A green transformer refers to a type of transformer that meets the requirements of high efficiency, energy-saving, scientific material usage, low carbon emissions, environmental protection, reliability, and high recyclability throughout its entire lifecycle, including raw material procurement, manufacturing, packaging, transportation, operation, maintenance, and recycling. These products conform to the energy efficiency standards of high-efficiency energy-saving transformers (GB20052) and aim to minimize negative environmental impacts. They align with the national strategies of low carbon and circular economy.
Green transformers incorporate "eco-design" principles, ensuring that green characteristics are considered at every stage, including raw material procurement, product design and manufacturing, testing, packaging, transportation, installation, use, and recycling. The key technical features of green transformers are highlighted in four main areas: high efficiency, resource and material conservation, low carbon emissions, and safety and reliability.
At present, the main types of green transformers in China include the following: three-dimensional wound core transformers, open-type dry transformers, amorphous alloy three-dimensional wound core open-type transformers, amorphous dry-type transformers, natural ester (plant insulation oil) oil-immersed transformers, and silicone rubber-insulated dry-type transformers. These green transformers are widely used across various industries, offering users excellent low-carbon and environmentally friendly options due to their high efficiency, resource savings, low-carbon impact, and reliability.
The widespread application of these transformers not only demonstrates China's progress in green technology but also contributes significantly to promoting sustainable development and environmental protection. As such, green transformers are a key focus for advocacy and development in the future.
Application of Green Transformers in Energy Storage Stations
Energy storage stations have specific requirements for the transformers they integrate. Firstly, since energy storage stations operate under both charging and discharging conditions, transformers must meet strict safety requirements, particularly in preventing overexcitation. Secondly, energy savings are a key consideration given the high costs and valuable stored energy of energy storage stations. Moreover, as energy storage stations are usually located near load centers, there are stringent fire safety requirements for transformer design and materials.
Green transformers have been developed to meet these requirements. During the design process, the magnetic flux density should not exceed 1.5 Tesla to prevent overexcitation and increased no-load loss during discharge conditions. Whether charging or discharging, the transformer must operate near full load, so load loss must be minimized to conserve precious stored energy. As such, ultra-efficient transformers, surpassing the highest energy efficiency standards, are the ideal choice.
Since storage transformers are typically installed in outdoor containers with high ambient temperatures, transformers must meet high thermal endurance standards. Additionally, cooling fans are usually installed on container walls for heat dissipation, imposing stricter requirements on the dustproof and moisture-proof performance of the transformer. Encapsulated or sealed transformers are recommended to meet these demands.
Application of Green Transformers in Photovoltaic Power Generation Projects
Photovoltaic (PV) power stations require power transformers to connect to the grid. For PV stations with capacities above 10 MW, liquid-immersed transformers are generally preferred. Compared to traditional mineral oil transformers, plant oil transformers offer several advantages. Under the same conditions, natural ester (plant oil) transformers have higher thermal endurance and can tolerate higher temperature rises under overload conditions, allowing for smaller transformer sizes in PV stations and reducing costs. Additionally, natural ester (plant oil) is highly environmentally friendly, with a degradation rate close to 100%, posing no environmental burden, and is non-toxic, posing no harm to humans, animals, or plants. Its carbon emissions throughout the lifecycle are only 1/64 of that of traditional mineral oil. More importantly, plant oil (natural ester) transformers also have excellent fire resistance.