Originally Posted by zjkid
Im turning all my lights off at 8 tonight to raise awareness for global warming.
While this whole turn your lights off at 8pm thing sounds like a great idea, I hope you realize the problems that would happen if everyone does this. Your lights won't just be out for an hour. For the people that don't understand how utilities work, you have to match your supply to your demand. A great deal of time and effort goes in to forecasting load demands for each hour of the day. This is done to insure that there are enough units on-line to cover the load increase, decreases, minimum load of the day, and the maximum load of the day. If everyone shuts off their lights at 8pm, the system voltage will spike due to a sudden increase in supply. Power systems are programmed to react to this by shutting down units on an emergency basis, much like occured during the blackout. When this happens, you have units running at or near their full load and at full pressure, then they suddenly shut off. Safety valves pop, releasing pressure from the system to prevent catastrophic damage to the plants and the turbine. Just like they did during the blackout. If you are lucky, no damage will be done and they can shut the safety valves and restart the plant within 8-12 hours. But, that rarely happens. Something usually breaks which means 24-72 hours of repair time. If the valves don't work right and the turbine overspeeds (it turns at 3600 rpm normally) and the turbine is ruined, it would be at least 2-3 YEARS to get a replacement engineered, built, and shipped from France or China. The worst part would be the blades that can break loose from the turbine and exit the building. Turbine blades have been found over a mile away from a turbine that explodes. Is any of this likely? Probably not, but these are just some of the issues that utilities deal with on a daily basis and work to prevent. So, while these feel good ideas sound great, just stop to thing about the potential impact first... The power grid is fragile enough every day without people intentionally screwing with it.