New answers tagged


Efficiency = heat moved versus energy consumed. For a heat pump this is either SEER or Coefficient of Performance. Heat moved compared to energy used should be around 2 to 5 in equivalent units (COP). SEER includes USA-standard units so it is a larger number, but more or less means the same thing. So you need to measure the heat removed/added - mass ...


to get more power out of the available wind, it is better practice to increase the diameter of the blade disc instead of adding more blades, which greatly increases the size & complexity of the main hub to which the blades are affixed.


Aside from the efficiency, the blades of wind turbines are basically a wing, aerofoil, the actual upwash and downwash zone are much greater than the wing's cross-section. If the blades are too close they can interfere with each other flow stream and actually create debilitating turbulence. The wind turbines are designed to work in a wide range of winds. The ...


The function of the wind turbine is to extract as much as possible energy from the moving mass of air. The energy of a mass $m$ of air is $$KE = \frac{1}{2}m v^2$$ and the power is (because the mass rate is $\dot{m} = \rho A v)$ $$P = \frac{1}{2}\dot{m} v^2=\frac{1}{2} \rho A v^3$$ So, the energy in the air is a function of the velocity. As energy is ...

Top 50 recent answers are included