Analyzing the potential impact of low-cost compact fluorescent lamps on a rural distribution system in the Tennessee Valley Authority service territory

Until recently, the use of Compact Fluorescent Lamps (CFL) has been limited due to their cost relative to that of incandescent lamps. Higher lighting efficiencies, reduction in the retail cost of CFLs, and new energy laws are resulting in increased CFL use. Despite the energy savings associated with CFLs, previous research has suggested that proliferated CFL use can potentially lead to degradation in distribution system power quality, specifically harmonic distortion. However, the needs for greater energy efficiency and reduced carbon emissions have consumers and utilities alike foregoing these concerns and encouraging the use of CFLs through various energy conservation programs.;In 2008 the Tennessee Valley Authority (TVA) began its Energy Efficiency and Demand Response initiative. As part of this effort, electric consumers are being encouraged to use CFLs in their homes and businesses. Nevertheless, TVA is concerned about the impact of CFLs on harmonic distortion in distribution systems, particularly in rural systems with relatively high source impedance and predominately residential load bases.;To investigate the potential impact on distribution systems in the TVA service area, field data were collected at residences on a 12.47 kilovolt distribution system before and after retrofit of incandescent lamps with CFLs. These data were used in conjunction with load and harmonic data collected at the system's substation and system capacitor bank states throughout the system to build a harmonic model of the system. The model is simulated and results compared to measured conditions. Worst case scenarios are investigated. The loss of linear resistive load by virtue of incandescent lamp replacement with CFLs poses a significant concern in cases of harmonic resonance.