DC to DC converters and DC AC inverters have gotten much cheaper 
and more efficient Ian.  90-95% efficiency is common, and design 
software and circuits are often d/lable for free from the chip 
vendors. 
 
 I have always found 12v adequate for loads below 100 watt, and 
have a 1000w inverter for 200$ which precludes the advantages one 
would get from a 24 or 48 VDC setup. 
 
For windmills, a cheap square wave inverter capable of the max 
mill output with a battery at the tower to buffer the burst output
from wind gusts that feeds a transformer/battery charger at the 
house bank.... may well be cheaper than large guage wire to the 
site of the windmill. 
 
The conversion from DC to any other voltage used to be expensive 
and/or inefficient; no longer, and home designers should... 
 
 My house was wired for 12v throughout, with the inverter feeding 
a few outlets in the kitchen and computer room. I found that to 
be entirely adequate, and much cheaper than locating equipment 
for other voltages. 
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 * OFFLINE 1.58 * I was born without a cluebook! 
--- Maximus 3.01
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