Keystone Tower Systems will expand its presence in the wind industry with its patented spiral-welded steel towers.
Keystone’s tapered spiral-welded technology can significantly drop the cost and time to build both onshore and offshore towers, adding strength and saving steel versus traditional can-welded towers. Its towers will enable turbines to reach higher heights for stronger winds while solving transportation constraints and opening new regions to wind power.
“Scaling up automated spiral welding of taller towers will support the wind industry’s next phase of cost reduction and growth as we map onto the need to drive the electricity sector toward net-zero goals,” said Steve Lockard, Keystone’s Chairman of the Board.
Denver-based Keystone has over 100 patents in 30 countries born from research that cofounders Eric Smith and Rosalind Takata started after meeting at MIT. Searching for innovations that could dramatically increase the cost-effectiveness of wind power, they developed a way to tailor the spiral-welded technology already proven in the pipe industry to the wind industry.
“Spiral welding makes possible a new level of automation, resulting in faster production and higher quality,” said Smith. “The result is a tower that can be built 10-times faster than conventional towers, cost-effectively reach heights of 160 meters and beyond, and can still be installed with existing cranes and identical interfacing with turbine hubs.”
A successful sub-scale demonstration project has been in operation since 2015. In 2019, the company secured Series B financing and is nearing completion of its first scale factory in Pampa, Texas. By 2023, the company plans to offer the option of cost-effective tower fabrication on-site for wind farms across the country.
Keystone was awarded up to $5 million by the U.S. Department of Energy in 2019 to develop mobile manufacturing equipment that can make spiral wind towers at the site of onshore wind farms. This avoids transportation constraints that limit can-welded towers to sizes that can be moved on a highway.
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’s technology is enabling the potential of taller towers to which the National Renewable Energy Laboratory has devoted years of research, culminating in the May 2019 report, “Increasing Wind Turbine Tower Heights: Opportunities and Challenges.”