Facing the attack of extreme natural disasters, how to avoid the apocalyptic blackout scenes from movies and TV shows becoming a reality, or at least ensure that the core areas of cities do not experience power outages, and minimize the potential socio-economic impact of disasters?
In response, China Southern Power Grid has for the first time proposed the concept of a disaster-prevention guaranteed power grid and released special plans for guaranteed power grids in 28 important cities. During the "13th Five-Year Plan" period, China Southern Power Grid will build guaranteed power grids in 28 important cities with an infrastructure investment of approximately 26.9 billion yuan, covering major cities in the southern region including Guangzhou and Shenzhen, as well as other prefecture-level cities whose central urban areas are in coastal strong wind zones or heavy ice zones.
"Since June, precipitation in southern China has significantly increased, and it is expected that 4-6 typhoons will make landfall on the coasts of Guangdong, Guangxi, and Hainan from July to September," said Xu Daming, Director of the Planning and Development Department of China Southern Power Grid. The company is located in areas prone to natural disasters such as typhoons, low-temperature rain, snow, freezing, earthquakes, and mudslides, making it susceptible to natural disaster disruptions.
According to the plan, during the "13th Five-Year Plan" period, China Southern Power Grid will focus on promoting the planning and construction of guaranteed power grids in 28 important cities, including 15 major cities such as Guangzhou, Shenzhen, Nanning, Kunming, Guiyang, and Haikou, as well as 13 other prefecture-level cities like Zhanjiang and Qujing, whose central urban areas are in coastal strong wind zones or heavy ice zones.
In these 28 cities, China Southern Power Grid will appropriately raise the design standards for guaranteed power grids. New guaranteed power grid projects planned in coastal strong wind zones will be constructed according to a 50-year return period for meteorological events, which is expected to improve the wind resistance of overhead lines at 220 kV and below by 20%-25%. In coastal areas, the company will combine urban planning and development needs, such as integrated utility tunnel construction, to promote the cable conversion of guaranteed lines and the indoor conversion of guaranteed substations. In medium to heavy ice zones, guaranteed lines will be equipped with ice-melting devices to ensure that the guaranteed power grid's "grid framework does not collapse" during ice disasters.
Xu Daming believes that the construction of guaranteed power grids is about shifting disaster prevention and resistance in the power grid towards "active defense." "Conventional power grid construction mainly aims to provide electricity to everyone, with all regions built to the same standard, without much consideration for disaster prevention in core areas. Once a natural disaster like a typhoon causes a power outage, we can only passively carry out repairs," he said. Now, building guaranteed power grids means comprehensively analyzing past disaster occurrences and proactively raising the disaster prevention level in core areas. Xu Daming revealed that the power grids in the 28 cities within this planning scope will adopt corresponding measures based on their respective disaster characteristics.
According to the guaranteed power grid construction plan, it is expected that by 2020, the disaster-prevention guaranteed power grids in the 28 important cities will cover an average of about 80% of key users, with 220 kV guaranteed power grids accounting for about one-third of the total scale on average, and 110 kV guaranteed power grids accounting for about 20% of the total scale on average.
