Wholesale Market 5-min Modal Energy Prices Service Provider Operations Bids Clearing Price Usage Meter Supply Usage Information Home Residential Energy Management System Bids Dispatch System Clearing Price Consumer Display Monthly Bill ~200 Homes on Four Feeders Operations Center Programmable Thermostat Field figure 3. A design overview of the AEP Ohio gridSMART RTP system. rebates a household for the difference between the congested clearing price and the normal 5-min real-time price and provides an incentive payment to a household if its bid was above the normal clearing price but below the congestion MW 10 8 6 4 2 0 150 clearing price. an analysis of the field results indicated that wholesale purchases and household bills reduced by about 5% each. the field data was also used to calibrate simulated household demand-response models for investigating higher penetration levels participants. figure 5 plots the expected response to congestion events on a feeder with 100% rtP household penetration. the dotted line represents a simulation without rtP response and the remaining lines show responses and the rebound for one-, two-, four-, and six-hour congestion events that represent the maximum response using the diversity of thermostat settings seen in the field. Pacific Northwest Smart Grid Demonstration, 2010-2015 the Pacific northwest Smart grid demonstration (PnWSgd) included multiple states and cooperation from Feeder 180 Power Feeder-Rated Capacity Feeder Limit Feeder Power Reduce Feeder Capacity to Engage End Use HVAC Load Oversatisfied Inactive Must Run Active 100 Devices Respond to Price Fluctuations US$/MWh 50 04 05 06 HVAC Units Drop Off RTP PJM Price Constrained Price Price Volatility 500 Units Rebound When Capacity Returns to Normal 12 13 14 15 16 17 18 19 20 21 Hour Feeder 180 Price 18 July 2013 20:30 0 3 Average Indoor Temperature Rises ~4 °F Over Four Hours 0 80 78 76 74 72 04 05 Price Rises to Price Cap 12 13 14 15 16 17 18 19 20 21 Hour House Temperatures, Feeder 180 18 July 2013 20:30 Observed Average Temperature Temperature Average Deviation 5 0 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 ∆F F -3 -5 figure 4. The AEP Ohio gridSMART RTP transactive system in action. 40 ieee power & energy magazine may/june 2016