Hi Baldy, WRT wind turbine efficiencies the amount of energy...

Hi Baldy,

WRT wind turbine efficiencies the amount of energy harvested from the air per m² of disk area cannot get much more improvement. The physical maximum (Betz limit) is 59.3% yield of total energy held by the wind (assuming absolutely no losses!), new wind turbines are pushing low 50%'s and have been stable at this benchmark for years.

This limit however only reflects the power output / m² of disk area, and thus wind turbines will produce more electricity the larger they are. Theoretically there is no upper limit to how big a turbine can be, however, physically we are limited to material properties & costs, and space big enough for the blades.
As more advanced materials and manufacturing techniques come to market you can expect wind turbines to grow in size and power output, however it will soon reach a diminishing return whereby an investor would be better off building a second turbine than gaining a marginal increase in disk area.

The free market will constantly invest in the turbines that provide the lowest LCOE, which is individually calculated for each turbine & site. There are plenty of engineers in the industry who are paid a lot of money to work out the economic trade offs between placement & size of a turbine. Offshore fields can afford to have bigger turbine blades as it costs them less to transport the larger blades and the power output is more stable (higher constant winds).