ACDC Trends

IEA reported in the World Energy Investment 2020 that COVID-19 led to significant global decrease of energy investment, with the full-year capital expenditure seeing a 1/5 decrease compared with last year, which is around 4,000 billion USD. While electricity, as the second largest energy consumption, is slightly affected. IEA predicted that electricity will become the largest energy expenditure in the near future. Meanwhile, global electricity generation has increased significantly over the past three decades, rising from 11,897 terawatt-hours in 1990 to 26,730 terawatt-hours in 2019. During this period, electricity generation only fell in 2009, due to the global financial crisis.

                                 

                                   Data from: https://www.statista.com/statistics/270281/electricity-generation-worldwide/

This gives rise to the demanding of developing and improving of the electricity transmission technology, which includes new transmission infrastructure development as well as the operation and maintenance of existing transmission systems. There has long been argument and discussion over the AC and DC transmission, and on how to make best use of the different technologies to reduce electricity loss during the transmission, and to achieve economical and environmentally friendly electricity transmission.

Domestically, in the year 2020, an ultra-high-voltage (UHV) line that only transmits clean power, including wind, solar and hydro energy, from northwest China's Qinghai Province to Henan in central China went into operation. As the world's first UHV to transmit carbon-free electricity only, the line could offer as much as 40 billion kilowatt-hours of power annually to central China, reducing 29.6 million tonnes of CO2 emissions. News from: http://www.china.org.cn/china/Off_the_Wire/2021-04/22/content_77431713.htm