Original title: Can "central cooling" be promoted vigorously?
Central cooling and heating has the characteristics of intensive land use, peak shifting and capacity reduction, high efficiency and energy saving, intelligent management and control, and avoiding repeated investment. It is especially suitable for promotion and application in areas with high density of commercial buildings such as urban CBD.
It should be pointed out that this model is not suitable for all energy use scenarios, and its popularization and application should also be scientifically demonstrated and systematically designed.
Everyone knows about "central heating", but have you heard of "central cooling"?
Recently, the topic of "centralized cooling" in Jinan, Shandong has attracted attention.
Wang Chenfu, deputy director of the Jinan Central Business District (Jinan CBD) Management Committee, told reporters that starting from this year, the district has been running a trial operation of the central cooling mode, which has now covered nearly 21 public construction users such as office buildings, hotels, and commercial complexes in the district. Ten thousand square meters.
The whole project adopts the same set of municipal pipe network, which provides heating in winter and cooling in summer.
"The indoor temperature is kept at about 26°C, and the effect is very good. The cooling cost is settled according to the amount of cooling used, and the meter is measured. If you don't use it, there is no cost, which saves you worry and money." Shandong Port Logistics Group Hotel, which works in the CBD area Zhang Zihao, general manager of the management company, said.
Central cooling can also manually adjust the temperature.
According to reports, the cooling facilities at the end of users in Jinan CBD area are all in the form of fan coil units. This kind of equipment has its own temperature control panel, and users can adjust the indoor temperature according to their needs.
Cui Yue, Secretary of the Party Branch, Chairman and General Manager of Shandong Ruiguan Electric Power Co., Ltd. of Jinan Energy Investment Group, a subsidiary of Jinan Energy Group, introduced that the same set of transmission and distribution pipelines are used for central cooling in summer and central heating in winter, but they are switched to cold sources. , the chilled water at about 7 degrees Celsius is transported as a refrigerant to the cooling station at the same location as the heat exchange station for heating in winter.
Through the principle of cold exchange, the chilled water of about 7 degrees Celsius to 9 degrees Celsius is replaced, and it enters the end air disk system of the user to meet the cooling demand in summer.
Zhang Xueqian, deputy secretary of the party committee and general manager of Jinan Energy Investment Group, told reporters that in May 2017, the Shandong Provincial Government and the Jinan Municipal Government invited a number of urban planning companies at home and abroad to participate in the planning and design of Jinan CBD, and compiled the "Jinan CBD Urban Design and Guidance". Regulations", which stipulates that the district will adopt regional central cooling on the basis of the original central heating in Jinan City.
"The building type of Jinan CBD is suitable for district cooling." Zhang Xueqian told reporters that when Jinan CBD was urban planning, it was clear that this area was a commercial agglomeration area. Important prerequisites for the development of district energy projects.
What are the advantages of central cooling?
Li Gang, chief engineer of Tongyuan Design Group, who participated in the demonstration of the central cooling scheme in the early stage, introduced that the regional central cooling and heating has the characteristics of intensive land use, staggered peak capacity reduction, high efficiency and energy saving, intelligent management and control, and effective avoidance of repeated investment, which is especially suitable for urban CBD. It is popularized and applied in high-density and concentrated areas such as commercial buildings.
This model can take advantage of the different characteristics of commercial buildings with different functions at peak times of energy demand, and through reasonable design, while reducing the total installed capacity, it can improve system economy and ensure safety and stability.
In addition, with the design of ice storage and water storage systems, peak-to-valley electricity price difference can be fully utilized for cooling storage and peak regulation, which not only reduces the operating cost of the system, but also realizes peak shaving and valley filling of the power grid.
"Analysis of actual operation data shows that for super high-rise buildings over 200 meters, the construction and use cost of central cooling is lower than the cost of separate air-conditioning units in the building; for general commercial buildings, the construction and use costs of the two are equivalent." Li Gang According to the introduction, for buildings with high building density and high cooling demand, due to the large-scale advanced and high-efficiency chillers used in central cooling, the cooling energy efficiency is much higher than that of ordinary air conditioners. The cost is lower than the individual air conditioning system in each building.
However, for low-density commercial buildings or areas with irregular energy demand, the building independent air conditioning system is relatively flexible, and its construction and use costs are generally lower than central cooling.
According to reports, the district cooling technology has been valued by many countries because of its high efficiency and low impact on the environment.
Some commercial gathering areas in Europe, commercial buildings in some big cities in Japan, and many university campuses in the United States all adopt this method of district cooling.
Areas such as Guangzhou University Town, Shenzhen Qianhai, Shanghai Hongqiao, and Beijing Zhongguancun Science and Technology Park have also adopted the district cooling method and have been put into operation.
Can central cooling be promoted vigorously?
"This model is not suitable for all energy use scenarios, and its promotion and application should also be scientifically demonstrated and systematically designed." Li Gang believes that which cooling and heating model should be selected, first of all, reasonable regional energy planning should be carried out, and scientific research from the demand side should be carried out. Analyze the energy use characteristics and system applicability of the project, and carry out overall planning and overall calculation through load simulation, digital twinning and other means; secondly, the energy efficiency of equipment should be improved as much as possible, unnecessary transmission and distribution losses should be reduced, and renewable energy should be used according to local conditions. The intelligent level of operation management; finally, the system equipment procurement and installation and load requirements should be coordinated, and the coordination and adaptation should be gradually improved to avoid premature and large capital investment.
"Only through scientific planning, fine design, overall coordination, and intelligent operation and maintenance can we give full play to the advantages of regional central cooling and heating, and achieve the goals of low-carbon energy saving, green environmental protection, and safety and economy." Li Gang said.
Wang Jinhu