参考答案： The government has invested more than 550 billion yuan in power grid upgrading projects for rural areas, fundamentally improving access to electricity for rural residents. The Qinghai-Tibet electricity network project has been completed, connecting the power grid of the Tibetan plateau with those of the other parts of China. The state is accelerating the construction of electric power facilities in areas that as yet do not have electricity, and has so far ensured that more than 30 million people have access to electricity. Combined heat and power projects with a total installed capacity of 70 million kw have been built in high-altitude and frigid areas in northern China that provide more than 40 million urban residents access to heating.
As the world's largest energy producer, China mainly relies on its own strength to develop energy, and its rate of self-sufficiency has reached around 90 percent. China's energy development not only guarantees domestic economic and social development, but also makes significant contributions to global energy security. For some time to come, China's industrialization and urbanization will continue to accelerate, and the demand for energy will go on increasing, and so its energy supply will confront increasingly tougher challenges.