Grid securityThe U.S. Needs a Macrogrid to Move Electricity from Areas that Make It to Areas that Need It

By James D. McCalley

Published 5 April 2021

Many kinds of extreme events can disrupt electricity service, including hurricanes, earthquakes, floods, wildfires, extreme heat, extreme cold and extended droughts. Major disasters can leave thousands of people in the dark. During such events, unaffected regions may have power to spare. For example, during the February blackouts in Texas, utilities were generating electricity from hydropower in the Pacific Northwest, natural gas in the Northeast, wind on the northern Plains and solar power in the Southwest. Today it’s not possible to move electricity seamlessly from one end of the U.S. to the other.

Many kinds of extreme events can disrupt electricity service, including hurricanes, earthquakes, floods, wildfires, extreme heat, extreme cold and extended droughts. Major disasters can leave thousands of people in the dark. The Texas deep freeze in February knocked out 40% of the state’s electric generating capacity.

During such events, unaffected regions may have power to spare. For example, during the February blackouts in Texas, utilities were generating electricity from hydropower in the Pacific Northwest, natural gas in the Northeast, wind on the northern Plains and solar power in the Southwest.

Today it’s not possible to move electricity seamlessly from one end of the U.S. to the other. But over the past decade, researchers at national laboratories and universities have been working closely with industry engineers to design an interstate electricity system that can. And President Biden’s infrastructure plan would move in this direction by allocating billions of dollars to build high-voltage transmission lines that can “move cheaper, cleaner electricity to where it is needed most.”

My engineering research focuses on electric power systems. At Iowa State University we have worked to quantify the benefits that macrogrids can bring to the U.S. These high-capacity transmission systems interconnect energy resources and areas of high electricity demand, known as load centers, across large geographic regions.

A National Highway System for Electricity
Dwight Eisenhower had been thinking about a national interstate highway system for decades before he was inaugurated as president in 1953. Eisenhower argued that such a system was “as necessary to defense as it is to our national economy and personal safety.”

Congress agreed and passed the Federal-Aid Highway Act of 1956, which authorized the federal government to pay 90% of the cost of this US$114 billion system, with states covering the rest.

Eisenhower was worried about evacuating cities in the event of nuclear war. The security argument for a macrogrid focuses on extreme events that disrupt the power grid. And the economic argument centers on moving wind, solar and hydro power from areas where they are plentiful to areas with high power demand.

Today the North American power grid is actually five grids, also known as interconnections. Two large ones, the Eastern and Western Interconnects, cover most of the lower 48 states and large swaths of Canada, while three smaller grids serve Texas, Alaska and northern Quebec. Each of these grids uses alternating current, or AC, to move electricity from generators to customers.