[rescue] SGI Challenge L systems available in Denver

[Francisco Javier Mesa-Martinez]

On Fri, 17 Sep 2004, Sandwich Maker wrote:

> " From: patrick at mail.zill.net (Patrick Giagnocavo)
> "
> " On Fri, Sep 17, 2004 at 10:57:00AM -0400, Nathan Raymond wrote:
> " >
> " > What's really needed is a large AC->DC converter in the basement and new
> " > DC outlets alongside AC outlets in houses, and devices that work with the
> " > []
> "
> " I was doing some reading on solar power, and this is a hot topic in
> " that community.  Basically where feasible run DC straight from the
> " battery bank, only using AC where necessary.
> "
> " The problem with DC is its perceived danger, and that you need thicker
> " wires for running large loads.
>
> depends on the voltage.  110vdc doesn't need any thicker wires than
> 110vac, but i assume you must mean 12vdc.

The thickness of the wire has nothing to do with the voltage differential,
you could have 1000V on a hair thin wire: It is them Amps that matter :)
Electrical energy losses are directly proportional to current flow, not to
the energy flow.

The reason for using AC is very simple: It is easier to genreate alternate
current, and AC can be easily stepped up or down. The low voltage/ hight
current generated can be stepped up to high voltage/low current for
transmission (lower loss when the current is smaller), and then it can be
stepped back to low voltage/high current at the destination point. Plus
you can also play with the phase in order to adapt for long distance
distribution, something that can not be done with DC.