Load-shape data for residential lighting: Survey results for incandescent and compact fluorescent lamps

Understanding the load pattern created by compact fluorescent lamps is key to evaluating the impact on the utility's system peak demand and calculating energy savings. A household survey was distributed to consumers involved in a Danish CFL programme. The primary goal was to map the daily patterns of CFL and incandescent lamp use in the residential sector throughout the year. A secondary aim was to evaluate consumers' acceptance of the CFLs. Two CFLs were offered free of charge to each of the utility's 240,000 residential customers. The participation rate was 90% (1.8 CFLs per home). Although this represents only 7% of the total number of lamps per home, the CFL's long burning hours accounted for nearly 20% of the total burning time of all lamps. Total annual household electricity savings consumption for lighting due to the CFLs is approximately 15%, or 125 kWh per home. During afternoon peak hours on winter days, up to 80% of the CFLs are in use. During the morning peak hours, however, only 30% of the CFLs are in use.