Power demands have been mounting around the world. U.S. electricity consumption, for example, has been growing 10 percent per year, while investment in electrical infrastructure has been moving in the other direction, decreasing 5 percent annually. Today’s aging power plants and old technology have managed to handle the rise in demand, but utilities face new challenges including possible greenhouse-gas limits, heightened security, skyrocketing fuel costs, and potential fuel shortages. Simply expanding the existing infrastructure is no longer enough.
“The electrical infrastructure has been on life support for decades, with very little innovation,” says Kurt Yeager, executive director of the Galvin Electricity Initiative, who has authored articles in a number of IEEE journals. However, various groups, including IEEE, already have plans for fixing the infrastructure.
CHANGE Around the world, industry and government groups and foundations such as the Galvin Initiative envision a new, technologically advanced infrastructure. Once it’s installed, tomorrow’s electric power systems should deliver more power, more reliably, and with greater efficiency, wherever and whenever needed. Outages and brownouts should be infrequent, localized, and quickly resolved. Less energy should be lost in generating, transmitting, and delivering electricity, and every conceivable source of electric power should be used.
Many of those goals can be attained, Yeager says, “using our infrastructure better, and using more renewable energy.” However, the intermittent nature of renewable wind power and solar energy requires a great deal of energy backup and storage. “A smart, electronically controlled grid can eliminate much of the backup power requirement, fundamentally improving the cost and environmental performance,” Yeager says.
Most of the necessary technologies are available; a few have already been deployed, and progress is being made on others. But regulatory changes also might be needed. In the United States, the regulatory structure sometimes discourages innovation. On the technical side, control is fundamental. “In today’s grid, power flows the way it wants to flow, and you don’t have much control over which electron goes where,” says IEEE Member Don Von Dollen, chair of the Intelligent Grid Coordinating Committee of IEEE’s Power & Energy Society (formerly the Power Engineering Society). But soon, Yeager says, “digital control of the power grid, with comprehensive electronic sensors operating at the same speed as the power flow, will let utilities reroute power instantly.” Thus, he says, “Utilities will be able to increase existing lines’ power throughput from one-third of theoretical capacity to as much as two-thirds, without exceeding thermal limits or requiring new lines.”
Rates consumers are charged should also depend on the time of day. Smart two-way electric meters can extend digital control to customers, encouraging them to shift power-hungry activities to when demand and price are lowest. The shift, called power shedding, could even be automated, Von Dollen says, with “devices that might decide, from pricing and demand predictions, to cool my house in the morning and then just coast, with little or no cooling through the afternoon.” Some utilities are already switching to smart meters. (Even without such meters, which cost at least US $100 more than traditional meters, many utilities can adjust or cycle users’ air conditioners and other heavy loads to times when demand and rates are lowest.) Italy, Spain, and the Netherlands are aggressively deploying smart meters, Von Dollen says, while France is developing a smart-meter system. Pilot programs are under way in Korea. Meters in Japan and Singapore are relatively advanced.
“This gives the operator another lever to pull if things start getting close to the edge, shedding load only when and where it’s needed,” Von Dollen says. U.S. law now encourages utilities and regulatory commissions to consider power shedding.
Digital electronic control will make the delivery system “self-correcting and self-healing,” Yeager says: “Problems will be islanded rather than cascading. There should be no outages.” And when repairs are needed, utilities can query their power meters to find out what’s needed and where. “Today utilities know in general where work is needed, but not which transformer or which pole. Often they must ask customers where the outage is,” he says.
MICROGRIDS Reliability can also be increased by dividing the power system into microgrids, which are local power networks with a degree of self-sufficiency. A microgrid could be a single home or an area with several small generators, like a university campus. With those resources, Yeager says, “even if something knocks over the power poles, enough power should be available from local generation and storage, possibly including the batteries of plug-in hybrid vehicles, to maintain power service for hours or days. There’s much of this already in Europe, and Tokyo Electric Power is a world leader in the field. But in the United States, the regulated business model makes this harder to achieve.” Although local generators can’t match large power plants’ economies of scale, their proximity to users lets more power get through without the resistive and other power losses that now waste 10 to 15 percent of the power in long-distance transmission lines.
Conservation could help, Von Dollen says. “When electricity is cheap and abundant, you use a lot—the United States uses more per capita than other countries. We need to readjust our thinking,” he says, “and motivate users to conserve.”