If all goes according to plan, new technology for constructing taller wind turbines will open up the wind power floodgates in the US Southeast (image courtesy of Keystone Tower Systems).
Wind energy fans have been eyeballing vast swaths of the US southeast for new opportunities, only to be thwarted by relatively thin wind resources and unfavorable political winds, too. Not too much can be done about the latter, but the former problem could be resolved by taller wind turbines that can harvest more optimal wind speeds at higher altitudes. After that, it’s only a matter of time before the political cookie crumbles.
Taller Wind Turbines For Everybody
Designing taller wind towers is not as easy as it sounds. The increased cost for materials, labor, and other elements is just one obstacle. Infrastructure issues stand in the way of transporting larger components, including bridges, tunnels, and winding roads.
On the plus side, taller towers can accommodate longer blades, which enhances the bottom line benefit of harvesting high-altitude winds.
That explains why the US Department of Energy has been on the prowl for taller wind turbine towers. They could be a cost-effective pathway for unlocking new energy resources in Southeastern states and other regions with less-than-optimal wind speeds at lower altitudes.
The Long Road To Taller Turbine Towers: Concrete Edition
Concrete has been used in turbine tower construction for a relatively short period of time, but it could have a game-changing impact on turbine height.
GE is one firm that has been eyeballing concrete to help increase the height of steel turbine towers, without running afoul of transportation issues. The idea is to park a conventional steel tower on a tall concrete column, instead of a slab. To overcome transportation obstacles, the column could be fabricated on site.
Pouring concrete on site could raise new cost issues related to the on-site construction timeline and the cost of labor. GE has been working to step over those hurdles with the the 3D printing firm COBOD and the sustainable building firm Holcim. The result is a modular, transportable 3D-printed concrete system. Once on site, the printer can be tended by a skeleton crew.
What About The Steel Tower?
While GE puts the finishing touches on its 3D concrete system, the Energy Department has been working with the Denver-based firm Keystone Tower Systems on raising the height of steel turbine towers, and last month the agency’s National Renewable Energy Laboratory announced that the company’s new “spiral” welding technology is ready for the commercial market.
“With more than $7 million from the U.S. Department of Energy (DOE), Keystone Tower Systems has developed a solution: a spiral-welding technique, borrowed from the steel-pipeline industry, to build some of the largest turbine towers on the market. Spiral welding is when the steel used to make the tower is curled into a cylinder; essentially, these towers are built from meters-wide steel plates,” NREL explains.
“The technique requires only one machine to construct a tower section, and it can produce towers up to twice as tall and 10 times faster than conventional towers,” NREL enthuses.
As with the 3D-printed concrete system, the spiral welding equipment can be shipped and applied on site, evaporating the transportation issues that bedevil larger components.
“A single machine will use steel shipped flat to the site to complete the joining, rolling, fit-up, welding, and severing for continuous production of tapered steel tower shells. These on-site manufacturing facilities will be able to be deployed on short notice and turn out one megawatt-scale tower per day,” Keystone explains.
Wind Turbines For Everyone
The spiral welding method also cuts the amount of steel needed for the same height. In addition to constructing taller towers, spiral welding could be used to cut the cost of materials for shorter towers, and that appears to be part of the plan.
That raises some new opportunities in the distributed wind field, which is another area of interest for the Energy Department. Distributed wind refers to wind turbines of any size that generate electricity for use on site, for example to power equipment in a factory.
The Energy Department is especially interested in bringing distributed wind turbines to farms, where they could be used to produce green hydrogen for making fuel and ammonia fertilizer among other tasks. The idea would be to relieve farmers from price spikes and supply chain issues for essential goods, by enabling on-site production. Cutting the cost of wind turbines fits neatly into that picture.
Keystone Tower Systems is not letting the grass grow under its feet. The company spent last year revving up its plans for commercial production at a location in Pampa, Texas, and last week our friends over at Wind Power Engineering noted that the factory is indeed up and running.
The initial cohort of 40 employees is already at work on Keystone’s first tower, set for installation at a wind farm in Texas.
More Wind Turbines Coming To The US Southeast, Eventually
That particular tower will apparently be a conventional height, suitable for the rich wind resources in Texas and the midwest. Meanwhile, last summer Denver Post reporter Judith Kohler noted that Keystone already has plans to seek opportunities for its taller towers in the offshore area.
Kohler also picked up on the Southeastern US angle, noting that “The company will use its technology to build towers roughly twice the usual height, around 525 feet, for the Southeast, where the stronger winds are found higher, above the tree cover.”
That’s all well and good for the wind turbines, but our friends over at SP Global are among those noting that policy makers in the Southeast are generally not keen on the idea of renewable energy altogether. A regional transmission operator could help push things along by coordinating renewable energy resources, but the Southeast does not have its own ERCOT, PJM or MISO to lend a hand.
On the bright side, the solar industry has finally begun to break open the bottleneck in Kentucky and several other nearby states, and energy storage stakeholders are beginning to eye abandoned coal sites in the Southeast for “water battery” development. Both of those trends could lend support for planting more wind turbines in the region.
One state to watch in particular is Louisiana, where the solar industry has finally begun to make some serious headway. State policy makers have also begun casting for offshore opportunities for wind development, in the Gulf of Mexico. Among other beneficiaries, the state’s ammonia fertilizer industry could suck up the clean kilowatts to produce a ready supply of green hydrogen.
All of this is by way of saying that the planet-saving energy transition of the future is just beginning to gather steam. The technology is in hand. Now policy makers need to do their jobs and kick things into high gear.