Install a 'windmill' on the roof of the world

The blue sky and white clouds cover the green mountains, and the snowy plateau boasts beautiful scenery. Xizang not only has beautiful scenery, but also contains rich energy treasures. Wind power resources are one of them.

Recently, the world's highest altitude wind power project under construction - Datang Xizang Energy Development Co., Ltd. Basu 100 MW guaranteed grid connected wind power project (hereinafter referred to as "Basu Wind Power Project") successfully completed the hoisting of the first wind turbine on the southeast Tibetan plateau with an altitude of more than 5200 meters. The project is located in Bangda Town and Kawabaiqing Township, Basu County, Changdu City, Xizang Autonomous Region, and is expected to be fully completed and put into operation by the end of October this year. After being put into operation, it can add over 223 million kilowatt hours of clean electricity annually.

Compared with coal-fired power plants, according to the calculation of standard coal consumption for power supply, the project can save about 73100 tons of standard coal per year, reduce carbon dioxide emissions by about 182800 tons, sulfur dioxide emissions by about 621.39 tons, smoke emissions by about 3333.56 tons, and nitrogen oxide emissions by about 540.97 tons.

"The project has remarkable energy, ecological and social benefits, which can not only effectively supplement Xizang's energy supply, but also effectively alleviate the environmental protection pressure of the local power industry, and play a positive role in driving the rapid development of regional economy." An Gang, the party secretary and executive director of Datang Xizang Datang International Nujiang Upstream Hydropower Development Co., Ltd., an enterprise affiliated to Datang Xizang Energy Development Co., Ltd., told reporters.

Wind solar complementary continuous power generation

In 2022, the Guiding Opinions on Promoting the High Quality Development of Energy in Xizang issued by the National Energy Administration put forward that efforts should be made to accelerate the construction of the national clean energy base and improve energy security capability; Efforts will be made to strengthen local support for power supply construction and enhance the capacity of clean energy supply; Efforts will be made to strengthen the construction of energy infrastructure and improve the level of universal electricity services; We will strive to promote the transformation and upgrading of energy consumption, build a national demonstration zone for renewable energy utilization, accelerate the construction of a clean, low-carbon, safe and efficient energy system, and provide a strong and reliable energy guarantee for promoting high-quality economic development and long-term social stability in Xizang.

At present, Xizang's energy structure is dominated by hydropower and photovoltaic, with hydropower generating capacity accounting for 89.81% of the total generating capacity and solar power generating capacity accounting for 7.73%. The development and utilization of both are relatively mature. However, both hydroelectric and photovoltaic power generation have a certain periodicity - hydroelectric power generation has a surplus in summer and a shortage in winter, while photovoltaic power generation has a surplus during the day and a shortage at night.

How to solve this problem? Developing wind power generation is a feasible approach.

Xizang is located on the Qinghai Tibet Plateau, the roof of the world. Due to its special terrain and large temperature difference between day and night, it is rich in wind energy resources. According to preliminary estimates, the area with wind energy resources of more than 7 meters per second in Xizang accounts for about 30% of the total area of the region, which is mainly distributed in high mountain areas with an altitude of more than 4800 meters, and the technically exploitable capacity is about 180 million kilowatts.

"Technological innovation and engineering practice in recent years have strongly proved that Xizang's wind energy not only has considerable development value, but also can produce significant economic and social benefits." Wang Honglang, the person in charge of Datang Basu Wind Power Project, said that after in-depth analysis and judgment of the resources in Changdu, the company found that local wind energy is small in the day and large at night, which is the opposite of photovoltaic power generation. Developing the Basu wind power project and connecting its generated energy to the Changdu power grid can form a complementary wind solar system, continuously producing sufficient and clean electricity resources during the low season of photovoltaic and hydropower generation, and achieving the maximum utilization of renewable energy, "said Wang Honglang.

Prevent wind turbine altitude sickness

In new energy projects, areas with an altitude of 3500 to 5500 meters are generally referred to as ultra-high altitude areas. The Basu Wind Power Project is a bona fide new energy project in high-altitude areas, with an average elevation of 5050 meters at the site and a maximum elevation of 5305 meters for the wind turbine nacelle.

Human beings entering high-altitude areas may experience altitude sickness, and if wind turbines in low altitude areas are installed directly in high-altitude areas without improvement, there may also be "altitude sickness": the air in high-altitude areas is thin, and the stability of wind turbines is poor; Poor heat dissipation conditions can easily cause overheating of fan bearings, reducing the service life of the unit. This will greatly affect the efficiency of wind power projects and even pose certain safety hazards. We carefully select wind turbine types based on the characteristics of high-altitude areas and carry out a series of special designs, "said Wang Honglang.

In terms of unit type selection, the Eight Mansions Wind Power Project has chosen high-efficiency breeze wind turbines. The low air density in the project area results in a lower wind power density, and traditional wind turbines may not have enough to eat. Therefore, we chose high-efficiency breeze wind turbines in the project to better adapt to the special environment of low wind speed and low wind power density. According to calculations, compared to traditional wind turbines, high-efficiency breeze wind turbines can increase wind energy conversion efficiency by about 20%, "said Wang Honglang.

In terms of unit optimization design, the Basu wind power project improves unit efficiency by increasing blade length and adjusting main control parameters; Optimize the heat dissipation performance of key components such as generators, inverters, and cooling fans; Improve the insulation and withstand voltage levels of various electrical components, increase the gap between copper bars or busbars of motors and frequency converters, and enhance insulation and withstand voltage performance; Apply anti radiation coating on the surface of wind turbine blades to better cope with sunlight radiation in high-altitude areas.

The Basu Wind Power Project requires the installation of a total of 20 wind turbines, with a hub center height of 110 meters and an impeller diameter of 195 meters. The maximum sweeping area of the blades exceeds 30000 square meters, equivalent to the area of more than four standard football fields. At full wind speed, a single unit can generate 9.5 kilowatt hours of electricity per revolution.

In Angang's view, the Basu wind power project is just the beginning. Active policy guidance, continuous technological breakthroughs and gradual improvement of Xizang's energy infrastructure will help Xizang develop wind power.

Accelerate the landing of high-altitude wind power projects

Recently, the Jicuo 100 MW wind power storage integration project was officially started in Seni District, Naqu City, Xizang, with an average altitude of 5000 meters. The project plans to construct 18 wind turbines with a single capacity of 5.6 megawatts, with a total installed capacity of 100 megawatts; The synchronized energy storage system can output 80000 kilowatt hours of electricity continuously for 4 hours.

Previously, the Omatingga 100 MW wind power project had been completed and put into operation in Sini District, Nagqu City, with an average elevation of 4650 meters at the site. The project consists of 25 wind turbines with a single capacity of 4 megawatts, with a total installed capacity of 100 megawatts. The project can provide about 200 million kilowatt hours of clean electricity annually, meeting the annual electricity consumption of 230000 local people, saving about 60000 tons of standard coal, and reducing carbon dioxide emissions by about 160000 tons.

In August 2023, the first five 3.6MW wind turbines of the Chomeizhegu Wind Farm in Xizang, located at an altitude of more than 5000 meters, were successfully connected to the grid for power generation. This is the first ultra-high altitude wind power development technology research and technology demonstration project in Xizang, and also the first wind power project integrated into Xizang's main power grid.