In short, we can't extract more than about half of the available wind energy, no matter what the design.
This is because if all kinetic energy is extracted, the air would no longer be moving behind the windmill, so it would stop turning. Betz's law is the optimum compromise between extracting energy and sufficient airflow to keep the windmill rotating.
In short, we can't extract more than about half of the available wind energy, no matter what the design.
This is because if all kinetic energy is extracted, the air would no longer be moving behind the windmill, so it would stop turning. Betz's law is the optimum compromise between extracting energy and sufficient airflow to keep the windmill rotating.