You want to do that with the cooler water that is coming back to the power plant after the heat is delivered to the customer. Thus you use lower value heat to m

You want to do that with the cooler water that is coming back to the power plant after the heat is delivered to the customer. Thus you use lower value heat to melt the streets. Assuming you do combined heat & power, as a bonus you get a small benefit on the power cycle as you get colder water into the pwrturbine cooling.