A 5% gain is worth it when you have some severe constraints. If you can just plop down another wind turbine, that 5% almost certainly won't pay off. If you can

A 5% gain is worth it when you have some severe constraints. If you can just plop down another wind turbine, that 5% almost certainly won't pay off. If you can imagine some scenario where you absolutely have to get the most energy out of the wind in a specified footprint, then it would make more sense (and cents). As a counter-example, consider internal combustion engines (ICEs): they have had to get more efficient and cleaner, so you see more and more abstruse dingusses and doohickeys added to them. A 4.5% improvement in ICE efficiency is beyond amazing these days, and would justify well more than a 4.5% increase is cost for the engine.