Mass-market electricity customers’ behavior accounts for one-quarter to one-third of home energy use. Research over the past two decades has documented that useful feedback can result in reductions in energy use of 4 to 15 percent. Moreover, feedback is more useful when it is immediate and easily accessible rather than antecedent; e.g., provided with the monthly bill). Even monthly information, though, is useful, especially if the customers previously hadn’t received any feedback other than the amount owed for the utility bill. But for dynamic electricity pricing, timely feedback is essential. As part of the Information Display Pilot (IDP), Primen investigated devices for displaying dynamic pricing signals and immediate energy use and cost information.