so.. Summer is comming and i will spend about month in my grandfather village(u can call it farm) so and I with my cousin had been buit something like tree house but just not in tree,near small lake,and sometimes we go there to make camp fire,drink some Vodka or beer ... ok ... so there are no 220V or 110V line,and i want to put litl wind turbine on that 'house" and connect to my bike dynamo, which would work like generator(6V, 3W, so it's 0,5A)so i know that i should take about 15W of wind power,which is about 4-10m/s typical,i would let dynamo this to charge lead acid battery ant day and when we could listen music wia few W amp and have light from LED's of fluorescense lamp :) but i do not know how to calculate size of wind turbine... :( if u can,please help me btw - thanks for GOD that we need no electricity to drink vodka or beer :) :) :)