Technologies Promise Smarter Demand-side Management
Demand-side management (DSM) isn't a new concept—utilities began offering lower rates to customers who could reduce their electricity loads during peak-use periods more than a decade ago. But cheaper microprocessor power and new off-grid resources are creating new options for both utilities and their customers.
Washington, D.C.-based GridPoint began selling a residential-sized power-management system called GridProtect in late 2005, which incorporates a gel-type battery backup unit and all appropriate interconnection equipment. The company's GridConnect product adds the ability to connect distributed-generation supply, such as from photovoltaic panels or a generator, to the rest of the system. The added supply can be used to provide primary power to the home or small business and to recharge the back-up batteries.
In September, the company received venture funding from Cogentrix Energy Inc., a Goldman Sachs subsidiary, to market its technology to utilities. These companies could use the GridPoint products, installed in individual customer locations, as distributed resources during times of peak demand. Participating customers would get reduced rates or other compensation, and, because the equipment would be installed at a customer site, costs could be factored into utility rate bases.
Researchers at the Pacific Northwest National Laboratory are working on a project that could bring this level of intelligence and utility control down to individual appliances. As part of a larger, U.S. Dept. of Energy (DOE) effort called GridWise, researchers are networking water heaters and thermostats in 200 homes located on Washington's Olympic Peninsula. An Internet connection in each home monitors the cost of electricity every five minutes and, based on energy prices and customer preferences, adjusts thermostat and water-heater operations during high-cost periods.
In a second GridWise project, researchers have placed microchips on 150 Whirlpool dryers to monitor the power coming into the appliance. A drop below typical 60-cycle-per-second levels, which could indicate a plant going off line or other power-sapping line difficulties, turns off dryer heating elements until stable frequency levels return.
In addition to studying overall operations, researchers in this project also are looking into whether dropping appliances off the grid over a large area could end up destabilizing the grid further. The microchips are programmed so that appliances turn off and on randomly, rather than all at once, but some studying the effort remain skeptical.
Final results should be available sometime in 2007. If these are positive, the two programs could be combined so that smart appliances could be linked to the Internet, to be activated by pricing as well as power-quality readings.
For more information, go to www.gridwise.org .