Wikipedia is not a source of information (by their own definition). Do
not use it for quotes. Now your information is a fourth hand
paraphrasing, lower than a rumour level.

-------
"g" wrote in message ...

On 13/04/2011 17:59, Home Guy wrote:
harry wrote:


What happens to the "say" 1 volt. It is only a local thing because
the utility drops it's output by 5Kw.

I doubt that the regional sub-station is going to do that.

From Wikipedia:
"In an electric power distribution system, voltage regulators may be
installed at a substation or along distribution lines so that all
customers receive steady voltage independent of how much power is drawn
from the line."

Obviously when a local area is supplying power to the grid, power
generation elsewhere will be reduced. And any voltage changes that
results from that will be adjusted with line voltage regulators, if
necessary.




I'm saying that a small-scale PV system is going to raise the local
grid
voltage for the homes connected to the same step-down distribution
transformer.All the linear loads on the local grid will consume the
extra power (probably about 250 to 500 watts per home, including the
house with the PV system on the roof). The extra 250 to 500 watts
will
be divided up between the various AC motors (AC and fridge
compressors,
vent fans) and lights. They don't need the extra volt or two rise on
their power line supply - the motors won't turn any faster and the
lights will just convert those extra watts into heat more than light
output.

How do you get the value 250-500W?

Motors will only increase their energy drain by raising the frequency,
Plus a small loss due to internal resistance in the windings.

As for a resistive load, increasing the voltage from 120 to 125 volt
will result in a power drain increase of about 8.5% or 8.5 W for a 100W
light bulb, assuming 120V is the nominal voltage.

Remember though that the voltage increase on the step-down side of the
transformer due to homeowners PV arrays will be less than 5 volt pretty
much guaranteed. Local codes state a maximum voltage drop (7V in BC)
over the lines to a house, at 80% load of service panel capacity.

Most households have a 200A service panel. A 10kW PV array is well
below
the service panel capacity.

And you cannot just look at the PV array output. You must take into
account the local energy consumers as well. That will reduce the
current
going into the grid, and thus the voltage increase.


The home owner with the PV system will get paid 80 cents / kwh for
the
40-odd amps he's pushing out into the grid, but that energy will be
wasted as it's converted disproportionately into heat - not useful
work
- by the linear loads on the local grid.

You claims are pretty vague, please explain what you mean by wasted.

By the way, there is some "waste" by just using the grid only as well.
Losses everywhere in the grid.


I'm claiming that there won't be a corresponding voltage
down-regulation
at the level of the neighborhood distribution transformer to make the
effort worth while for all stake holders.

What is your definition of worth while? And what do you know about the
utility's voltage regulation policies?

The utilities _have_ to use voltage regulation due to demand changes.