Can Phase Change Energy Sorage Materials Make Buildings More Low-carbon?
2024-07-25
"Phase change energy storage is a new type of energy storage. As a class of efficient energy storage materials, phase change energy storage materials can not only reduce building energy consumption and improve indoor environmental comfort through the organic combination with buildings, but also make extensive use of renewable energy and improve the utilization rate of fossil energy. Li Haijian, director of the Phase Change Energy Storage Research Office of China Building Materials Research Institute and professor-level senior engineer, recently pointed out in an interview with a reporter from China Building Materials News that compared with other energy storage methods, phase change energy storage has the advantages of high energy storage density, small size, constant temperature control, significant energy-saving effect, wide range of phase change temperature selection, and easy control, and has important application value and broad development prospects in many fields. The calcium carbide slag component has good compatibility with Na2CO3, which can replace the traditional natural skeleton material to synthesize Na2CO3/calcium carbide slag composite phase change heat storage materials, and large-scale resource recycling of calcium carbide slag to realize the low-carbon and low-cost preparation of composite phase change heat storage materials.
The industry ushered in a golden period of development
"At present, the country vigorously advocates the use of clean energy and the promotion of low-energy buildings, which has ushered in a golden opportunity for the development of the phase change energy storage industry." Li Haijian pointed out that in advocating the use of clean energy and renewable energy, the country is stepping up efforts to control pollution in response to the increasingly serious problem of fossil pollution. Since 2015, the northern provinces have accelerated the implementation of coal-to-electricity projects in response to the problem of winter heating pollution. With the progress of these projects, the pollution problem of the northern heating season has been greatly solved, but there are still many problems. One of the problems is that after the coal to electricity, the heating cost of the people has risen sharply. In order to encourage the people to vigorously use cheap valley electricity, the relevant departments also stipulate that the use of energy storage electric heating must be used. This provides a great opportunity for the development of phase change materials.
In terms of building low-energy buildings, Li Haijian believes that low-energy buildings not only need to improve the insulation level, but also increase the energy storage capacity of the building. Now the building is mostly a concrete structure, compared with the old earthen wall building, the heat preservation and heat storage capacity is poor, resulting in colder in winter and hotter in summer, and the building thermal insulation is improved, the building has no storage capacity, loses the heat exchange with natural energy, and the free natural energy is wasted. To solve this problem, the heat storage capacity of the building should be improved.
"The current buildings are basically lightweight buildings, low thermal inertia, poor heat storage capacity, in order to improve the heat storage capacity of the building, it is impossible to adopt the earth wall like the old building in the past, the heat storage capacity of the building can be improved by adding phase change materials, the heat storage capacity of phase change materials is strong, the heat storage density per unit volume is high, and the heat storage requirements of the building can be met with less mass of phase change materials. The heat storage capacity of phase change building materials will show strong advantages, and phase change concrete, phase change mortar, phase change flooring, etc. will be vigorously developed. When talking about the development of the industry, Li Haijian said.
It can reduce the energy consumption of buildings
According to the reporter of China Building Materials News, there are two main ways for phase change energy storage materials to be used in buildings: one is "passive application". Phase change materials are compounded with traditional building materials to make phase change building materials, increase the thermal quality of the wall, and use as a "passive" energy storage material, relying on the change of room temperature or receiving solar radiation heat and other ways to passively absorb / release heat, the heat storage of the same volume phase change building materials is several times to dozens of times that of ordinary building materials, and the requirements of heat storage are realized without increasing the overall load-bearing of the building.
Phase change building materials mainly include phase change gypsum board, phase change concrete, phase change mortar, phase change coating, phase change wallboard, phase change energy storage floor or ceiling, etc. At present, phase change building materials have been widely used in building energy conservation and have good development prospects.
The other is "active application". Phase change materials are combined with solar heating, electric heating, floor heating, air conditioning, ventilation and refrigeration and other equipment to become an "active" energy storage body, which can be actively adjusted and controlled through heat exchange devices and heat exchange mediums, such as phase change heat collectors, phase change heat storage boxes, phase change heating systems, etc.
"Generally speaking, the slow development of phase change energy storage building materials or component products at home and abroad may be caused by the relatively high cost of phase change building materials and the low degree of integration with existing building design." Li Haijian introduced that relevant enterprises and research institutions at home and abroad are trying to promote the market-oriented development of phase change building materials, such as establishing calculation methods and standards related to existing energy-saving indicators to promote the development of the industry. In addition, phase change building materials enterprises can also start from the design of low-energy buildings, to overcome the integration of existing building design, such as the phase change materials made into phase change blankets, phase change tiles for the building envelope structure, the application form is flexible, the construction is fast and easy to recycle, the phase change materials are made into phase change bags, and then combined with the insulation board to prepare the phase change insulation integrated board, which is also a good innovation.
Li Haijian pointed out that in the heating and cooling industry, the development speed of phase change energy storage is relatively fast, there are already companies at home and abroad specializing in the operation of related markets, such companies are basically integrated with the existing basic business, their original business is mainly engaged in the heating or refrigeration industry, the addition of phase change energy storage elements can improve the efficiency of the original system, reduce the cost of system operation, especially the storage of renewable energy, the energy transfer of valley power, energy storage system has more advantages, As an efficient means of energy storage, phase change energy storage is increasingly favored by enterprises.
Future development needs to take multiple measures at the same time
"At this stage, the high cost of materials, long time limit for return on investment, and poor economics of building phase change energy storage products have become important factors restricting the further development and promotion of building energy storage." Li Haijian pointed out that there are still the following problems in the development of phase change energy storage materials: First, the standard system is not perfect. Standards are the basis for the industrialization of technology, and they are also an important factor to support the healthy development of the industry. Due to the lack of relevant technical standards, there are many limitations and inconveniences in the production and application of phase change energy storage materials, phase change building materials, and phase change device systems. Second, the national energy storage policy support is low. The development cycle of new technologies, especially new energy, is generally relatively long, and in the early stage of development, it usually needs the support of the country's industrial policy. Although the party and the state attach great importance to the development of the energy storage industry, the energy storage industry support policies are insufficient, and there is a lack of detailed implementation measures, such as technology development roadmap, industrial development guidance, relevant incentive policies, cost-benefit sharing and accounting methods, etc., and the development of the energy storage industry is relatively slow.
In order to achieve the high-quality development of phase change energy storage materials, Li Haijian suggested that the first is to formulate national phase change standards and engineering specifications to support the development of phase change energy storage materials. Formulate and publish technical standards, procedures, construction methods and general atlases of building energy storage (energy storage) technology and product equipment in a timely manner, strengthen the publicity, implementation and supervision of standards, and provide a strong scientific basis and solid technical support for standardizing and guiding the application of building energy storage (energy storage) technology. The second is to improve the key materials, manufacturing processes and energy conversion efficiency of building phase change energy storage, and further solve the problems of stability, safety and durability in large-scale applications. At present, most of the phase change energy storage technology is in the hands of scientific research institutes and university researchers, so as to improve the conversion rate of scientific research achievements, evaluate the practical application effect and long-term application efficiency, and provide monitoring data to improve the large-scale application demonstration.
This article was originally published in the 6th edition of China Building Materials News on December 19
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