Five aspects of smart grid: both intelligent and energy-saving

　 In our economic life, power grids play an increasingly important role in economic and social development, energy structure adjustment, and climate change response. The intelligent development of power grids is an inevitable trend. Smart grids help energy conservation and emission reduction, and play an important role in power generation, transmission, distribution, transformation, power consumption, power dispatching and communication. We interpret the energy conservation and emission reduction effects of smart grids from the five links of smart grid generation, transmission, distribution, transformation and consumption.

　　Power Generation

　 　Environmental value of the national wind, solar, storage and transmission demonstration project

　　 Integrates wind power generation, photovoltaic power generation, energy storage system and intelligent power transmission

　　 The project will reduce carbon dioxide emissions by 270,000 tons per year

　　 The cumulative power generation has reached nearly 150 million kWh

　　By midsummer, the sky was clear and the clouds were light on the plateau outside the Great Wall. The project's largest number of grid-connected wind farms, the world's largest installed power-regulated photovoltaic power station, and the world's largest multi-type chemical energy storage power station were operating efficiently and reliably, in a stable and good state, presenting a busy and orderly scene everywhere. So far, the National Wind, Solar, Storage and Transmission Project has generated nearly 150 million kWh of electricity.

　　The National Wind, Solar, Storage and Transmission Demonstration Project, located in Dahe Township, Zhangbei County, Hebei Province, is located in a national-level 10 million kilowatt wind power base rich in wind and solar resources. It is currently the world's largest new energy demonstration power station integrating wind power generation, photovoltaic power generation, energy storage system and intelligent power transmission. The project uses the world's first wind, solar, storage and transmission combined power generation model, actively adopts new products and equipment in the field of new energy power generation, and follows the construction requirements of 100,000 kilowatts of wind power, 40,000 kilowatts of photovoltaic power generation, 20,000 kilowatts of energy storage, and a 220 kV smart substation. Since its completion and commissioning on December 25, 2011, it has fully exerted its unique advantages of being large, wide, complete and new. Under the framework of smart grid technology, through targeted and key research, it has initially realized the transformation of wind and solar power sources that are difficult to predict, control and dispatch into high-quality green power sources, becoming a new highlight in my country's efforts to promote energy conservation and emission reduction and accelerate the sustainable development of the new energy industry.

　　According to the internationally accepted conversion model, the project will actually reduce carbon dioxide emissions by 270,000 tons per year, which is equivalent to the carbon dioxide produced by burning 7.6079 million liters of gasoline, 416,000 barrels of crude oil, 9.36 tons of standard coal, and 10,100 cubic meters of natural gas. It is also equivalent to the carbon dioxide that can be absorbed annually by planting 4.602 million 10-year-old trees.

　　The digital indicator of annual carbon dioxide emission reduction of 270,000 tons is not just a simple appearance, but also represents the country's scientific measures to implement environmental protection, energy conservation and emission reduction, and vigorously promote the development of green energy. The National Wind, Solar, Storage and Transmission Demonstration Project has shown newer and stronger actions in promoting energy conservation and emission reduction and promoting the green transformation of energy development methods, and has provided a scientific and reliable "wind and solar answer" for opening a new era of human energy utilization.

　　Power Transmission

　　Ultra-high voltage: making smart grids more energy-efficient and more robust

　　 The world's first 1000 kV UHV AC test demonstration project

　　 Greater power transmission efficiency and less power transmission loss

　　 Effectively reduce the intermediate links in coal transportation and improve energy transmission efficiency

　　On January 6, 2009, the world's first Southeast Shanxi-Nanyang-Jingmen 1000 kV UHV AC test demonstration project was officially put into operation, and the 1000 kV Changzhi substation was settled in Shanxi. Since then, UHV has provided a high-speed channel for the energy and economic transformation of Shanxi Province, playing an important role in "optimizing resource allocation and promoting energy conservation and emission reduction".

　　In order to ensure the safe and stable operation of UHV substations, Shanxi Provincial Maintenance Company vigorously promotes lean management, carries out standardized equipment inspections, statistical analysis of operating data, and regular switching maintenance, and continues to carry out technical supervision and analysis of UHV equipment. It has established a "four-in-one" UHV emergency protection system formed by operation and maintenance units, equipment manufacturers, technical supervision units, and engineering installation, construction and maintenance units, as well as a long-term and efficient cooperative linkage emergency repair mechanism, which provides strong guarantees for ensuring the safe and stable operation of UHV power grids.

