[1] Basic grid-friendly devices may incorporate features that work to offset short-term undesirable changes in line frequency or voltage; more sophisticated devices may alter their operating profile based on the current market price for electricity, reducing load when prices are at a peak.
This type of behavior changes frequency from a simple electrodynamic and control systems input to an emergent property.
[4] However, load types such as thermally protected induction motors and power electronics can respond poorly to significant voltage changes.
Participants included local utilities, residential and commercial customers, industrial loads belonging to municipalities, and a number of vendors and researchers.
The grid-friendly technology demonstration showed that common residential appliances did automatically detect grid problems expressed as frequency deviations and reduced energy consumption at critical moments.
The Olympic Peninsula demonstration showed that residential, commercial, and industrial loads did adjust their consumption patterns based on price signals emanating from a distribution-level market operated as a double auction.