China Southern Power Grid (CSPG) is one of the two major state-owned electric utility companies in China, the other being the State Grid Corporation of China. Established in 2002, CSPG is responsible for distributing electricity to the five southern provinces of Guangdong, Guangxi, Yunnan, Guizhou, and Hainan, covering an area of more than 1 million square kilometres with a population of more than 250 million people.
CSPG operates a extensive network comprised of transmission lines and substations, with the length of its ultra-high voltage (UHV) transmission lines exceeding 10,000 kilometers and UHV receiving a major focus in expansion plans. By 2021, the company boasted over 45,000 km of 500 kV lines. (The towers near the cache location are 220kV.)
CSPG is primarily a transmission and distribution company and doesn't own generating assets like power plants.
For comparison, the other state-owned power grid company in China, State Grid Corporation of China (SGCC), is even larger, serving a vast area of East and Central China, as well as several other countries through its international investments. As of 2020, SGCC was the largest utility company in the world by revenue.
The cache requires a bit of climbing but only a few rungs up.