News Analysis

A Surge of Popularity for Efficient DC Power

In a digital world, why are we still using analog power? That’s the question posed by Brian Patterson, general manager of business development for Armstrong Ceilings and chairman of EMerge Alliance, an industry association that is trying to change the way power is distributed. EMerge promotes the idea that a long-term switch from alternating current (AC) to direct current (DC) for power distribution is crucial to our energy future. EMerge, which includes a variety of members, from Johnson Controls to Herman Miller to Underwriters Laboratories, has started the ball rolling by developing standards for “microgrids” in commercial buildings that allow hybridized use of AC and DC.

In the 1890s a power struggle between Thomas Edison and Nikola Tesla—known as “the war of the currents”—resulted in a standard AC grid. At that time, AC was the better choice, because no one had the technology to efficiently transmit DC power over long distances. Edison stood to make a great deal of money building a large number of small DC power plants, but rural electrification would have been impossible without AC.

Published April 29, 2011