“ Frontline research ”
Original title: Ecological efficiency, villagers' income, a win-win road for a photovoltaic power station (theme)
——Visiting Sayongshan 250MW PV Power Station in Luquan County, Kunming, Yunnan Province (subtitle)
People's Daily reporter Lv Zhongzheng Li Maoying
General Secretary Xi Jinping stressed that "accelerating the innovation of green science and technology and the promotion and application of advanced green technology, strengthening the green manufacturing industry, developing the green service industry, and strengthening the green energy industry".
As an important part of green energy, photovoltaic is booming, and the new installed capacity of photovoltaic in China has ranked first in the world for many consecutive years. Today, China has not only a complete photovoltaic industry chain and technology, but also the world's largest photovoltaic power generation scale.
What is the specific situation of PV downstream application link? How to give play to greater benefits and help green development? The reporter recently walked into the mountainous area of northern Yunnan to decode the planning, construction and future prospects of surging green electricity.
——Editor
Yunnan Guizhou Plateau, deep valleys and mountains, under the sun, the photovoltaic panels are shining like fish scales.
With a dip angle of 24 degrees and up to 540000 pieces, in the northeast of Sayingpan Town, Luquan Yi and Miao Autonomous County, more than 130 kilometers north of Kunming, Yunnan, the Sayongshan 250 MW centralized photovoltaic power station converts solar energy into clean energy, and transmits it to factories, hospitals, and residential areas
Sayongshan photovoltaic power station is the photovoltaic power generation project with the highest single put into production power generation capacity in Yunnan Province, and also the first recorded project among the local "8+3" new energy projects. In 2023, the new grid connected capacity of centralized photovoltaic power generation in Yunnan will reach 14.407 million kilowatts, ranking first in China.
More than 100 years ago, the "photovoltaic effect" was accidentally discovered in an experiment. Today, photovoltaic power stations have spread across five continents. Among them, the centralized photovoltaic power station occupies the mainstream position of photovoltaic installation because it can be connected to the high-voltage transmission system to supply long-distance loads. In Sayongshan, Luquan, Yunnan, 250 MW centralized photovoltaic power stations have been connected to the grid for more than a year, and the cumulative power generation has exceeded 340 million kilowatt hours. How to plan and build this power station, and how to give full play to its comprehensive benefits? What is the prospect of photovoltaic application? The reporter conducted a field survey.
plan
Accurate site selection and multi factor guarantee
It is not easy to explore the path of photovoltaic power station among mountains. After several hours of traveling, I finally arrived at the top of Sayong Mountain. It was suddenly clear——
Under the blue sky and white clouds, there are not only large photovoltaic arrays, but also scattered photovoltaic panels winding and scattered.
Why choose to build large photovoltaic power stations in mountains? Why is the PV array irregularly distributed? A series of questions to be answered.
"Despite the mountains, due to the high altitude, less shelter and better lighting conditions, the annual average full load utilization hours of the power station are more than 1300 hours." Wang Weichuan, deputy director of Luquan County Development and Reform Bureau, introduced.
"This project is composed of five plots, covering a total area of about 5235 mu." The investor Huadian (Yunnan) New Energy Power Generation Co., Ltd. Deputy General Manager introduced to Donghui that the country has strict policy requirements for photovoltaic land, and the early site selection should be as accurate as possible to the installation position of each photovoltaic panel, which makes the design difficult.
"Through multiple procedures such as spot query and field survey, we finally determined the 5000 mu of land from a large range of delimitation." Xiang Donghui said that the site selection is the first step to build a photovoltaic power station, which not only needs to comprehensively consider the orientation of photovoltaic panels, topography and geology, and good grid access, but also avoid "three zones and three lines", farmland, arbor forests, natural shrubbery The irregular distribution of photovoltaic array is caused by such factors as nut oil tea gardens, minerals, etc.
What will happen if the site selection is not accurate enough?
