Potential Implications of PHEV’s on the scheduling of Electric Generation Spinning Reserve Bruce Wollenberg

Some basics of power system operation Generation must equal load plus transmission losses (about 5%) Generation must equal load plus transmission losses (about 5%)

Some basics of power system operation What happens if a generator fails? What happens if a generator fails? When load is greater than generation the system slows down When load is greater than generation the system slows down If nothing is done the system shuts down completely If nothing is done the system shuts down completely

Some basics of power system operation We could remove load when a generator fails We could remove load when a generator fails This has been proposed in California This has been proposed in California Generator lost Generator lost Remove large water pumping loads Remove large water pumping loads

Concept of Spinning Reserve Enough generators are not loaded to 100% Enough generators are not loaded to 100% Loss of a generator can be made up with remaining generators Loss of a generator can be made up with remaining generators No load lost No load lost

Spinning reserve Reserve

Spinning reserve

Spinning Reserve

Spinning Reserve costs money Generation companies must be paid to Generation companies must be paid to Run more generators than necessary Run more generators than necessary Lower output on some generators to provide reserve Lower output on some generators to provide reserve Standard electric operation practice is to supply sufficient reserve to withstand loss of the largest generator and the second largest generator Standard electric operation practice is to supply sufficient reserve to withstand loss of the largest generator and the second largest generator

Unique possible contribution of PHEV’s Assume that when the PHEV is plugged in there is also a data connection made to the on board computer in the car Assume that when the PHEV is plugged in there is also a data connection made to the on board computer in the car Assume that future parking garages provide for electrical/data connections for PHEV’s during the daytime hours Assume that future parking garages provide for electrical/data connections for PHEV’s during the daytime hours Control signals can be sent to cars to stop charging, to generate off the car’s battery, to generate using the car’s engine Control signals can be sent to cars to stop charging, to generate off the car’s battery, to generate using the car’s engine

PHEV’s actions in emergency POWER FLOW Charging Step 1: stop charging Step 2: Generate from Battery Step 2: Generate from Car engine POWER FLOW

Numbers Assume 100,000 PHEV’s Assume 100,000 PHEV’s Assume only 5 kW charging or generating per vehicle Assume only 5 kW charging or generating per vehicle Total when stopping charging 500 MW (Mega watts) Total when stopping charging 500 MW (Mega watts) Total additional if generating 500 MW Total additional if generating 500 MW

Extra Costs Power Electronics to take car battery voltage and convert to 120/240 VAC Power Electronics to take car battery voltage and convert to 120/240 VAC Power/data connections in parking garages Power/data connections in parking garages Addition of data connection to power connection in homes Addition of data connection to power connection in homes

The ideal marriage?