Smart energy grids will be a critical part of a bright green future, making it possible to integrate a wide array of energy sources with varying production levels (from giant wind turbines to home solar to wave power arrays) along with sophisticated abilities to control levels of demand and consumption. Much of the discussion of smart grids has been somewhat theoretical, however, or focused on the back-end systems juggling the connections. What about the home components?
News.com reports on a couple of examples of smart grid components allowing what they refer to as "virtual peak capacity" -- smart consumption controls providing focused consumption throttling, giving energy providers additional capacity to avoid brownouts or blackouts during heavy loads. The value for the energy utilities is capacity when needed most; the value for the consumer (whether at home or in commercial sites) is lower cost:
Depending on the climate control program consumers choose, they can get a monthly rebate or experience an overall reduction of around 15 percent to 25 percent.EnerNOC focuses on commercial buildings; Comverge provides dynamic power management tools to consumers. These tools take advantage of cellular and Internet connections for real-time information about demand, load levels and prices. Since they require communication with the energy grid, these systems are only deployed in locations set up to use them -- but the number of such locations is growing.
The utilities, meanwhile, benefit by not having to build extra power plants or buy energy at peak prices on the open market. In Salt Lake City, a utility is installing Comverge control units in 90,000 homes. Since each unit can throttle about a kilowatt of energy consumption, the units will effectively perform the same job as a 90-megawatt plant, which can cost a few hundred thousand dollars to build.
(Via Sustainability Zone)
Be careful about this, though: a couple years ago, in the California brownouts, there were businesses intentionally using more energy than they needed during normal times, so they could get the financial credits for reducing usage when requested. Payback schemes should be somehow normalized to prior usage or average usage, or measure absolute energy use rather than reduction. (i.e. the utility company won't pay you to reduce your usage 10% at noon, it'll pay you to reduce your usage below 500W/sq.ft. at noon.)