American Superconductor Corporation, a leading energy technologies company, and China's Institute of Electrical Engineering (IEE) today announced that IEE has successfully demonstrated a prototype superconductor-based power transformer for the first time in a power grid in China. The transformer was fabricated by IEE in collaboration with TBEA Industrial Transformer Group, the largest transformer manufacturer in China, utilizing high temperature superconductor (HTS) wire manufactured by AMSC. The HTS transformer has operated since November 21, 2005 in a power grid in the city of Changji, Xinjiang Province serving a TBEA manufacturing plant.
Power transformers are utilized in power grids to increase voltage (electrical "pressure") in power lines at generating plants so that electricity may be delivered through power lines to customers with lower energy losses. Transformers are then used again to decrease voltage to more user-friendly levels near customers. Replacing copper wire currently employed in conventional transformers with high efficiency HTS wire reduces the waste of energy inside the transformer due to copper wire's electrical resistance. Another major advantage is the substitution of cheap, environmentally-friendly liquid nitrogen (air is 79% nitrogen) in HTS transformers to provide cooling and electrical insulation for the more expensive electrical insulating oils utilized in conventional transformers. This reduces oil consumption and the risk of transformer fires associated with oil leaks.
The U.S. Department of Energy estimates that the worldwide market for transformers with power ratings over 10MVA exceeds US$1 billion annually, with the fastest growth in sales of transformers occurring outside the U.S. In China, the rate of power consumption increased by 9% in 2001 and continued to increase year-over-year reaching a rate of 14.8% in 2004, according to the China Electric Power Research Institute. The rate of increase of power consumption in the U.S. during the same period was approximately 2% to 3% per year.
According to Dr. Liye Xiao, Deputy Director of the IEE and Director of the Applied Superconductivity Laboratory at the Chinese Academy of Science, this project is an important step in demonstrating the value of superconductor transformers to improve the energy efficiency and reliability of power grids while reducing the amount of oil needed for use as the electrical insulation medium in large, conventional transformers. "Demand for electric power in China continues to grow dramatically year-over-year," said Dr. Xiao. "We need to utilize innovative technologies such as superconductor transformers, fault current limiters and other devices, to guarantee the reliability and stability of our power grids because electricity is an essential ingredient in achieving sustainable economic growth."
"This demonstration project is a critical step on the path to the development of practical, commercial superconductor transformers in China -- a market we believe will be very large," said Greg Yurek, chief executive of AMSC. "China represents one of the fastest growing markets for superconductor transformers. This is because the demand for electricity continues to rise very rapidly and because energy efficiency is becoming increasingly important in China."