Hi Alfred M. Just my humble opinion here as one who has a working alternative energy system. I used a 48 volt system with 48 volt turbines and solar panel connection. The Turbine voltage must match the battery bank voltage for the controller to operate properly. My reason for going with 48v was to reduce the current requirements of the wiring between system components. Copper is expensive and sometimes a real task to lay it up at distance with heavy gauge wiring. Since wattage is a product of voltage and current, your amp/hour rating is accumulative whether the batteries are series or parallel wired. So, four 12v (or 6 8v) batteries would give you the same capacity regardless of series or parallel connection.......what changes, is the current requirement. Each battery has X amount of current supplied when the turbines charge them, so a parallel connection of four would require 4X current as compared to a series connection that would require 1X current. Best of luck for your system build.
Jon C.
