For years, electricity has been transmitted over long distances through alternating current (AC), and has been a staunch rival of direct current electricity (DC). However, recent innovations have led to a new future for DC, and can potentially lead to massive growth in renewable energies. High Voltage Direct Current (HVDC) is promoted by its creators at ABB as being crucial for the transition between fossil fuels and renewable sources, and is predicted to be capable of connecting nations on a massive electric grid.
When electricity was first becoming available commercially, there were massive questions as to which method of delivery would be most effective. Nikola Tesla and George Westinghouse promoted their AC power service, while Thomas Edison headed the DC promotions. AC power was recognized as more effective, as less power is lost over long distances, allowing for power plants to be built far away from residential areas. With DC power, it would have been necessary for a power plant to be built in every city. The infamous War of the Currents ended with AC power being the most popular system for delivering electricity, which it remains to be today. However, the development of HVDC allows for DC power to be sent at high voltages over long distances, which lead to a lower net loss of energy over great distances.
Where many people see HVDC as the future of electricity is the potential for it to form massive grids from several plants, which will help pioneer the growth of renewable energy sources by making the production of energy constant from several plants, with a need for environmentally friendly forms of energy on the rise, this breakthrough can greatly propel humanity into a new future of energy technologies.
However, a major drawback to DC power is a lack of control in emergency situations. If a major power surge occurs in one plant it is more difficult to stop the damage from spreading throughout the grid. This drawback has caused many concerns to be raised for HVDC. However, another major innovation, the HVDC breaker, has solved this issue. The HVDC breaker is essentially a large system of mechanical and electric circuit breaking devices which, in the event of a surge, redirect the flow of electricity disconnect the affected area from the rest of the grid so that repairs can be made without further damage. These developments are major breakthroughs in the delivery of electricity and will revolutionize the industry, at the same time, it will greatly improve the spread of renewable energy and lead to cheaper, safer forms of power.
For further reading check out this article from National Geographic.
Kevin Malloy, Verde Solutions Energy Associate.