Posted by Big Gav in smart grids
Lester Brown has a post on smart grids at TreeHugger - Smarter Grids, Appliances, and Consumers.
More and more utilities are beginning to realize that building large power plants just to handle peak daily and seasonal demand is a very costly way of managing an electricity system. Existing electricity grids are typically a patchwork of local grids that are simultaneously inefficient, wasteful, and dysfunctional in that they often are unable, for example, to move electricity surpluses to areas of shortages. The U.S. electricity grid today resembles the roads and highways of the mid-twentieth century before the interstate highway system was built. What is needed today is the electricity equivalent of the interstate highway system.
The inability to move low-cost electricity to consumers because of congestion on transmission lines brings with it costs similar to those associated with traffic congestion. The lack of transmission capacity in the eastern United States is estimated to cost consumers $16 billion a year in this region alone.
In the United States, a strong national grid would permit power to be moved continuously from surplus to deficit regions, thus reducing the total generating capacity needed. Most important, the new grid would link regions rich in wind, solar, and geothermal energy with consumption centers. A national grid, drawing on a full range of renewable energy sources, would itself be a stabilizing factor.
Establishing strong national grids that can move electricity as needed and that link new energy sources with consumers is only half the battle, however. The grids and appliances need to become "smarter" as well. In the simplest terms, a smart grid is one that takes advantage of advances in information technology, integrating this technology into the electrical generating, delivery, and user system, enabling utilities to communicate directly with customers and, if the latter agree, with their household appliances.
Smart grid technologies can reduce power disruption and fluctuation that cost the U.S. economy close to $100 billion a year, according to the Electric Power Research Institute. In an excellent 2009 Center for American Progress study, Wired for Progress 2.0: Building a National Clean-Energy Smart Grid, Bracken Hendricks notes the vast potential for raising grid efficiency with several information technologies: "A case in point would be encouraging the widespread use of synchrophasors to monitor voltage and current in real time over the grid network. It has been estimated that better use of this sort of real-time information across the entire electrical grid could allow at least a 20 percent improvement in energy efficiency in the United States." This and many other examples give us a sense of the potential for increasing grid efficiency.
A smart grid not only moves electricity more efficiently in geographic terms; it also enables electricity use to be shifted over time--for example, from periods of peak demand to those of off-peak demand. Achieving this goal means working with consumers who have "smart meters" to see exactly how much electricity is being used at any particular time. This facilitates two-way communication between utility and consumer so they can cooperate in reducing peak demand in a way that is advantageous to both. And it allows the use of two-way metering so that customers who have a rooftop solar electric panel or their own windmill can sell surplus electricity back to the utility.