Edison revisited: Impact of DC distribution on the cost of LED lighting and distributed generation

This paper models the case of a new construction 277 V commercial lighting system, one of the many possible applications of a DC distribution system, using fluorescent and LED fixtures in a conventional AC circuit and in a DC lighting circuit. The levelized cost of lighting for the AC fluorescent, DC fluorescent, AC LED, and DC LED cases are calculated for projected LED and solar PV performance parameters, and a variety of DC bus voltages incorporating its impact on fluorescent ballast and LED driver efficiencies. Results show that with present fluorescent and LED efficacies, fluorescent lighting systems are the lowest annualized cost lighting option. However, if one has decided to install a DC distributed generation technology such as solar PV due to environmental policy, new-construction DC LEDs will be the lowest (annualized) cost lighting option by about 2012.