A Simple Fix Could Double the Size of the U.S. Electricity Grid

"There is one big thing holding the United States back from a pollution-free electricity grid running on wind, solar and battery power," writes the Washington Post. "Not enough power lines... the nation's sagging, out-of-date power lines are being overwhelmed - slowing the transition to clean energy and the fight against climate change." But experts say that there is a remarkably simple fix: installing new wires on the high-voltage lines that already carry power hundreds of miles across the United States. Just upgrading those wires, new reports show, could double the amount of power that can flow through America's electricity grid... Most of America's lines are wired with a technology that has been around since the early 1900s - a core steel wire surrounded by strands of aluminum. When those old wires heat up - whether from power passing through them or warm outdoor temperatures - they sag. Too much sag in a transmission line can be dangerous, causing fires or outages. As a result, grid operators have to be careful not to allow too much power through the lines. But a couple of decades ago, engineers designed a new type of wire: a core made of carbon fiber, surrounded by trapezoidal pieces of aluminum. Those new, carbon-fiber wires don't sag as much in the heat. That means that they can take up to double the amount of power as the old lines. According to the recent study from researchers at UC-Berkeley and GridLab, replacing these older steel wires could provide up to 80 percent of the new transmission needed on the electricity grid - without building anything new. It could also cost half as much as building an entirely new line and avoid the headaches of trying to get every state, city and even landowner along the route to agree to a new project... If stringing new lines is so easy - and cheap - why hasn't it been done already? Part of the problem, experts say, is that utilities profit more from big infrastructure projects. Routine maintenance or larger-scale upgrades of the electricity grid don't help utilities make a lot of cash compared with building new transmission lines... Duncan Callaway, a professor of energy and resources at UC-Berkeley and one of the authors of the recent study, said that many transmission engineers are not used to thinking of rewiring as one of their tools. "But it's a much faster way," he said. Some changes are already underway to encourage this approach. For a long time, utilities had to undergo lengthy environmental reviews if they were rewiring a line longer than 20 miles. Earlier this month, the Federal Energy Regulatory Commission announced that those would no longer be necessary if utilities are simply replacing wires.

Read more of this story at Slashdot.