Outside the Box Thinking: Horizontal Wind Turbines

The backers of wind power are running into a big problem. Their ability to generate more power by building ever-bigger wind turbines is running into both physical and economic limits. The problems of scaling up existing wind turbine technology are becoming more evident, as can be seen in this news report from 2022.

A very similar story played out earlier this year just 12 miles away from the site of the wind turbine collapse in the 2022 video.

The physics of today’s most advanced wind turbine technology dictates the nature of the problem:

Larger turbines must face the inescapable effects of scaling. Turbine power increases with the square of the radius swept by its blades: A turbine with blades twice as long would, theoretically, be four times as powerful. But the expansion of the surface swept by the rotor puts a greater strain on the entire assembly, and because blade mass should (at first glance) increase as a cube of blade length, larger designs should be extraordinarily heavy. In reality, designs using lightweight synthetic materials and balsa can keep the actual exponent to as little as 2.3.

Even so, the mass (and hence the cost) adds up. Each of the three blades of Vestas’s 10-MW machine will weigh 35 metric tons, and the nacelle will come to nearly 400 tons. GE’s record-breaking design will have blades of 55 tons, a nacelle of 600 tons, and a tower of 2,550 tons. Merely transporting such long and massive blades is an unusual challenge, although it could be made easier by using a segmented design.

The growing size and mass of the components of a modern wind turbine also limit where they can be built.

Today’s longest blades have become too big to be delivered to inland wind farms. They can be taken only by ship to offshore sites, where building costs are far higher.

Beyond that, the challenge of manufacturing and operating such enormous wind turbines is far costlier than anticipated just five years ago. The designs of the biggest wind turbines are proving to not be up to the task:

Wind turbine failures are on the uptick, from Oklahoma to Sweden and Colorado to Germany, with all three of the major manufacturers admitting that the race to create bigger turbines has invited manufacturing issues, according to a report from Bloomberg.

Multiple turbines that are taller than 750 feet are collapsing across the world, with the tallest—784 feet in stature—falling in Germany in September 2021. To put it in perspective, those turbines are taller than both the Space Needle in Seattle and the Washington Monument in Washington, D.C. Even smaller turbines that recently took a tumble in Oklahoma, Wisconsin, Wales, and Colorado were about the height of the Statue of Liberty.

In April 2024, GE Vernova (NYSE: GEV) pulled the plug on building its largest ever vertical wind turbine because of the technical and economic challenges. That move that is rippling through the wind power generation industry:

The wind industry’s global race to make ever-bigger turbines stumbled to a sudden slowdown last week, jarring U.S. offshore wind projects.

When GE Vernova confirmed that it was canceling one of the largest wind turbines ever designed, it signaled a pause in an arms race that for years had led manufacturers to go higher, longer and wider when building towers, blades and other components. Now, that decision is reverberating across U.S. efforts to build wind projects in the Atlantic.

New York canceled power contracts for three offshore wind projects last week, citing GE Vernova’s decision to abandon its largest turbine model, a massive 18-megawatt machine. The timing could hardly be worse. Offshore wind is the keystone of New York’s plan to generate 70 percent of its power with renewable energy by the end of the decade.

The technical challenges of building and operating ever-larger wind turbines are clearly tied to their vertical form factor. After a certain point, building ever-taller towers to support ever-longer whirling turbine blades comes with exponentially greater costs with too little to be gained from it to make the largest designs practical.

But what if you built your wind turbine with a horizontal form factor? That’s an intriguing concept being advanced by AirLoom Energy’s engineers, which is described in the following video (HT: Core77):

At this point, AirLoom’s horizontal wind turbine power generating concept is intriguing, but unproven. If it proves capable, it would be a game changer for the wind power industry. Since its costs are orders of magnitude lower than what it costs to bring a viable vertical wind turbine design to the market, it would still be worth building prototype units to find out how viable it could be.

That’s outside the box thinking at its best. Lots of potential upside, with limited downside risks. We’ll be following the technology to see how it proves out.