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Default Feeding solar power back into municipal grid: Issues andfinger-pointing

David Nebenzahl wrote:

You are paid 80 cents / kwh for *any* electricity leaving your
array (a billing meter is installed right after your invertors).
It doesn't matter if your own home (AC unit, etc) will suck 100%
of that solar energy with none of it going back into the grid.


and

But still - you can't push more electricity onto a network than
the load is asking for (given that your invertors are functioning
correctly I guess).


Are you sure about that first statement? Pardon me if I misunderstand
what you wrote, but don't you only get paid for the *net current*
leaving your meter? If you're generating 5KW but "sucking" 6KW into
your AC, etc., then you have a 1KW net draw, so you're not gonna get
paid anything, correct?


Under the terms of the Ontario microFIT program, you are paid 80 cents
per kwh for any electricity your project generates and "makes available
to the grid".

For about the first year of the existance of the program, a "behind the
meter" connection was allowable, but at some point last year,
Measurement Canada (a federal gov't department tasked with regulating
commercial scales and other forms of measurement devices) published some
sort of guide or position paper stating their disapproval of this
method.

"Behind the meter" meant that your house retained the same single hookup
to the power mains lines (ie - the grid) and the primary meter be
capable of bi-directional current measurement. The meter measuring the
power output of your PV system (which also had to be bi-directional)
could be connected to the grid through your meter. This is also known
as a "series" connection.

Under the new(er) rules, your revenue meter must make a parallel
connection to the grid (in parallel with your load meter). One result
of this is that you will usually be billed an extra $5 or $10 a month
for having a second service connection to the mains grid - even if it's
the same physical wires carrying both services to your home.

As a load customer, you are billed based on what your primary meter is
reading. As a power generator, you are paid for what your PV meter says
you delivered to the grid. This is (and was) the case regardless how
the revenue meter was connected.

The whole point of the microFIT program is to encourage home owners to
fork out the estimated $35k to $55k to put up 3kw to 10kw PV system on
their roof and contractually garantee them a rate of 80 cents per kwh
for 20 years. You need approval all up and down several layers of
burocracy to get your revenue meter plugged in (the last step of the
process) before you start getting paid.

Alternatively, there is nothing stopping you from installing panels on
your own home and basically hooking everything up exactly the same way
as you would under the microFIT program, except there is no revenue
meter. Your load bill would be the net energy you pulled from the
grid. The payback you would get from your investment would therefore
take much longer.

That second statement is correct: you can't "push" electrons into the
grid. But it doesn't matter *how* your inverters are working; it's a
basic law of physics.


Unless your invertors were set to operate at a slightly higher output
voltage. Even just a few volts differential between the mains voltage
and the invertor output would mean that you could push current out into
the grid, and by doing that raise the local grid voltage slightly.