These appliances are outfitted with computer chips to help prevent the colossal power failures (brown outs) that plunged large areas of the U.S. into darkness in 2003 and 1996. The chips sense when the electrical transmission system is stressed and partially turn themselves off to save kilowatts. Using these chips in a clothes dryer, traditionally the largest user of residential electrical energy, can turn off the heating element until the grid restabilizes.
The electric grid, a vast network of transmission lines that carries energy from power plants to your home, wasn’t designed to anything more than what it does. We flip a switch or plug something in and generally get as much power as we're willing to pay for. But with the ever increasing demand for more power plants and the growing environmental consequences of providing that power coupled with the rising costs in generating electrical energy this system is unsustainable. As a result, power providers and technology companies are making the electric grid smarter.
In order to convert this passive supplier of electricity into a means of telling us, in our homes, when power demand is high, power companies are testing methods to coax users to reduce their demand during peak periods. One method for cutting back on electrical use is through smart appliances, another is by a glowing amber dot on a light switch that will blink to ask you to turn that switch off.
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. The utility Xcel Energy plans to soon begin a $100 million smart grid project reaching 100,000 homes in Boulder, Colo.
In a separate test that began last September in Milton, situated on the western edge of the Greater Toronto area, 200 test participants are given the ability to use their personal computers to visit an online control panel that configures the home's energy consumption. Each subject chooses the temperature and which lights should be on or off at certain times of the day. Rules can be set for different kinds of days, so the house might be warmer and darker on summer weekdays when the 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.
Programmable thermostats and other "smart home" controls have allowed people control their energy use for some time now. The big change here is the combination of these controls with that blinking amber light on the switch -- where the grid talks back.
Milton's local gas and electricity retailer, Direct Energy, will set those amber dots blinking in an emergency. It might happen a few times in a summer month. Maybe there will be congestion in Ontario's overtaxed transmission network. Perhaps a power plant will be down for maintenance. Or the number of air conditioners in use will overwhelm electric capacity.
If users have not responded quickly enough during times of grid-stress or their individual settings demand that the power company step in then Direct Energy will be able to remotely enforce conservation, should it become necessary. It can raise the set temperature in a participant's home by 2 degrees Celsius in the summer (nearly 4 degrees Fahrenheit), reducing its air conditioning load. The company also has permission to shut off the testers' water heaters and electric pool pumps for four hours at a time during these power emergencies.
Most people prefer this reach of the power company into their homes as opposed to having rolling black-outs. California officials recently had to back away from a proposal to require remote-controlled thermostats in new buildings.
An alternative to the test in Milton is to provide powerful economic incentives to force conservation.
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.
By far the best way to save energy consumption is to have the whole system automatically adjust itself for the highs and lows of electrical use. Controllers are being tested for this purpose. A Demand Controller is a microcomputer load control system that monitors the amount of energy being used in your home and can turn off selected devices until power consumption has lessened. Maximum tolerable loads can be set by the home owner with the highest-conservation setting for dishwashers to start only when electricity prices are at their lowest, or when wind power has kicked on. This can save the home owner 20% to 70% off their energy bill.
Electricity use per home has risen 23% from 1981 to 2001, according to the Department of Energy. Electronics and appliances, and our decreasing tolerance for sweating through the summers are mainly to blame for this increase. The Census Bureau says 46% of single-family homes completed in the U.S. in 1975 had air conditioning. By 2006 it was 89%.
Raw materials that fuel power plants are soaring in price and being eyed more skeptically by regulators concerned about air quality and greenhouse gases. We simply cannot continue to build more coal plants even if they do claim to be cleaner burning. More efficient use of what we already have can be the better answer. A mere 5% improvement in U.S. electric efficiency would prevent 90 large coal-fired power plants from having to be built over the next 20 years, according to Jon Wellinghoff, a member of the Federal Energy Regulatory Commission.
In some states, residents can get rebates if they let the utility trigger radio transmitters on their air conditioners that cycle the chillers off for a few minutes in strained summer hours.
Companies such as EnerNOC have built software and sensor networks that can remotely dim lights or raise refrigerator temperatures inside businesses, in an instant. For homes, upgraded electric meters can offer near-real-time feedback on energy use. And new generations of appliances and thermostats can coordinate with each other and electric meters over in-home wireless networks.
Whatever smart system is adopted, it is sure to be an improvement for both the environment and the home owner.
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