Consider that the whole electrical system - the grid - has to be sized to meet that peak demand. Nobody wants to flip the switch and not have the lights come on.
Right now, nearly 50 percent of the power supplied to this region's grid, which encompasses all or parts of 13 states and the District of Columbia, comes from coal-fired power plants. Many of them are decades old and are major polluters.
Faced with tightening federal regulations, many will have to make expensive upgrades or shut down.
Last week, GenOn Energy announced plans to retire seven coal-fired power plants, including five in Pennsylvania.
One of them, the Portland Generating Station on the New Jersey border, has been embroiled in legal wrangling.
New Jersey officials said the plant was polluting their air, and the federal Environmental Protection Agency ordered it to reduce its emissions.
Bruce Nilles, senior director of the Sierra Club's "Beyond Coal" campaign, called the GenOn announcement "a win for public health."
But it will be difficult to retire these plants if there isn't enough power to feed the grid. Reliability trumps everything.
The grid operator, PJM Interconnection, based in Valley Forge, studies the potential effects of shutting down plants. In the past, when problems were predicted, the owners agreed to keep the plants online until the problem could be solved.
Case in point: Exelon's Eddystone and Cromby coal-fired generating stations in Delaware and Chester Counties delayed their shutdown dates.
At its simplest, we can't let go of the older, polluting coal power plants until we replace them with other plants, which is happening. Or until we consistently, and predictably, reduce the peaks.
Which is how I have this notion that my washing machine might be helping.
So I called PJM to ask.
"With all due respect to your washing machine, your air conditioner is more important," said Susan Covino, senior consultant of emerging markets.
In this region, the highest peaks come on hot summer afternoons, when the air-conditioning is cranking.
Last year, the highest demand was 158,043 megawatts on July 21 at 5 p.m.
The lowest demand, the valley, was 50,645 megawatts, on April 24 at 5 a.m.
Not that you could move any of July's appetite to April, but still, that low ebb of use was a third of the peak.
These peaks are so important that major attempts are being made to shave them.
When it comes to households, one example is the Peco plan that pays residents $30 a month for the four hottest months - $120 total - if they give the company permission to remotely cycle their air conditioners on and off when needed.
Manufacturers are developing smart appliances - for example, refrigerators that will defrost only at night, a time of low electricity use.
One day, smart devices will orchestrate a household's consumption. Say my refrigerator has to run for 15 minutes every hour to keep the food cold. And my hot-water heater has to run for 15 minutes as well.
No need for both to run the same 15 minutes. A smart meter could cycle them.
Cellphone companies have figured out that the way to manage customer demand is to charge higher rates during peak hours. Sooner rather than later our household electricity will be billed this way as well.
PJM provides "pricing signals" every five minutes, and the goal is to make residential customers, and their smart devices, privy to this information. When the price is right, the water heater might awaken from a self-induced slumber.
There is ample opportunity here. Residences account for 38.7 percent of the nation's electricity use, more than any other sector.
But until all these automated devices are widely available, manual power management is where it's at.
Joseph Otis Minott, executive director of the Clean Air Council, agrees there's potential for me and my washer, if only in the simplest sense.
"If you got in the habit of doing that, and if you could persuade any number of other people to do that," and if it was a reliable enough shift for PJM to trust that the reduction was real, and not a blip . . . "then it could have an impact," he said.
So while my washer is a little ripple, with many more and much bigger ripples needed, it still makes me feel virtuous. Even slighty subversive.
And look out, grid. My dishwasher has a timer, too.
"GreenSpace" appears every other week, alternating with Art Carey's "Well Being" column. Contact Sandy Bauers at 215-854-5147, sbauers@phillynews.com, or follow on Twitter @sbauers. Visit her blog at www.philly.com/greenspace.