"It will increase the quantities of roads and power collection lines, thus increasing the project investment, which will make it difficult for some projects to meet the industry income requirements." Zhang Jian, the professional chief engineer of the New Energy and Electric Power Engineering Institute of PowerChina Kunming Design&Research Institute, said that it is necessary to keep improving when selecting the project site, and try to choose a site with concentrated plots and good conditions.
In order to find the site that meets the requirements, the project team has carried out many site surveys in the mountains. "Once, when I climbed up the mountain with my team members for survey, we suddenly encountered heavy rain and shivered with cold. Fortunately, we found a cowshed and were able to light a fire for warmth." Long Peng, deputy general manager of Huadian Luquan New Energy Development Co., Ltd., said. The original appearance of the photovoltaic power station has been stamped out by a series of footprints in order to enlighten the mountains and forests.
Where does the money come from when the land is available? After all, a power station has a large investment and a long payback period.
At the initial stage of construction, project funding is a big problem. As a green energy project, photovoltaic is a key field of financial support for green and low-carbon development. This project has become the first batch of photovoltaic projects under the innovative mode of "carbon emission reduction linkage" of Industrial Bank Kunming Branch. A total of 920 million yuan of loans have been approved for the project, with a term of up to 15 years.
build
Innovate technology and improve unit output
Climbing high and looking into the distance, you can see that the mountains are always filled with photovoltaic panels. They fill the gap between mountains, forests and fields, extend across the ridge to the distance, and quietly absorb the energy of the sun.
The construction of mountain photovoltaic projects is difficult and costly due to the complex terrain conditions and irregular and scattered usable area. How to save land and improve power generation efficiency during construction?
The construction team introduced innovative engineering technology. "You see, this is the flexible photovoltaic support we designed, which can fix the photovoltaic panel without cement piles, only steel strands and lock structures." Yang Hongpeng, the manager of the EPC (general contracting mode) contractor, pointed to the photovoltaic module on the triangular truss in front of us, and said that the team continued to explore the optimal layout scheme for the mountainous areas with poor local terrain conditions and good lighting resources, The photovoltaic flexible support project with a span of 42 meters was implemented.
With the flexible photovoltaic support, the gap between modules is reduced, and the high-density layout of photovoltaic arrays is realized. "Compared with the fixed support, the flexible support reduces the land use index per megawatt by 1.45 mu, and the investment per kilowatt also decreases." Yang Hongpeng introduced that this technology has been popularized in the construction of many other mountain photovoltaic projects in Yunnan, greatly improving the land use efficiency.
The configuration of relevant equipment is the key to further improve the power generation efficiency within the limited land use. Booster station is the core equipment of photovoltaic power station, which boosts the electric energy generated by the power station to high voltage for transmission to the power grid. "Through optimization design, we have placed the 220 kV booster station in the middle of Lot 2, which is conducive to shortening the length of single circuit power collection line and reducing power loss," said Xiang Donghui.
Between Shengfa Village in Sayingpan Town and the mountains in Zhongping Town, the grid connection project of Sayongshan PV power station has also been completed. "The total length of this line is more than 24 kilometers, and there are 79 iron towers, which can connect the power generated by the substation to the 220kV medium screen substation." Chen Wei, the network connection project manager of Yunnan Kunming Power Supply Bureau of China Southern Power Grid, introduced that the application of new technologies such as UAV 3D laser scanning modeling ensured that the project was put into production on schedule.
synergism
Adjust measures to local conditions and bring into play comprehensive benefits
"Here is a collection of 540000 photovoltaic panels. This iron tower is the boundary between the photovoltaic power station and the China Southern Power Grid, and the generated energy can only be connected to the large power grid after passing through the iron tower." Walking into the booster station of the photovoltaic power station located on the mountainside, the head of the station Zhou Quansheng introduced that the green power generated by the power station can be fully connected to the grid. According to relevant policies, the construction cost can be recovered in about 15 years if the life of photovoltaic power station is 25 years.
