4 ms·
Unfortunately I can no longer edit the post, but of course you’re right. Max generated power is proportional to (blade length)^2, therefore quadratic, not expon
by teamonkey 1y ago
Unfortunately I can no longer edit the post, but of course you’re right. Max generated power is proportional to (blade length)^2, therefore quadratic, not exponential.
- kragen 1y agoI assumed that meant that big windmills would be much cheaper per watt than small ones, but according to what I'm finding in https://news.ycombinator.com/item?id=44056971 https://news.ycombinator.com/item?id=44056971, that doesn't seem to be the case. Small rooftop windmills may actually be cheaper!
- teamonkey 1y agoThere’s another limiting factor though, which is that power is also proportional to (wind speed)^3, and the wind is greater higher up. Although having said that, I do believe the main reasons we don’t use them in the UK are noise and wildlife concerns. In many ways the total efficiency doesn’t matter if it’s generating enough power.
- kragen 1y agoYes, so it's puzzling that the small windmills (necessarily designed for low wind speeds) cost less per peak watt. You'd think getting more power per square meter higher up would reduce the cost per peak watt. Wind speeds are more consistent up there, too. The wildlife concerns are completely specious. The main reason you don't use them in the UK are that the wrong sort of people have political power.