Lately, a return to using low voltage DC power, at least in some applications, had gotten a lot of attention. There was a US workshop sponsored by NEMA, UL and NFPA that drew over 140 participants. A workshop was recently held in Europe that had over 70 attendees. Demonstration installations for data centers and community level distribution have been constructed and tested. A consortium, EMerge Alliance, has developed a standard and applications for using LVDC for office lighting and other purposes and is pursuing requirements for Data Centers.
Some would say that Low-Voltage Direct Current will help save the world, not only improving energy efficiency but enabling improved connection between renewable energy sources and equipment ranging from computers to appliances and from home audio-visual equipment to lighting. In theory, use of LVDC will eliminate many of the power conversions typically imposed when the alternating current provided by the electrical utilities is used to power electronics that operate with direct current. Each conversion results in the loss of energy and reduced efficiency.
The most common renewable energy sources in use today are photovoltaics and wind turbines. The direct current output from these generators is produced without fossil fuels but both need a means to store the energy so that electricity is still available at night and when the wind stops. This energy storage will be one of the keys to whether LVDC becomes more than just a niche application for data centers and similar applications. Other hurdles must also be overcome, including the development of protective equipment to ensure arcing does not cause fires and shock protection when higher DC voltages are used. Standardization is needed to address the various conditions, devices and applications, and it will be critical to establish standardized voltages for which products can be designed.
Smart grid will require the integration of many systems and technologies. LVDC will be a part of the future, the only question will be how significant a role it will play.
For those interested, an LVDC community workspace has been established where events, links to articles and other material and discussions of concepts can take place. Go to LVDC Workspace and sign up (no cost, no spam) to ensure you receive relevant material for this important topic.