　On December 16, 2011, the UHV expansion project was officially put into operation. The People's Daily published a report titled "China's Electricity 'Highway' Successfully Expands UHV Capacity to Achieve 'China's Leading'". The article pointed out that the commissioning of this high-speed channel of UHV means greater power transmission efficiency and less power transmission loss, which means that a large amount of transportation capacity can be saved and higher land utilization. In addition, UHV power transmission can effectively reduce the intermediate links of coal transportation and improve energy transmission efficiency.

　　Here is a set of data: As of January 10, 2012, the 1,000 kV UHV AC test demonstration project, which has been in continuous and safe operation, has transmitted 18.254 billion kWh of electricity from Shanxi Province, which is equivalent to replacing 5.9 million tons of coal, reducing the shipment of 20,000-ton heavy-load trains by 295 times, and reducing carbon dioxide emissions by 16.03 million tons, bringing direct economic benefits of about 30 billion yuan to the central China region.

　　The goal of my country's power grid development is to build a strong smart grid that is safe, reliable, economical, efficient, clean, environmentally friendly, transparent, open, and friendly and interactive. The ultra-high voltage power grid will make the smart grid more energy-efficient and stronger.

　　Substation

　　Smart substation: small body with big power

　　 Compact layout, simple structure, and new intelligent devices

　　 The site area was reduced by 6.2 acres, saving about 23% of land resources

　　 Realize unattended operation and automated operation process

　　Smart substation is one of the core platforms for realizing energy conversion and control in a strong smart grid. As an important support for realizing the access of various new energy sources to the grid, its own energy conservation is also greatly admired. On June 11, the reporter visited the Yanling Substation, the first 220 kV smart substation in Henan Province.

　　Walking into the gate of the substation, the first feeling is that compared with the traditional 220 kV substation, the layout of this station is more compact and the structure is simpler. "The reason why Yanling Substation is 'small' is that it uses an electronic transformer based on the principle of magneto-optical glass. This transformer has simple insulation, small size and light weight. It can be installed in combination with the electronic transformer and the disconnector, which reduces the longitudinal layout size of the 220 kV distribution area by 3 to 4 meters and the longitudinal layout size of the 110 kV distribution area by 2 to 3 meters. Combined with the optimization of the whole station structure and the optimization of the overall layout, compared with the general design of the 220 kV substation, the whole station has reduced the area by 6.2 acres, saving about 23% of land resources." Wang Yi, the electrical project manager of the station, introduced to reporters.

　　Walking into the secondary equipment room, it feels like the room has shrunk, and the number of various secondary cabinets arranged inside has been greatly reduced. According to Wang Yi, traditional 220 kV substations generally have more than 100 measurement and control cabinets, protection cabinets, and metering cabinets. Yanling Substation has a total of 66 secondary cabinets by adopting new intelligent devices, optimizing layout, and merging rooms, which is nearly 40% less than conventional projects. The building area of ​​the entire station has been reduced by more than 350 square meters compared with the general design.

　　Looking around the Yanling substation, the reporter found that it did not have a spacious and bright main control room like traditional substations, but only a small guard room next to the station gate. So, how is the equipment operation of the station carried out? It turns out that the Yanling substation is an unmanned substation of the Huadu 500 kV substation and is controlled by the Huadu substation control center. The operation team is located in the Meixiang 110 kV substation, 3 kilometers away from the station.

　　According to the operators, Yanling Substation adopts one-button sequential control. This operation is completely different from conventional substations, and is very convenient and fast. For example, the switching on and off of the main transformer takes about half an hour under the traditional operation mode, but with one-button operation, the operation is completed with one command, which takes a total of 3 minutes and 57 seconds. From more than half an hour to more than 3 minutes, the efficiency has increased by 10 times.

　　power distribution

　　Urban power distribution automation: making electricity more reliable

　　 The average fault isolation time was shortened from 35 minutes to 30 seconds, and the power supply reliability rate was increased to 99.99%.

　　 Isolate the fault in the shortest possible time to avoid power outages in non-fault areas

　　 Rapidly locate the fault area and effectively shorten the fault handling time

At the Qingdao Olympic Sailing Base in Shandong, four ring main units with bright sea blue as the base color and exquisite patterns are neatly placed on the roadside, blending in seamlessly with the surrounding environment. These are the first "intelligent surface protection" ring main units in China. "Intelligent surface protection" uses peer-to-peer communication between terminals to make accurate logical judgments on the fault area based on the fault current, isolate the fault in the shortest time, avoid power outages in non-fault areas, and minimize the fault power outage area.

