I've heard of Green Day, where the people of a city/town turn off the appliances for an hour in the evening. How does this help? Like you can't tell the generators to turn off for an hour, all of a sudden. Suppose a city has load of X MW, then if .5XMW appliance is turned off, then where does the other .5MW current go? Also if i turn off the bulb of my house, where does the current that would otherwise light the bulb go?