So...rule of thumb, the higher the voltage, the more efficient the system.
i don't fully agree with this. there are certainly advantages to higher voltage systems, but i think a better way to state this would be: the higher the voltage creates a better use of copper. (efficient use of spendy wire) if the correct gauge of wire is used, both a 12v and 24 or even 48v system should have the same efficiency.
don't get me wrong, i run a 24v system, and love it! my system is not large enough to justify going to 48v though.
Also - weight to amp;hr rating for batteries is also important...2V are better than 6V are better than 12V by and large...go in series to achieve your voltage rating for batteries (again Volt to power (Ah))...
this is not always true either. some of the best battery manufacturers (rolls) offer true big boy deep cycle batts in 12v. sure they also make 2v and 6v batts.
just giving the new guy a bit of a hard time on the first day of the year...
welcome aboard trbarto!
adam