Dive summary:

• In tests at Iowa State University, engineers want to find the best way to assemble precast concrete elements into towers that could lift power turbines into the more consistent and powerful winds at 100 meters above the ground, a realm where steel towers cannot economically go.
• Professor Sri Sritharan and his team are looking now at the best way to make a tower from six concrete columns and concrete panels, all of which could be transported by conventional vehicles for assembly on-site.
• Putting turbines into the higher air would allow for longer turbine blades, too, and the combination could raise production by as much as 15%.

From the article:

The engineers wanted to see if the segments could handle 150,000 pounds of load, 20 percent over the extreme load at that height. ...