I think you and @rschmehl and @Ollie could make some estimate.
To start roughing up: on Network Kites and Daisy network kite rotors - #34 by Rodread you made an estimation for a 1 MW single turbine Daisy system: “Rated Torque 231953.8 Nm”, “Rotor Thrust 94500 N”.
The two 8 m span x 0.5 m Tensairity ™ beams of 98 kg each on the bridge supported a load of 3.5 tons. Far better ratios could be obtained as indicated on https://www.researchgate.net/publication/310478916_New_developments_in_Tensairity_and_lightweight_membrane_structures :
Combined to lightweight compression and tension members made of carbon fibre composites live load to dead load ratios of more than 300 can be reached under homogeneous distributed load.
Rings in truss could also be studied.