We have a residential energy program here in Ontario (Canada) that I
really don't agree with (called the Micro-Fit program) where the
electricity from roof-mounted solar panels is purchased by the
provincial power authority (OPA) at something like 80 cents per kw-hour
(a crazy-high fee that will have to be subsidized by somebody - ie the
general population, taxpayers, etc).

I believe all the details for this can be found he

http://microfit.powerauthority.on.ca/

A neighbor of mine had a free evaluation done on his home to see how
many panels situated on his roof would generate how much electricity.

The problem he's facing is that two different levels of power
distribution (the city-owned municipal owned and operated company, and
the provincial or regional power supplier or distributor that either
supplies the electricity to our city or owns the high and medium-voltage
lines and sub-stations where the electricity is stepped down) are
pointing the finger at each other by stating that there is a capacity
problem caused by the other as the reason why his solar panel
installation (which he hasn't yet contracted to be installed) can't be
connected to the grid.

It's my impression that any electricy that he'd be generating would
essentially be 2-phase 208 volts (ie - identical to the service that
enters our homes) and this electricity would simply be inserted or wired
in parallel through a meter to his existing electrical service. I don't
see how the capacity (or lack thereof) of the sub-station serving our
corner of the city plays any role as to whether or not our local grid
can accept and utilize the estimated 5 or 6 kw that his panels are
likely to put out at maximum.

This issue has recently come up as indicated by this:

-----------------
The OPA is proposing that all new microFIT applications submitted on or
after December 8, 2010, would need an offer to connect from their local
distribution company before the OPA issues a microFIT conditional offer
of contract. The proposed rule change can be viewed here.

http://microfit.powerauthority.on.ca...ction-Rule.php
------------------

According to this document:

http://microfit.powerauthority.on.ca...m-Overview.pdf

Page 18 shows the most likely connection scheme - which is to connect
the Microfit PV project to the grid on the customer's side of his load
meter (ie - "behind the meter" - the load meter that is).

My basic thesis here is that I think any argument about the capacity of
the "grid" (where-ever or what-ever the "grid" is) being at or near
capacity and thus the application for eligibility to get the green light
for approval is bogus. We are talking about installations that can't
generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

*We are talking about installations that can't
generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

agreed, this is actually a bureaucratic economics or business problem
and they are trying to call it a technical problem.

It isn't a technical problem.

Mark

On Apr 4, 3:17*am, Mark wrote:
**We are talking about installations that can't

generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

agreed, this is actually a bureaucratic *economics or business problem
and they are trying to call it a technical problem.

It isn't a technical problem.

Mark

The above comment is exactly right.
There is no technical problem. The PV array can be sized to overcome
any supply side issues. What comes in can equally well go out.
But see diversity factor.
http://en.wikipedia.org/wiki/Diversity_factor
This has the biggest bearing on the matter.
Sounds tome that there are politcal/financial matters yet unresovled.

I am having a 4Kwp array fitted to my roof in two weeks time. (UK)
It's just a money thing. I shall have a 12% return on capital.

"harry" wrote in message
...

It's just a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. That's better than the long-term
return of the stock market. There are, however, other factors. I would need to
be convinced that the panels 1) would likely survive a hurricane and 2) their
installation would not damage my roofing system.

Vaughn

On 4/4/2011 4:35 AM, harry wrote:
On Apr 4, 3:17 am, wrote:
We are talking about installations that can't

generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

agreed, this is actually a bureaucratic economics or business problem
and they are trying to call it a technical problem.

It isn't a technical problem.

Mark

The above comment is exactly right.
There is no technical problem. The PV array can be sized to overcome
any supply side issues. What comes in can equally well go out.
But see diversity factor.
http://en.wikipedia.org/wiki/Diversity_factor
This has the biggest bearing on the matter.
Sounds tome that there are politcal/financial matters yet unresovled.

I am having a 4Kwp array fitted to my roof in two weeks time. (UK)
It's just a money thing. I shall have a 12% return on capital.

Keep an eye on your solar array my friend, those things like air
conditioners around here are being stolen at an increasing rate.
People install them at their remote cabins or camps only to return
to a powerless abode. Thieves will steel them while a home owner
is asleep at night!

http://www.usedsolarpowerpanels.com/...ar-panels.html

http://preview.tinyurl.com/3cc3rkl

TDD

On Apr 4, 5:35*am, harry wrote:
On Apr 4, 3:17*am, Mark wrote:

**We are talking about installations that can't

generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

agreed, this is actually a bureaucratic *economics or business problem
and they are trying to call it a technical problem.

It isn't a technical problem.

Mark

The above comment is exactly right.
There is no technical problem. The PV array can be sized to overcome
any supply side issues. *What comes in can equally well go out.

It can equally well come and go provided the distribution system that
is there can handle it. It seems to me that if you have a distribution
system that is already at 100% of it's capacity, then strange as it
may
sound, adding more generating capacity and putting it onto that part
of the system could exceed it's capacity. Now it would seem unlikely
that taken together all the solar panels in that particular problem
distribution system could be generating a net addition to the system
during peak demand. In other words, if it's 100F at 3PM, what would
happen? Would everyone with solar have their AC on and be either
taking power from the grid or at least not giving it back? Or
because
of being paid 80C a kwh to generate electricity, will people be
putting
in large systems and leaving their AC off? If the latter, then it
would
seem to me that taken together enough solar panel systems could
put more power into the distribution system than it could handle.
Certainly given the small penetration of solar, you would not think
a few more would really matter, but at some point, they do start
to add up.