In addition to its own input-output account, the comprehensive benefit account of the power station to the surrounding areas is also increasingly clear.
"We are going to plant 400 mu of Polygonatum and Bletilla striata respectively on plot 5, and the town government entrusts professional cooperatives to plant and operate them." Wang Haibin, deputy mayor of Sayingpan Town, said that cooperatives can give technical and sales guidance, and nearby villagers can participate in management and protection work such as planting and weeding to promote income growth.
These initiatives that benefit the people can be promoted thanks to the improvement of agricultural infrastructure under the condition of agricultural light complementation. "According to the development agreement, the company invested to improve the agricultural water conditions on the mountain and support the complementation between agriculture and light." In addition to land leveling in the early stage, Donghui introduced that it also built irrigation facilities such as dams, and hardened or repaired the surrounding roads, driving the annual net income of 300 land related farmers nearby to increase by more than 3000 yuan.
In Shengfa Village, Sayingpan Town, Wang Tianzhi, the village secretary, calculated an account for the reporter that Shengfa Village had more than 4600 mu of photovoltaic land leased to several photovoltaic projects of many enterprises, including Huadian, and the villagers could get about 500 yuan per mu of rent. In the agriculture light complementary project, nearby villagers participate in planting crops, which also has benefits.
"In 2020, the collective income of our village will be only 50000 yuan, and with the arrival of photovoltaic projects, it has now exceeded 2 million yuan." Wang Tianzhi said that many villagers participated in the construction of power stations to earn labor income; After the completion of the project, more than a dozen villagers have been employed at the gate of their homes and engaged in security, logistics and other work in the power station.
Wang Tianfu was once a poor family in the village. Previously, a family of four lived in a tile roofed house, but now he has moved into a three storey building. "I am now doing patrol work in the power station, and I will be paid 2400 yuan a month, with 20000 yuan of land circulation income every year. The better the day goes, the better."
Walking on the mountain path, Gesang flowers covered the roadside, and Pinus armandii seedlings grew tenaciously beside the gravel. In addition to social benefits, photovoltaic power stations also play a huge ecological benefit, reducing carbon dioxide emissions by more than 300000 tons annually; The project also implemented ecological restoration synchronously, and the surrounding ecological environment was significantly improved. "In addition to planting pasture, we also plant plants to promote the recovery of the natural environment in areas that do not have the conditions for agricultural planting. While restoring the ecology, the landscape has also been further improved." Long Pengxue introduced. Grass seeds are sown under photovoltaic panels, azaleas and pinus armandii are sown in rocky desertification areas... At the peak, more than 100 villagers around the power station are engaged in ecological restoration, and each person can earn 100 yuan a day for labor service.
For the local government, this power station has brought a win-win opportunity. "In terms of tax revenue, the project is expected to have a total value-added tax of about 260 million yuan and a total income tax of about 190 million yuan in 25 years, which will increase the annual industrial output of Luquan County by about 130 million yuan." Wang Weichuan said that the power station also has a leading effect in building a national demonstration base for the integration of scenery, water and storage in the lower reaches of Jinsha River in Luquan, effectively driving the adjustment of local industrial structure.
extension
Innovate technology, release surging green energy
When the reporter came to Huadian Yunnan New Energy Centralized Control Center, he saw the equipment status of the power station flashing on the large digital screen. Xiang Donghui introduced that according to the current installed scale of the company, more than 200 operators and 480 maintenance personnel are needed; After the intelligent control mode is fully adopted, only 40 operators and 183 maintenance personnel are needed, which can effectively reduce the operation and maintenance costs of the photovoltaic power station and improve the labor productivity of all employees.
In recent years, with the expansion of the construction scale of photovoltaic power stations, the demand for reducing the operation and maintenance costs has become more urgent. By applying more information technology to the energy field, remote centralized control and unattended are becoming a new mode of production management of centralized photovoltaic power stations.
