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Tony Hwang

wrote:
On Tue, 6 Apr 2010 12:03:40 -0700 (PDT),
wrote:

Just in case this guy was serious:

1) What makes you think DC is cheaper if nobody offers it for sale?
2) Don't blame the people you spoke to on the phone for not knowing
about DC--odds are you were the first person to make this request in
the last 90 years--if ever.
3) I used to work in a NY office building with DC; since that wouldn't
run air-conditioning, they gave us salt tablets. My college dorm was
DC, too, and we had to buy converters to run our stereo and
refrigerator--with the amount of electronics in today's dorms, we
would have been driven crazy.

Even though it's not practical to distribute DC because of the wire
thickness needed as well as losses, in some ways I can see where
there can be some confusion. With DC, the power goes directly to the
device. For example, in a flashlight, the DC batteries send the
electric power directly to the lightbulb (thus the word DIRECT).

With AC, the power goes thru the bulb and is returned to the source
minus what was lost from heating the filament in the bulb (mostly the
loss is from heat). Knowing that, I always wondered just how much of
the electric is returned to the power company in an AC system. Since
that returned power has gone thru our electric meter, does the power
company sell the same electric twice or more times? Maybe there is
some truth in DC being cheaper to the consumer, (not taking into
consideration the much higher costs to distribute it). I have always
wondered what happened to that returned power in an AC system.

Hi,
You sound so SIMPLISTIC! Think basic Ohm's law again and law of energy
conservation. Power(energy) never gets lost for one.

As for safety, I have never experienced a 120volt DC shock. Has
anyone? Is it less painful or harmful than 120v AC? I have no
idea.... I know that a 12VDC car battery can not shock a person, or
at least it's not noticable.