Trends & future of power application of superconductivity technology in China

Author: admin / 2005-09-12

The average increasing rate of electrical power generation during past 10 year was about 7% per year in China. The total power generation capacity was 210 GW in year 1995 and reached 407 GW in year 2004. Although the country’s total capacity is now the 2nd in the world only after USA, due to the Chinese population, the capacity per capital is less than 1/3 of the developed country’s level. However, because of the fast rising consumption, the shortage in electricity is very severe in China now. The official figure of the power shortage was 30 GW in 2004, while many experts believe that the actual number could be much bigger if the method applied to calculate the shortage was different. The estimated total electricity consumption in 2020 would be about 4.5 trillion kwh and the capacity of power generation in 2020 would be about 950 GW. To generate such a large amount of electricity needs tremendous mineral resources. Mineral resources in China is about 12 percent of the total in the world. However, the resources per capita is only about half of the world's average. Generally speaking, China is in short supply of electricity now, and might be insufficient in mineral resources in the future. 


High Temperature Superconductivity (HTS) is a key technology targeting to solve above problems. Recently, supports for R&D of HTS from Chinese government are increasing. The national applied superconductivity program supported by Ministry of Science & Technology (MOST) is focused in three areas: 
1.Process technology of superconductors including the technologies of producing long BSCCO tape, MgB2 wires, low Tc wires, large area YBCO thin film, and coated conductor. 
2.Power application of superconductors including power cable, fault current limiter, transformer, magnets, motor, SMES, MRI, and MAGLEV.
3.Electronic application of superconductors including microwave filter, microwave receiver, SQUID, junctions and devices. 
The total amount of support from the Chinese MOST is 12M US$ with additional about 30 M US$ from provincial governments during the period from 2000-2005. 

Among the supported power application projects, HTS power cable and HTS fault current limiter are the most important projects. To provide HTS wires required by the power application projects, a project of producing Bi-2223 tape is also supported as an important project within this national program. A Chinese company, InnoST, has built a production line with a capacity of 200 kM Bi-2223 tape per year. The Bi-2223 tape produced by InnoST is supplied to several domestic power application projects, for example, the power cable, transformer, motor, SMES and magnets. Live grid trial operation of China’s first HTS superconducting power cable system (33.5m, 35kV, 2kA, 3 phase) was started at Puji Substation of China Southern Power Grid on April 19, 2004. This HTS cable replaced a part of the 35 kV bus line in the substation, distributing electricity to 4 industrial customers and a residential population of about 100,000. The cable project is leaded by a Chinese company named Innopower, a joint venture by Yunnan Power Group and InnoST. The fault current limiter project, leaded by Institute of Electrical Engineering, is also one of the important power application projects. The fault current limiter of 10.5 kV and 1.5 kA, based on using Bi-2223 tapes winding and power electronic circuit, will be connected to the power grid in Hunan province this year. Apart from the power application project, it is worth to mention the HTS microwave filter system for mobile communication. This project is mainly carried out by Tsinghua University involving a close collaboration with China Unicom, one of the two most important mobile communication companies in China. A HTS microwave filter system was installed successfully in a mobile phone base station in March 2004. A mobile communication cluster formed by 5 base stations equipped with HTS microwave filer system will be also installed in Beijing this year. 

Above content of applied superconductivity program is for the period from year 2000 to 2005. Now, it is the time for making a plan for next 5 years. Based on the economic situation in China, the HTS power application would still be very important in the new program. To produce HTS power devices needs a lot of HTS wires. Although the coated conductor attracts many attentions, my personal point of view is that, due to the process cost, the time for coated conductor to take over BSCCO tapes could be much longer than what most people have been told. The R&D of HTS power application could not wait until the coated conductor is ready. The projects of HTS power application will mainly count on BSCCO wires/tapes within a rather long period, say about 5-10 year, before the price of coated conductor reaches to the same level as the BSCCO wires/tapes. Since most of the power application devices are rather expensive, an international collaboration could be a good idea in order to make the projects more cost effective. The collaboration in applied superconductivity between South Korea and China has been started successfully even as a small size and it is naturally to believe that the collaboration will more successful during the next 5 years.


---------- An article of Dr. Han Zhenghe published in a Korean journal EFFICIENCY SPEED ENVIRONMENT (ESE) No. 06, 2005.5,