Economical assessment of the scalability of the ground station in pumping mode

[PierreB]

From the publication, in “Power Generation” section:

For the system with four groups

Control: at any time, the working umbrellas of three groups are traveling up, one is traveling down

The total mechanical power transferred to the transmission system is constant at any time

The goal is therefore to have constant generation at the price of a high complexity. But such an installation does not make it possible to reduce the cost of ground stations, whatever the configuration. A large generator or several small connected generators will always have the handicap of:

@PierreB

the tether extension speed, equal to one third of the wind speed

This would be valid both for a single large generator (with an even lower angular speed than smaller generators) and for several smaller generators that are connected or not.

@Windy_Skies

In conventional wind you can’t really connect multiple wind turbines together like that because the rotor goes around the tower.

If it were possible there would be no point. See just above and the quote in the initial post. Another excerpt:

@PierreB

In a conventional design with the tether unrolling from a drum, the drum has low RPM, a high-ratio gearbox is required to increase the angular speed to 1,500–1,800 RPM, as required by conventional electric generators. Thus a large part of the advantage that an AWECS has compared with a conventional wind turbine is offset by the higher cost of the drive train.

You can take all possible combinations and networks, this problem will remain.

Add to this the intermittency of ground stations in pumping mode, leading to wear and stress on the material and electric installation, and you understand that, in spite of the relative success of large kites, there is no pumping mode AWES in the regular market. And I take the risk to state that it is unlikely a significant market occurs in the future. @dougselsam, as our expert in regular wind energy, knew it.