Harold and Susan Vordos wrote:
"Artemia Salina" wrote in message
news
On Thu, 15 Sep 2005 12:04:56 -0700, Harold and Susan Vordos wrote:


3 phase is always on a demand meter here.

I've seen the term "demand metering" mentioned here several times
and have gleaned that it can be expensive for some reason. What is
demand metering and why is it more expensive than other types of
metering?

(My dream is to sell my house when I retire and live in a shop
which will have 3 phase power from the util. co.)


As I understand it, the meter monitors the sustained gross current drawn for
a given period of time. If you go over a prescribed amperage (here, it's
50 kw), you are charged a higher amount for all of your consumption for that
billing period. You must sustain the draw for something like 15 minutes
in order to set the meter, so simply starting a large motor, for example,
doesn't reset the meter. Because I don't have my induction furnace in
operation yet (it's a 50 kw unit itself), I haven't come close to exceeding
the demand.

Right.

The short-term reason is to reduce peaks
so that the utility doesn't have to bring
another generator on line or buy power
from another utility.

The long-term reason is so that the utility
doesn't have to make capital investments
in lines and plant that will only be used
a couple of hours a day.

The utilities have taken it a step further
in some areas. They will give certain industrial
customers a discount on all their power if
they agree to cut their load upon request.