On Fri, 12 Apr 2002, Bill Stewart wrote: > Most of the telco business runs on 48V DC, and much of the > "off-the-grid" solar energy electric applications run fine on 12V DC.
Problem with high current and low voltage is that ohmic losses are unacceptably high if you want to transport it more than a few 10 m, and you need big wire crossections (which makes for expensive cables, since usually copper), and if you've got a high resistivity somewhere it heats enough to start a fire. That's the reason photovoltaics tends to use 24 V, not 12 V. > The big advantages of AC are for motors. Many modern motors are smart, anyway, so they can generate their own AC dynamically, internally. Notice that even with photovoltaics there are smart controllers out there which can synthesize AC (whether 110/60 or 220/50) in realtime from individual cell's contributions (there are other kinds, which are still more widespread, but those have higher losses).
