The integrated energy system refers to the use of advanced physical information technology and innovative management models in a certain area to integrate various energy sources such as coal, oil, natural gas, electric energy, and thermal energy in a certain area to achieve coordinated planning among various heterogeneous energy subsystems. Optimize operation, collaborative management, interactive response and mutual assistance. While meeting the diversified energy demands within the system, it is necessary to effectively improve energy utilization efficiency and promote a new integrated energy system for sustainable energy development.
1. Basic concept of integrated energy system
Theoretically speaking, the integrated energy system is not a new concept, because in the energy field, there has been a long-term collaborative optimization of different energy forms, such as CCHP generator sets through the coordinated optimization of high and low grade thermal energy and electric energy to improve fuel utilization efficiency The purpose of ice storage equipment is to coordinate electric energy and cold energy (which can also be regarded as a kind of thermal energy) to achieve the purpose of peak-shaving and valley-filling of electric energy. Essentially, both CCHP and ice storage equipment belong to local comprehensive energy systems. In fact, the concept of an integrated energy system originated from the research in the field of thermoelectric co-optimization.
The integrated energy system specifically refers to the integration of energy production, supply and marketing formed after the organic coordination and optimization of energy generation, transmission and distribution (energy network), conversion, storage, and consumption in the process of planning, construction, and operation. system. It mainly consists of energy supply network (such as power supply, gas supply, cooling/heating network), energy exchange links (such as CCHP units, generator sets, boilers, air conditioners, heat pumps, etc.), energy storage links (electricity storage, gas storage, heat storage, cold storage, etc.), terminal comprehensive energy supply units (such as microgrids) and a large number of end users.
2. National research on integrated energy systems
The United States proposed a comprehensive energy system development plan in 2001, with the goal of promoting the promotion and application of distributed energy resources (DER) and combined heat and power (Combined Heating and Power, CHP) technologies and increasing the proportion of clean energy usage. In 2007, the United States promulgated the Energy Independence and Security Act, requiring comprehensive energy planning in the main energy supply and use links of the society in the form of legislation; and with the continuous increase in the proportion of natural gas usage, for example, after 2011, more than 25% of the energy consumption in the United States comes from natural gas , the US Natural Science Foundation, the Department of Energy and other institutions set up a number of projects to study the coupling relationship between natural gas and power systems. The vision of the national smart grid strategy promoted by President Obama is to build a high-efficiency, low-investment, safe, reliable, intelligent and flexible comprehensive energy network, and the intelligent power network plays a central role in it.
Canada regards the integrated energy system as an important supporting technology to achieve its 2050 emission reduction target, and focuses on the research and construction of the community-level integrated energy system (Integrated Community Energy System, ICES). Several bills were enacted to facilitate ICES research, demonstration, and construction.
Europe also carried out research on integrated energy systems very early and put them into practice first. Through the EU framework projects, European countries have carried out fruitful research work in this field. In addition to promoting research in this field under the overall framework of the European Union, European countries have also carried out some characteristic research according to their own needs. Taking the UK as an example, the British Engineering and Physical Sciences Research Society has funded a large number of research projects in this field, involving renewable energy grid connection, synergy between different energy sources, interaction between energy and transportation systems and infrastructure, and building energy efficiency improvement. .
Due to its heavy dependence on imports of energy, Japan has become the first Asian country to carry out research on integrated energy systems, and hopes to ease the pressure on its energy supply through technological innovation and progress in this field. Under the vigorous promotion of the government, all walks of life in Japan have carried out extensive research on integrated energy systems from different aspects.
my country has launched many scientific and technological research and development projects related to integrated energy systems through the 973 Program, 863 Program, National Natural Science Foundation of China and other research programs, and has carried out many international cooperation in this field with Singapore, Germany, the United Kingdom and other countries. The content involves many aspects such as basic theory, key technology, core equipment and engineering demonstration.
3. Significance of integrated energy system
Proposing an integrated energy system has three meanings. First, innovate the management system. Realize the overall management and coordinated planning of multiple energy subsystems, and break down institutional barriers. Second, innovative technology. Through the research and development of the physical characteristics of heterogeneous energy sources, the complementarity and substitutability of various energy sources are clarified. Develop new technologies for conversion and storage, improve energy development and utilization efficiency, and break down technical barriers. Third, innovate the market model. Establish a unified market value measurement standard, and the conversion medium of value. Make energy conversion and complementarity reflect economic and social value, and constantly explore new potential markets.