the national carbon emissions. Among them, the carbon emission in the construction and operation stage is 210.30 billion tons of carbon dioxide, accounting for 210.6% of the national carbon emission. Under the goal of "double carbon", how can the construction industry get rid of the "high carbon" hat?

0 1

Five ways to build carbon neutrality

1, improve building energy efficiency standards

From the end of 1970s, after more than 30 years' efforts, building energy efficiency in China has gone through five eras (as shown below).

According to the standards implemented at that time, the energy-saving effects of different buildings must be very different. In particular, one of the key points of energy-saving design standards is to improve the performance of the envelope to reduce the heat demand for heating in winter. Especially for residential buildings designed and built according to different standards in northern central heating areas, the difference in heating heat consumption can reach more than 3 times. Therefore, it is urgent to upgrade the existing stock buildings.

Source: Green Building Evaluation Criteria

There is a growing demand for building energy efficiency in China. At the same time, China is in line with international standards and has established a green building evaluation standard system with China characteristics and in line with China's national conditions. 20 19 released the new version of "Green Building Evaluation Standard", which has played a great role in promoting the development of green buildings in China to high quality.

2. Eliminate carbon emissions during the operation of buildings.

In addition to direct carbon emissions, indirect carbon emissions caused by building power supply and heating are the main part of building-related carbon emissions. Reducing these carbon emissions and further achieving zero carbon or carbon neutrality are the main tasks of building emission reduction and carbon neutrality.

Therefore, we must change the production mode of electricity and heat, and strive to achieve zero carbon or carbon neutrality in electricity and heat production. Nuclear power, hydropower, wind power, photoelectricity and biomass-based thermal power all belong to zero-carbon power.

If these power sources are used as the main power sources in China, supplemented by a small amount of coal-fired gas-fired power generation, and some carbon dioxide capture and storage technologies are used to recover the carbon dioxide emitted by coal-fired gas-fired thermal power plants, it is possible to achieve carbon neutrality in power production.

Source: Academician Jiang Yi: Peak CO2 emission and carbon neutrality of buildings in China.

In the report "The Path of Realizing Carbon Neutrality in Architecture" made by Academician Jiang Yi at the 20021Chengdu Green Building Conference, it was proposed that "light-storage elastic" buildings will become an important pillar for developing zero-carbon energy.

Based on China's natural conditions, under the background of developing a large proportion of wind power photovoltaic power supply structure in China in the future, in order to achieve carbon neutrality, the construction department should vigorously develop photovoltaic power generation on the surface of buildings, and at the same time let buildings absorb zero-carbon electricity from wind power photovoltaic bases in surrounding areas. The key to realize flexible consumption of renewable electricity in buildings is flexible electricity consumption, that is, "storing light directly and using electricity flexibly".

3. Reduce carbon emissions from building materials

At present, the completed area of urban housing and public buildings is maintained at 3-4 billion m2 every year, but the demolished building area is nearly 2 billion m2 every year. This shows that housing construction in China has changed from increasing housing supply to demolishing old buildings and building new ones to improve building performance and function.

"Demolition and construction" has become the main mode of the construction industry. Continued large-scale demolition and construction will continue to lead to strong demand for steel building materials, steel building materials production will continue to flourish, and the resulting carbon emissions will be difficult to come down.

Source: the realization path of carbon neutrality in the peak carbon dioxide emission in the construction field.

Therefore, changing the transformation and upgrading mode of existing buildings, from large-scale demolition to large-scale construction to maintenance and renovation, can greatly reduce the consumption of building materials, thus reducing carbon emissions in the production process of building materials. The construction industry should transform from building new houses to repairing old ones. This transformation will greatly reduce the demand for steel, cement and other building materials in housing construction, thus realizing the production reduction and transformation of these industries.

4. Optimize and adjust the building streamline and function.

From the demand side, priority should be given to reducing energy load, optimizing and adjusting building streamline and function, and adopting free measures such as natural lighting and natural ventilation as far as possible.

Secondly, building envelope structures with thermal performance more in line with climate characteristics can be adopted, such as external walls, doors and windows, roofs, sunshades, etc., to reduce the energy demand of buildings from the source. At the same time, the use of green, low-carbon and lightweight building materials can reduce the carbon emissions generated by building materials and construction waste.

5. Replace ultra-high energy efficiency equipment and energy.

Such as LED lamp, variable frequency water pump, magnetic suspension cooler, etc. And intelligent management means, such as intelligent charging piles and intelligent equipment start and stop. , improve energy efficiency and promote deep energy conservation and emission reduction. In addition, by strengthening the operation, debugging and operation management, avoiding technical piling, and taking the result as the guide, the ultra-low energy consumption building can be realized.

Source: the realization path of carbon neutrality in the peak carbon dioxide emission in the construction field.

Through building photovoltaic integration (BIPV), energy storage (battery energy storage, ice storage, phase change materials, etc. ), ground source water source heat pump, biomass power generation, absorption heat pump and other technologies can make full use of local renewable energy and waste heat and cold energy to replace fossil energy and reduce carbon emissions.

02

Building carbon neutral implementation scheme

1, reducing the cost of mature construction technology.

High-performance building envelope is a mature key technology to reduce building energy demand from the source. However, China's high-performance doors, windows and exterior walls have long relied on foreign imports, and the cost is high. By means of technology introduction, industrial localization and engineering practice innovation, the cost of mature technologies such as high-performance envelope can be greatly reduced, which is the key direction to achieve carbon neutrality in the construction field.

2. Promote the application of new energy technologies.

Source: BIPV technology white paper

Building Photovoltaic Integration (BIPV), energy storage and intelligent charging are emerging technologies to achieve building carbon neutrality. From the aspects of product design, technical performance and economy, these emerging technologies are still immature and still need strong support from policies and markets. The large-scale popularization and utilization of new technologies conducive to building carbon neutrality will expand the technical options of building carbon neutrality and accelerate the early realization of building carbon neutrality.

3. Excavate local low-carbon building materials

In recent years, developed countries in Europe and America, which are rich in wood resources, have begun to explore green and low-carbon building materials such as pure wood structures and accumulated a lot of technical experience. However, due to the shortage of wood in China, it is not suitable to take the technical route of pure wood structure. Instead, we should try to explore green, low-carbon and recyclable building materials such as bamboo and rammed earth according to local conditions, strengthen the modernization of traditional technology, and combine assembly technology to promote the green and low-carbon development of building materials in China and make contributions to the realization of carbon neutrality in the whole life cycle of buildings.

4. Optimize the application of regional building energy.

In areas like Central Business District (CBD), tourist resorts, innovative industrial parks, etc., the demand for building cooling, heating and electricity is large, and using traditional energy supply methods will consume a lot of primary energy. According to the local resource conditions, renewable energy technologies such as ground source heat pump, water source heat pump and distributed photovoltaic are reasonably adopted to meet the regional energy demand.

5. Strengthen the information management of buildings.

Source: the path of emission reduction in construction industry and the enlightenment of scientific and technological innovation

The informatization level of the construction industry has lagged behind other industries for a long time, and the realization of building carbon neutrality depends on the improvement of building informatization technology, building energy consumption simulation technology and building intelligent management technology. Promote the standardized and intelligent management of the construction industry through building informatization, improve the overall efficiency of the construction industry, and track and effectively manage building carbon emissions in real time.