George Tsapoitis displays an electric smart meter in his home in Milton, Ontario. Tsapoitis uses his computer to visit an online control panel that configures his home's energy consumption. He chooses its temperature and which lights should be on or off at certain times of the day.

Milton, Ontario ? The glowing amber dot on a light switch in the entryway of George Tsapoitis’ house offers a clue about the future of electricity.

A few times this summer, when millions of air conditioners strain the Toronto region’s power grid, that pencil-tip-sized amber dot will blink. It will be asking Tsapoitis to turn the switch off – unless he’s already programmed his house to make that move for him.

This is the beginning of a new way of thinking about electricity, and the biggest change in how we get power since wires began veining the landscape a century ago.

For all the engineering genius behind the electric grid, that vast network ferrying energy from power plants through transmission lines isn’t particularly smart when it meets our homes. We flip a switch or plug something in and generally get as much power as we’re willing to pay for.

But these days the environmental consequences and unfriendly economics of energy appear unsustainable. As a result, power providers and technology companies are making the electric grid smarter.

It will stop being merely a passive supplier of juice. Instead, power companies will be able to cue us, like those amber lights in Tsapoitis’ house, to make choices about when and how we consume power. And most likely, we’ll have our computers and appliances carry out those decisions for us.

Done right, the smarter grid should save consumers money in the long run by reducing the need for new power plants, which we pay off in our monthly electric bills. However, if people fail to react properly to conservation signals, their bills could spike.

And certainly a smart grid that can encourage us to conserve will feel different. Envision your kitchen appliances in silent communication with their power source: The fridge bumps its temperature up a degree on one day, and the dishwasher kicks on a bit later on another.

Utilities start projects

Smart-grid technologies have gotten small tests throughout North America, as utilities and regulators scout how to coax people to reduce their demand for power. But there’s little doubt it’s coming. The utility Xcel Energy Inc. plans to soon begin a $100 million smart grid project reaching 100,000 homes in Boulder, Colo.

In Milton, an exurb where dense subdivisions encroach on farm fields, a test with the Tsapoitis family and 200 other households reveals what will be possible – and how much more work needs to happen.

Tsapoitis uses his computer to visit an online control panel that configures his home’s energy consumption. He chooses its temperature and which lights should be on or off at certain times of the day. He can set rules for different kinds of days, so the house might be warmer and darker on summer weekdays when his family is out.

The family can override those changes manually, whether it’s by turning on the porch light or raising the thermostat to ward off a Canadian chill. But the system guards against waste. If midnight comes and no one has remembered to lower the thermostat and turn off the porch light, those steps just happen.

These little tweaks add up nicely for another person testing the Milton system, Marian Rakusan. He’s saved at least $300 on utility bills since the program began in September. Tsapoitis and his wife, Lisa, aren’t certain of their savings but say their 2,400-square-foot home has lower energy bills than a friend’s 1,800-square-footer.

This alone is not revolutionary, because programmable thermostats and other “smart home” controls let people craft similar resource-saving plans. The big change here is the combination of these controls with that blinking amber light on the switch – where the grid talks back.

Remote-controlled power

It appears unlikely that broad swaths of the public will accept remote control from the power company. California officials recently had to back away from a proposal to require remote-controlled thermostats in new buildings.

So a more likely scenario is that consumers will get powerful economic incentives to make those decisions themselves.

Typically we pay a flat rate for electricity, even if sometimes it falls below the actual costs of supplying power at a given moment. In a growing number of places, rates move slightly higher in hours that typically are busiest.

An advanced notion of this will be tested this summer in 1,100 homes served by Baltimore Gas & Electric. Pricing plans will vary, but generally the households will pay the cheapest, “off-peak” rates most of the time. Some testers will pay higher rates every weekday afternoon. And all of them will be subject to “critical peak” periods of even higher charges, declared on as many as 12 weekday afternoons with stress on the grid.

The Maryland utility will have its own version of Milton’s amber dots. Most of the homes will get 3-inch-high orbs that will glow different colors to indicate the price of electricity: red instead of their usual green, for example, during critical peak periods.

Even this will probably be a primitive step.

Eventually, the smart grid will let rates fluctuate even more dynamically, depending on conditions. That already happens in wholesale electricity markets, in which power suppliers buy energy from power producers. Now that would extend to the retail level – our homes. The price of electricity would dip when demand is softest, typically at night or on mild days, and rise in periods of strain.

There’s only one problem. “Consumers are not sitting at home waiting for the latest signal from the power grid,” says Rob Pratt, a scientist with the Department of Energy’s Pacific Northwest National Laboratory. “To get the kind of widespread response that we’d really like to have, keeping it automatic is real important.”

In other words, appliances designed to interact with the smarter electric grid will adjust themselves.

Pratt’s lab has already built and tested controllers that can make it happen. And over the next decade, Pratt expects homes to get appliance controls with a sliding scale. At one end people could choose something like “maximize my ease and comfort.” At the other, “save me the maximum amount of money.” The highest-conservation settings might lead dishwashers to start only when electricity prices are at their lowest, or when wind power has kicked on.

When Pratt and colleagues tested aspects of this in 112 homes in Washington state, they determined the average household’s electricity bills would drop 10 percent.

It says a lot that conservation would be encouraged by the very companies that make money off the use of electricity. But they have no real choice.

Electricity use per home rose 23 percent from 1981 to 2001, according to the Department of Energy. Blame increases in electronics and appliances, and our decreasing tolerance for sweating through the summers. The Census Bureau says 46 percent of single-family homes completed in the U.S. in 1975 had air conditioning. In 2006 that was 89 percent.