The smart grid is an electrical grid that communicates. The idea is that the Internet and communications technology can make our electrical system far more resilient to problems like blackouts, better accommodate unconventional power sources, and ease energy demand by providing instant information about prices to consumers.
Public investment in smart-grid infrastructure has ballooned over the past several years. The charge has so far been led by the U.S. and China. In 2009, the U.S. government set aside $4.5 billion as part of a larger economic stimulus package to fund projects designed to modernize the grid and deploy smart technologies. China has also committed billions of dollars.
Renewable energy is a key driver of the smart-grid idea. Although wind turbines and solar panels still generate only a tiny fraction of the world’s electrical power, the installed capacity of the two energy sources—the total potential electricity that can be generated—is increasing rapidly. A grid dependent on large amounts of wind and solar power must be able to adapt to sudden changes in power supply, such as when the wind dies down near a wind farm. That will create new demands for tighter digital monitoring and control over electrical systems.
A smarter grid will employ an array of devices monitoring conditions in real time; that will help integrate new power sources and also avoid blackouts, which can cause billions of dollars in economic damage. One such device is called a phasor measurement unit, or PMU. As of 2011, about 150 such devices sat at strategic points on the North American power grid taking detailed measurements of electrical waves at a rate of 30 times per second, much more often than conventional equipment. The data can be time- and location-stamped using GPS technology, allowing information from multiple utilities to be combined and synchronized into a high-resolution picture of conditions across the grid.
Jeff Dagle, senior electrical engineer at Pacific Northwest National Laboratory, likens the change to upgrading from x-ray pictures to MRIs. In the next 20 years, the Electric Power Research Institute expects utilities to install around 1,250 more PMUs around the U.S. and Canada.