Our world carries an increasing burden of increasing CO2 emissions. Rather than rationing the use of electric power, we should all together organize ourselves toward a positive solution that benefits growth and a sustainable society. The high voltage direct current (HVDC) technology is a cornerstone that makes it possible to transport sustainable energy to the regions of consumptions that are often far away from the location of generation. Today's commercially available highest HVDC transmission voltage is 800 kV. This system makes use of classic converter stations. The newer HVDC Light technology, Voltage source converters (VSCs) and extruded cable systems, that are commercially available, are characterized today by a highest voltage of 320 kV and 1000–1200 MW of transmission power. This paper describes the need for higher HVDC transmission powers, the general technology of the VSC stations, and an in-depth description of HVDC technology with a focus on extruded cable systems. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.