What does a building look like with zero energy consumption, zero carbon emissions, and a comprehensive energy-saving rate of 100%?

Source: Xinhua Daily

Recently, the East China (Nanjing) Agricultural Science and Technology Innovation Port project located in Lishui District is stepping up its construction recently. One of the buildings comprehensively uses photovoltaic panels, geothermal heat pump and other technologies to "add and subtract" energy consumption through energy substitution and other ways. It is designed and built according to the comprehensive energy saving rate of 100% to achieve "zero carbon" emissions in the operation phase.

To achieve "zero carbon", focusing on passive design and reducing energy consumption is the first step. Passive technology is a low-carbon technology that utilizes climate characteristics and natural conditions to provide a comfortable indoor environment with less energy consumption. The building adopts a high-performance modular skylight system to meet environmental requirements such as lighting, ventilation, shading, and insulation.

This building is designed with a atrium skylight that can be opened to facilitate natural ventilation and lighting. The high-performance enclosure structure can provide insulation and reduce heat loss, "said the project site leader.

The "cloud like" roof is actually a "green power plant". The building comprehensively uses photovoltaic integration and geothermal heat pump technology to improve the utilization rate of renewable energy of the building itself. Photovoltaic integration can convert solar energy on the roof into electric energy and continue to supply power for the building.

The geothermal heat pump system can provide cooling and heating for buildings and reduce the power consumption during the operation of air conditioning. The underground design of the building has a buried pipe depth of 120 meters and a COP value of 6.16. "With this geothermal heat pump, one share of electricity can be exchanged for 6.16 shares of cooling capacity," said the person in charge of the site.

In the project control center, indoor temperature, humidity, carbon dioxide, and PM2.5 are monitored in real-time, and building energy consumption is clear at a glance. The project designs an intelligent lighting system and air quality monitoring system, which are linked and controlled with the fresh air system. Through intelligent management, operational efficiency is improved.

The fresh air unit is equipped with a total heat recovery section, with a total heat exchange efficiency exceeding 60%. Small spaces such as offices and meeting rooms use fan coil units with fresh air, while large spaces use full air systems. It is reported that the fresh air function is combined with central air conditioning to ensure fresh indoor air while also achieving energy-saving effects.

Actively use green building materials, prioritize the use of recyclable materials for interior decoration, and reduce resource waste from the source. The park design uses modular prefabricated planting containers, which can store natural precipitation and supply irrigation plants, promoting rainwater recycling and utilization.

The main body of the building adopts a recyclable steel frame structure system, with steel beams, steel columns, etc. The proportion of high-strength steel used reaches 90%. Steel structural components are manufactured in factories and assembled on construction sites, with a high degree of standardization and industrialization. There are fewer welding operations on construction sites, which can save a lot of time and cost.

The project is designed with a multi-dimensional and composite landscape greening, utilizing the gray space on the roof to add green plants and setting up an observation platform. It not only combines with leisure areas and rooftop photovoltaics to form a landscape decoration on the fifth facade, but also absorbs carbon dioxide, reduces greenhouse gases, and increases carbon sequestration.

According to calculations, the existing green area of the site is about 800 square meters, with a carbon sink of 0.42 tons. The roof green area is about 1500 square meters, with a carbon sink increment of 0.78 tons. The entire building can increase its "carbon storage" by 1.2 tons per year. To promote the realization of carbon peak and carbon neutrality, high-quality green buildings that focus on near zero energy consumption like the innovation port project will become the trend of future construction industry development. In addition, projects such as the industrialization of new buildings and the application of renewable energy buildings will also be launched simultaneously to jointly promote the high-quality development of the construction industry.