Zeng Jianping, Deputy Secretary General of the National Strategic Advisory Committee for Building a Powerful Manufacturing Country, believes that photovoltaic industry is a typical field with high integration of new energy and information technology. At present, more and more new energy projects, including photovoltaic power stations, are implementing intelligent technology applications.
In January of this year, in order to implement the Action Plan for Innovative Development of Smart Photovoltaic Industry (2021-2025), the Ministry of Industry and Information Technology released the list of the fourth batch of smart photovoltaic pilot enterprises and projects, promoting the acceleration of intelligent manufacturing, intelligent applications, intelligent operation and maintenance, and intelligent scheduling, and comprehensively improving the quality and efficiency of photovoltaic industry development.
In addition to the gradual improvement of photovoltaic intelligent application level, the trend of cross-border integration of photovoltaic power generation in application scenarios in China has become more obvious in recent years.
Entering Luquan Industrial Park, the reporter saw rows of dark blue photovoltaic panels neatly installed on the roofs of several factories. "The power generation of the project can be used by enterprises such as food processing in the park. At present, the proportion of self use is up to 40%, and the surplus power can be connected to the Internet." Huang Cuodong, project manager of Luquan Suifa New Energy Co., Ltd., introduced that the average annual power generation of the distributed photovoltaic project can reach 2.12 million kilowatt hours.
In addition to the "PV+Industrial Park", the "PV+" comprehensive development mode in multiple scenarios will continue to promote the cross-border integration of PV.
In terms of distributed photovoltaic, all regions are actively expanding new space for industrial development. For example, Beijing proposed that the photovoltaic coverage rate of new public institution buildings and park roofs should not be less than 50%; According to the planning of Shanghai, from 2023 to 2025, the photovoltaic scale of new residential buildings in the city will exceed 100000 kW; In addition, Jiangsu and other places encourage the expansion and application of photovoltaic in transportation, communication, data center and other fields.
In terms of centralized photovoltaic, with the increasingly strict land management, it has become a trend to develop "photovoltaic+" mode hybrid photovoltaic power generation projects. Operators can simultaneously develop agriculture, forestry, animal husbandry, fishery and photovoltaic power generation businesses on the same plot, such as multi scenario hybrid photovoltaic projects such as agriculture photovoltaic complementation, forestry photovoltaic complementation, fishery photovoltaic complementation, animal husbandry photovoltaic complementation, etc., to improve comprehensive income.
At present, China is building a new power system with the proportion of new energy gradually increasing, and continues to promote the energy revolution, which also opens a wide space for downstream photovoltaic applications. For example, various regions are exploring photovoltaic hydrogen production, ammonia production, methanol production and other modes to expand the local consumption of green electricity.
Recently, the National Energy Administration issued a notice to actively support the development of new energy+energy storage, optical storage and charging integration and other joint transfer modes. "With the increasing abundance and proportion of photovoltaic downstream applications, the configuration of energy storage systems will greatly enhance the flexibility of photovoltaic power generation and reduce the peak shaving pressure of the power grid." Xiao Gang, a professor of the School of Energy Engineering of Zhejiang University, believes that in order to further expand the development space of photovoltaic applications, we should encourage the deployment of energy storage facilities on the power generation side, the power grid side, and the consumer side, Let new energy better serve the national development strategy and better serve the people's good life.
Standing at the foot of Sayong Mountain, looking up, the photovoltaic array is like a field sowing sunshine "seeds", constantly growing green power. Although this is a remote mountain area, the output of the barren mountain area also lights up the neon of the city, and continues to contribute to green and low-carbon development. In the past 30 years, the whole PV industry chain has taken advantage of the policy and industrial dividend to embrace the power of digitalization and become increasingly mature; In the future, with the further expansion of photovoltaic applications, photovoltaic modules will also appear in beaches, fish ponds, stations, mines... The photovoltaic industry will grow into a towering tree, lighting up a better life, and providing more opportunities and momentum for green and low-carbon development.