　　On January 1, 2011, the distribution automation system of Qingdao Power Supply Company was put into operation. The on-site transformation and system access of the primary and secondary equipment of 32 lines in the 5.3 square kilometer pilot area were completed, realizing the feeder automation function, shortening the average fault isolation time from 35 minutes to 30 seconds, and increasing the power supply reliability from 99.964% to 99.99%, greatly improving the power supply reliability of customers.

　　The number, duration and scope of power outages in the distribution automation system use area have been greatly reduced, the quality of power has been significantly improved, and power users are more assured. "Our products are electronic products, which rely heavily on power supply reliability. Due to production needs, 80% of the production equipment in the factory cannot be shut down. If there are many power outages, it will have a great impact on the quality of electronic products." The person in charge of Qingdao Aojia Electronic Products Co., Ltd. told us. Previously, in order to ensure that the company's power supply is 100% reliable, Aojia purchased two high-power diesel generators to prevent emergencies. This not only increased the company's operating costs, but the use of diesel generators also consumed a large amount of oil resources and increased atmospheric carbon dioxide emissions.

　　After the Qingdao Power Supply Company's distribution automation system was put into operation, the workload of daily operation and maintenance of the distribution network system was reduced, especially the time for accident investigation and repair and maintenance. It is estimated that the maintenance cost can be reduced by more than 3 million yuan each year. At the same time, by integrating the data of distribution network operation, maintenance, and online monitoring, the fault area can be quickly located, effectively shortening the fault handling time.

　　Electricity

　　New experience of smart electricity life

　　 Self-service electricity bill inquiry and payment convenience

　　 Smart home realizes intelligent control of home appliances

　　 The community has everything from photovoltaic power generation to electric vehicle charging

　　"The cool and pleasant indoor temperature, the fragrant rice in the rice cooker, the preheated bath water in the electric water heater... Before leaving get off work, I preset these on my office computer and enjoy them when I get home." On June 8, the author came to Jiaxin Qinyuan in Yubei District, Chongqing. In the newly renovated room, resident Liu Yongxiang happily described his smart life to the author.

　　At the smart community property management office, through the self-service payment terminal, the entire process from clicking on the self-service payment, selecting the payment amount, executing the payment, to checking the payment result can be completed in less than a minute. The property management center can also meet the catering, medical, housekeeping and other services reported by community residents.

　　When he arrived at his home, Liu Yongxiang excitedly introduced his smart home, "Look at this, touch here to start the automatic curtains, air purifiers and other home appliances. Oh, let me show you this." Liu Yongxiang skillfully operated the smart interactive terminal. When he touched "Start background sound", the beautiful melody of "Spring" sounded in the room. "Such a smart community, the decoration cost is only a hundred yuan more per square meter than ordinary decoration, but it can bring such a convenient life. Friends and relatives who have come to my home are very envious!" Liu Yongxiang said.

　　Afterwards, on the TV that integrates three networks, Liu Yongxiang checked this month's electricity consumption information and today's electricity consumption index.

　　In his opinion, smart life will become more popular in the future, and smart electricity communities will also provide residents with a low-carbon lifestyle that increases revenue and reduces expenditure.

　　There is a set of black solar panels on the roof of Liu Yongxiang's house, which is a photovoltaic power generation system. The system uses solar energy to generate electricity, and each household can generate 8 kWh of electricity per day on average, and up to 12 kWh at a maximum. "This highly clean and recyclable energy makes low carbon possible. The smart devices in our home also provide the option of a 'throttling' mode."

　　Liu Yongxiang then showed the smart interactive terminal installed in the lobby. This 9-inch screen controls all smart home appliances in the house and can collect electricity usage information of all appliances through smart sockets. The smart interactive terminal also provides residents with four electricity usage modes: going out, sleeping, comfortable, and economical, and can display the low-carbon index.

　　"Since we moved into the smart community, we have become trendsetters in the unit. Many colleagues often come to visit to see what's new. Charging piles are also installed in the parking garage in the community. When the time comes, we will buy an electric car." Liu Yongxiang's wife Hui Fuhui said with a smile.

　　It is understood that Jiaxin Qinyuan is the first smart electricity community in China with a scale of over 1,000 households and officially put into operation. It was completed on June 28, 2010. Chongqing Electric Power Company will use the experience accumulated from the pilot to gradually expand the coverage of smart communities to all core areas of Liangjiang New District.