One of the lesser known approaches to improving energy efficiency and reducing carbon dioxide emissions involves development of a "smart grid." At the cutting edge of this endeavor is the IngelliGridSM program introduced by the Electric Power Research Institute (EPRI).

Sometimes described as the world's largest machine, the North American electrical grid is loaded with limitations, including the inability to both store energy and move energy efficiently (i.e., without substantial energy loss along the way). The grid is also a largely reactive system that does not do a good job of anticipating problems.

In contrast, EPRI states that IntelliGrid would link electricity with communications and computer control to predict and respond to problems before they happen. According to EPRI, IntelliGrid will promote smart energy efficiency systems based on four building blocks:

• Smart and efficient end-use devices that can respond automatically to market signals,
• An integrated communications infrastructure to deliver those signals,
• Innovative rates that reflect changing supply and demand, and
• Efficient electricity markets that support the rate structure.

While IntelliGrid is largely a long-term goal, EPRI notes that the principle is now being applied by several companies. For example, Southern California Edison uses advanced meters with two-way communications to provide customers with information on time-of-use rates and support demand response through direct load control.

Other technologies under development in conjunction with IntelliGrid include high-efficiency end-use devices, Internet protocol addressability for appliances, control systems to optimize device performance, and two-way communications systems that allow automated control of devices in response to pricing or emergency demand-reduction signals.

EPRI is also establishing a research and demonstration program focused on integrating electric vehicles into the electricity grid infrastructure anticipated by IntelliGrid.

More information is available at http://www.epri.com/IntelliGrid.