If they've raised $100M+, I assume these questions have been asked, but I'm just generally skeptical that the math makes sense.
Having built a 64-turbine windfarm back in the 2000's (so they were likely smaller than they are now) a goodly chunk of the work involved was site prep in building access roads traversable by the cranes required to set everything up, and the massively over-length trailers carrying the blades. Things like maximum grade, radius of the turns, breakover angle etc were hugely important.
Grading out and paving an airstrip when you already have an appreciable contingent of heavy earthworking equipment onsite and, likely, also a concrete batch plant to reduce the travel time for the concrete you're using for the foundations really isn't too big of a stretch!
(It's an honest question; you must have thought of it, of course.)
I'm not saying you are wrong, but by themselves those factors aren't entirely convincing to me.
(Also, the wings need to fold and unfold repeatedly over their lifetime; the blades could just be, in theory, shipped in pieces and then assembled once).
The fact that a custom transport plane and dedicated landing strip for massive wind farms is economically feasible should give you a hint as to what is at stake.
For review, both wind and solar, allegedly with storage bundled in and without subsidies, is cheaper than the next cheapest (and fossil fuel based) generation method: natural gas turbine, per LCOE numbers from Lazard LAST YEAR.
Natural gas turbine is basically topped out in terms of efficiency and cost, I believe they have already exceeded Carnot efficiency with downstream exhaust heat capture and other maximization techniques. They can't go lower. Wind? Likely has a decade of gradual cost improvement. Solar? Successful integration of perovskites might drop prices 50% or more in the next decade, plus usual economy of scale improvement.
The economics are basically settled. The details are massive scale, load leveling, grid adaptation.
In the EU, there's testing facilities that are checking these at this 20 MW size now. Commercially at this point there's up to 17 MW operating in the North Sea.
I'm pretty pessimistic about climate change. But the way wind and solar just keep getting cheaper and better gives me a certain amount of hope.
Wind energy is also getting constantly cheaper, both due to cost reductions and due to making the wind generators larger and thus more efficient. Onshore wind energy is the cheapest in Middle Europe and if they could grow further, costs would go down accordingly.
But even if production can deliver, getting the blades gets more and more difficult, so here we area.
At 150m above ground where there rotor hub sits wind blows all the time.
> Radia estimates the larger turbines could reduce the cost of energy by up to 35% and increase the consistency of power generation by 20% compared with today’s onshore turbines.
Not sure what that translates to in terms of energy output over time.
As for the sibling "Why not airships?" question, the article says:
> Blimps can’t land in windy conditions. Helicopters are more costly than airplanes, and flying with a dangling blade designed to catch wind would prove complex and dangerous.
By comparison a commercial jet takes ~20 years to emit 1 million tons of CO2. https://www.reuters.com/business/aerospace-defense/boeing-je...
You could have used that energy to produce 500000kg * 40MJ/kg * 40% = 8TJ. The turbine would need ~40d to produce this (~25% capacity factor, 10MW nameplate power):
8TJ / (10[MW] * 25% * 3600[s/h] * 24[h/d])
"Simultaneously, Radia is developing a world-class portfolio of wind energy projects to leverage this solution"
So they just need to deliver one of those projects for the carbon to be offset.
As example, for small size and narrow-body planes, in US there are more than 6000 private airstrips, so they could nearly substitute automobiles, but if need landing strip for something large, they are only at very large airports and in special places, like military airbases and space centers, so just few for whole country.
In the world, things are worse than in US, so most Antonov planes was designed to fly from ground road, and carry special equipment on board, but this made them less effective.
Direct-to-tower delivery. Removes the need for transport on the ground for the last miles and the need for a crane.
But large planes need much larger strips, for example typical international airport have strip 30m x 1600m.
Why so much difference, because economy. It is much more effective to make large strips in large cities (or near them), than to make off-road planes (google Bush plane) which will have much more expensive cost to transport weight-kilometer or passenger-kilometer.
From where become expensiveness. Well, most effective planes flight fast at high atmosphere (because speed of sound is significantly higher in low pressure), but they also have high landing speed, and unfortunately, brakes (very similar to automobile) need to dissipate all energy from speed, calculated from simple formula (m*v^2)/2, so with double speed have quadruple energy.
Energy dissipation from plane brakes is really big problem, so big that nearly all big planes have special "thermo-accumulating" weights inside landing gear, which considered to heat fast when braking and then few hours dissipate heat. Extreme example was Concord, on which brakes cooling about 11 hours after landing. Bush planes are slow, so they don't have this problem.
Second problem, because of engineering considerations (physics), large planes usually are tall, but not too wide inside, and very big loads are just considered to transport in "horseman" configuration, mean load placed on top of plane, so need special crane to load/unload.
Of course, problems can scale faster the quadratically, transportation is one of them.
(Also, shouldn't the first order approx should neglect wind speed as a function of height?)
[1] actually worse. From Wiki entry for "Wind Gradient"
"Although the power law exponent approximation is convenient, it has no theoretical basis.[18] When the temperature profile is adiabatic, the wind speed should vary logarithmically with height,[19] Measurements over open terrain in 1961 showed good agreement with the logarithmic fit up to 100 m or so, with near constant average wind speed up through 1000 m.[20]"