DC Systems Initiative at Lawrence Berkeley National Laboratory

Electrical end uses and generation have dramatically changed from the days when Edison and Tesla debated the virtues of DC or AC power. While DC power is often perceived as a radical departure for mainstream electricity distribution, in fact DC power systems have been widely used for a long time in vehicles and boats, and in buildings where DC has long powered traditional telephone service and more recently USB and power over Ethernet. Recently, DC distribution is being implemented in commercial data centers, resulting to significant energy savings. 

380V DC data center (Sun Microsystems)

There are compelling reliability, power quality, and efficiency reasons for using DC power from renewable energy systems or batteries directly in its DC form, rather than converting first to AC and then back to DC for use in the large and growing number of appliances that operate internally with DC.  

Comparison of AC vs. DC distribution power losses between a DC source and a DC load

With both building-sited PV power and DC-based product usage (LED lighting, electronics, DC motors) constantly growing, and given the critical need for improved energy efficiency, it is time to seriously consider DC power for mainstream applications. 

The purpose of this website is to serve as a repository of information related to DC systems and to facilitate research efforts.