Wind energy can be valuable in many instances; not necessarily where it is being deployed. Betz limit is often mentioned re wind energy and it is a good indication that people have not read Betz, who mentions the cited limit specifically for single stage, unshrouded propellor type windmills. Betz questioned the bigger is better philosophy. Betz was well aware of the growth of windspeed with height and the fact that efficiency is proportional to the 2/3 power of length (L2/3), but he also knew that cost is proportional to the cube of length (L3), that power density is inversely proportional to length (1/L), and that manufacturing may be much less costly for a large volume of small elements. The benefits associated with reduced scale include manufacturability, transportability, repairability, and more localized placement. Energy is proportional to the square of velocity (V2) and small wind turbines can operate generators at much higher rotational rates and as a consequence require less copper and iron per unit power. Â
Small scale wind can be valuable. The U.S. has a history with small scale wind. Jacobs windmills were rapidly electrifying U.S. farms but were outlawed by government edict during rural electrification.
The messianic focus on efficiency rather than user electricity cost has led to remote placement and greatly increased electricity transport cost.Â
When we read that wind energy is cheaper than fossil fuels it ignores the fact that equal fossil fuel output is required to maintain continuity, that connection to the gid is costly, and that taxpayers and ratepayers will be victimized to pay the increased overall cost.