With the continuous and rapid development of human technology, the required energy consumption has also gradually increased. Due to the current dependence of human energy mainly including oil, natural gas, coal, and nuclear energy, these consumable energy sources have gradually decreased with use, raw material prices have also skyrocketed, and energy and economic crises have emerged. The figure reflects the current situation of China’s petrochemical energy reserves, and energy shortages in China may occur at any time. In addition, utilizing these consumable energy sources for power generation can also have direct or indirect impacts on the Earth’s environment, and even pose certain risks to humanity. For example, thermal power generation emits a large amount of carbon dioxide into the atmosphere, causing an increase in global average temperatures and water levels. Nuclear power generation is also subject to various natural and man-made disasters, such as the Chernobyl and Fukushima nuclear disasters, due to human negligence. In recent years, due to severe global climate change and rising anti nuclear awareness, advanced countries have actively sought various renewable energy sources such as solar energy, wind energy, tidal energy, geothermal energy, etc. to replace consumable energy. Therefore, research on renewable energy has been increasing rapidly. China has a vast territory, a large population, and a high demand for energy. It has enormous potential in the development of solar energy and is suitable for researching related technologies of solar energy, especially in the field of household use.
Human beings began researching solar power generation technology in the 19th century, based on the principle of photoelectric conversion, directly converting solar radiation energy into electrical energy. Solar power generation systems can be divided into off grid self use solar power generation systems (including various “photovoltaic+energy storage” power generation systems composed of off grid power supply solar inverters and energy storage batteries) and solar power generation systems that feed into the grid by connecting to the public grid (requiring connection to the public grid and sending electricity to the grid through solar grid connected inverters).
The transition from traditional energy sources to new energy sources is crucial for achieving carbon neutrality goals, and “photovoltaic+energy storage” can play an important role. In the field of household solar power generation and energy storage, the application subjects include various types of end-users of household electricity. With the development of photovoltaic module manufacturing technology, the cost of solar power generation equipment is gradually decreasing, and the application scope is also gradually expanding. The “photovoltaic+energy storage” system can balance the electricity fees waived by installers with the system investment cost. At the same time, for installation, in some areas, “photovoltaic+energy storage” can also be chosen to solve the problem of insufficient grid coverage. Many residential areas in developed countries in Europe and America are independent residences, which are very suitable for building independent photovoltaic power generation and energy storage systems. According to census data from various regional statistical agencies, the proportion of independent/semi independent housing in developed regions such as Europe, the United States, Japan, and Australia exceeds 50%. The trend of large-scale development in the household energy storage market has shown that the industry as a whole is expected to continue to grow at a high level. In China, in order to fully leverage the role of electricity price leverage in guiding the optimization and allocation of power resources, promote green and low-carbon energy consumption, and improve the operational efficiency of the power system, the government has begun to implement peak valley time of use electricity pricing system for commercial and industrial users. The proposal of national policies has gradually highlighted the practical value of the “photovoltaic+energy storage” system in national economic life. The “photovoltaic+energy storage” system has the ability to spontaneously self use and stagger peak electricity consumption through energy storage batteries, which can make the actual electricity consumption more uniform in time distribution, reduce the grid electricity consumption, transformer capacity, and maximum required electricity consumption during peak periods, and simultaneously reduce electricity prices and basic electricity prices, To reduce carbon emissions and improve the efficiency of power grid operation. At present, China has implemented many plans and projects to develop and utilize solar energy. During the 13th Five Year Plan period of the country, a policy was formulated to simultaneously build centralized large-scale solar power plants and small distributed solar power plants. The installation of solar power generation in cities and residential areas is also relatively convenient and suitable for large-scale promotion and application.
The household solar off grid inverter energy storage system studied is designed for distributed development and utilization of solar energy, and has broad application value.
Solar power generation systems have the following advantages compared to traditional power generation systems:
(1) Solar energy resources are very abundant, and solar radiation energy is endless. Therefore, the available power generation resources for solar power generation are the most abundant.
(2) Solar power generation is safer and more reliable, without incidental pollution and noise generation, and can operate safely and stably. The system can be flexibly configured according to actual applications.
(3) The application of solar power generation can more effectively solve the electricity consumption problem in areas without grid coverage, because solar energy resources are a type of energy that can be released in every corner of the world and obtained in every region.
(4) Solar power generation systems can be well integrated with buildings, saving land resources.