Imagine a stretch of open ocean, populated by a swath of wind turbines with skyscraper-sized blades, whipping into the gusts like enormous palm trees. The vision is partly terrifying, partly inspiring, and being taken entirely seriously by the federal government and one of our top research laboratories.
Sandia National Labs has unveiled the preliminary design for a new offshore wind turbine with 650-foot turbine blades. That, as its announcement points out, is twice the size of an American football field. It's also roughly the size of Trump Tower in New York, maybe a more relevant reference point here, since we're talking scale and bluster.
Most conventional wind turbine blades measure over 100 feet, and can generate 1 or 2 megawatts of power. Sandia thinks that by expanding the blade size dramatically, it can increase the amount of energy a windmill can scare up even more dramatically—by as much as tenfold. The lab projects its Trump-sized turbine blades will allow a single towering unit to boast a capacity of 50 MW of electricity. That's like a small power plant, unto itself.
Last year, Sandia was granted nearly $4 million by ARPA-E, the US Department of Energy's blue sky alternative energy research wing, to design and test the concept. "The 50 MW turbine design could enable a 10x increase in power compared to today’s largest production turbines," ARPA-E said in its 2015 funding announcement. "The hurricane-resistant design can enable low-cost, off-shore wind energy for the United States."
It's called the Segmented Ultralight Morphing Rotor (SUMR), and it's notable for reasons besides its massive size.
A SUMR simulation
Basically, SUMR is comprised of turbine blades that are designed to be lightweight, flexible, assembled in multiple segments—as opposed to the heavy, single-serving blades of the conventional design—and hurricane resistant. They're supposed to behave like palm trees.
According to Sandia, "SUMR’s load-alignment is bio-inspired by the way palm trees move in storms. The lightweight, segmented trunk approximates a series of cylindrical shells that bend in the wind while retaining segment stiffness."
And because they're lightweight, the five to seven pieces that form each turbine blade can be more easily shipped and assembled at the point of use. They're also sited downwind, unlike conventional wind farm projects.
Todd Griffith with a cross section of a 50-meter blade. Image: Sandia
More offshore wind is a great idea. The wind blows consistently stronger and more uniformly offshore, but it's expensive to build and maintain massive projects like wind farms out there. That's why there are so few offshore wind turbines in the oceans—they're mostly in European waters—and so hard to stir up interest in more. (The US has but one lonely offshore wind turbine, which researchers are watching in Maine.)
“Exascale turbines take advantage of economies of scale,” Todd Griffith, Sandia's lead blade designer, said in a statement. “The US has great offshore wind energy potential, but offshore installations are expensive, so larger turbines are needed to capture that energy at an affordable cost." He argues that conventional blades are too expensive to manufacture, too heavy to ship and install affordably, for offshore purposes.
The "new blades could be more easily and cost-effectively manufactured in segments, avoiding the unprecedented-scale equipment needed for transport and assembly of blades built as single units," according to Sandia.
There's still clearly a ton of research, testing, and design work yet to be done here, and the SUMR remains a bold, moonshot-scale idea. The kind Trump himself might applaud, if he didn't hate wind turbines so much.