DC-power grids offer the potential of even greater energy efficiency when combined with LED-based lighting, and several options for implementing DC grids are either available or coming soon, reports Maury Wright.
There is a long-standing debate as to whether we would be better off had Tesla prevailed over Edison, and we had a DC-voltage power grid. Actually the answer isn’t clear cut, but without question a DC grid in a building can increase energy efficiency for many building systems including lighting. Indeed LEDs need DC power, so DC-powered solid-state lighting (SSL) eliminates one lossy power-conversion stage. The technology has become a reality with a proprietary scheme from Redwood Systems that’s widely available and the standardized EMerge Alliance-based products coming onto the market. Moreover, a play from the IT-centric Ethernet networking world may be waiting in the wings.
DC power can provide several benefits, starting with energy efficiency, as we will discuss later. But it offers flexibility as well, such as in flush-mount unobtrusive lighting systems including the T-Bar LED linear fixtures from JLC Tech (Fig. 1). Moreover DC-powered lighting tiles that snap into ceiling or wall grids are headed to market.