It's also possible that just like with national electric codes there
are
some codes or rules that apply to electric utilities that say in
essence you can't ever allow more than X generating capacity
to be connected to a grid with certain characteristics, regardless
of where it comes from. Could have been put in place before
anyone thought of small solar generators....

Now is that the real reason behind what's going on? Don't know,
but it's certainly theoretically possible.






But see diversity factor.http://en.wikipedia.org/wiki/Diversity_factor
This has the biggest bearing on the matter.
Sounds tome that there are politcal/financial matters yet unresovled.

I am having a 4Kwp array fitted to my roof in two weeks time. *(UK)
It's just *a money thing. I shall have a 12% return on capital.

" wrote:

In other words, if it's 100F at 3PM, what would happen?
Would everyone with solar have their AC on and be either taking
power from the grid or at least not giving it back? Or because
of being paid 80C a kwh to generate electricity, will people be
putting in large systems and leaving their AC off?

Under the terms of the Ontario Microfit program, you (the home owner)
with a (typical) 3kw to 6kw solar array, will be paid 80 cents /kwh for
20 years. The going rate for buying electricity in this market at the
residential level is (when you factor in all the various transmission
and delivery costs) about 15 cents / kwh.

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. In fact, it's probable
that on that hot summer day that your home will still be pulling energy
from the municipal grid - just not as much because of the contribution
from your own panels.

Now is that the real reason behind what's going on? Don't know,
but it's certainly theoretically possible.

There has been some mention of a PF (power factor) issue when it comes
to these panels.

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).

On Apr 4, 1:52*pm, The Daring Dufas
wrote:
On 4/4/2011 4:35 AM, harry wrote:





On Apr 4, 3:17 am, *wrote:
* *We are talking about installations that can't

generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

agreed, this is actually a bureaucratic *economics or business problem
and they are trying to call it a technical problem.

It isn't a technical problem.

Mark

The above comment is exactly right.
There is no technical problem. The PV array can be sized to overcome
any supply side issues. *What comes in can equally well go out.
But see diversity factor.
http://en.wikipedia.org/wiki/Diversity_factor
This has the biggest bearing on the matter.
Sounds tome that there are politcal/financial matters yet unresovled.

I am having a 4Kwp array fitted to my roof in two weeks time. *(UK)
It's just *a money thing. I shall have a 12% return on capital.

Keep an eye on your solar array my friend, those things like air
conditioners around here are being stolen at an increasing rate.
People install them at their remote cabins or camps only to return
to a powerless abode. Thieves will steel them while a home owner
is asleep at night!

http://www.usedsolarpowerpanels.com/...ng-solar-panel...

http://preview.tinyurl.com/3cc3rkl

TDD- Hide quoted text -

- Show quoted text -


I haven't heard about it over here yet. Just a matter of time I
suppose.
However we live in a bungalow so they are not high off the ground.

There is big problems with getting lead stolen off of roofs over here,
mostly churches. Small step to solar panels for the *******s.

I will give it some thought, I never considered the matter. You are
right. Maybe a motion sensor on the roof.

Any one that fits them and gets signed up, gets about $0.65/Kwh for
everything generated whether you use it yourself or not. You get an
extra $0.05 for every Kwh exported. Plus there is what you save off
your electricity bill.
I am having a 4Kwp array, this is the top of the smallest (highest
return band)

If you are retired, you can do a lot of power using activities around
midday on a sunny day.
If you bought an electric car, you could be truely green.

On Apr 4, 12:36*pm, "vaughn" wrote:
"harry" wrote in message

...

It's just *a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. *That's better than the long-term
return of the stock market. *There are, however, other factors. *I would need to
be convinced that the panels 1) would likely survive a hurricane *and 2) their
installation would not damage my roofing system.

Vaughn

Heh Heh. It gets better than that here (UK). The money back is
inflation linked, guaranteed for 25 years. So as the years go by the
return increases.
It's also tax free income.

http://www.fitariffs.co.uk/eligible/levels/

On Apr 4, 12:36*pm, "vaughn" wrote:
"harry" wrote in message

...

It's just *a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. *That's better than the long-term
return of the stock market. *There are, however, other factors. *I would need to
be convinced that the panels 1) would likely survive a hurricane *and 2) their
installation would not damage my roofing system.

Vaughn

We don't have hurricanes here so I dunno about that. You can put as
many brackets on as you like to secure the rails the panels fix to. I
imagine it becomes pointless after a while, the roof is only of
limited strength anyway.

There are many fixing systems,depending on what sort of roof you
have. I went along to the seller's depot and checked them all out
before I agreed to the deal. I was worried about roof leaks.

On 04/04/2011 01:36 PM, vaughn wrote:
wrote in message
...

It's just a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. That's better than the long-term
return of the stock market. There are, however, other factors. I would need to
be convinced that the panels 1) would likely survive a hurricane and 2) their
installation would not damage my roofing system.

Vaughn


Up front - you should in any case arrange for your building insurance to
be extended to include cover for the panels. Why? Because if it does
blow away in a gale or catch fire or whatever and they don't know about
it, in the worst case the insurance could refuse to pay for the damage.
The additional insurance for my roof panels costs here (Germany) €88
per year. There are cheaper offers but I preferred to use the same
company for all the building related insurance to avoid any finger
pointing problems in the event of a claim.
It is possible that the insurer might demand that the roof structure be
checked by a surveyor before you start work. As far as any damage to the
roof during installation, a reputable installation/roofing company
should in any case have professional liability insurance.

On 04/04/2011 03:08 AM, Home Guy wrote:
We have a residential energy program here in Ontario (Canada) that I
really don't agree with (called the Micro-Fit program) where the
electricity from roof-mounted solar panels is purchased by the
provincial power authority (OPA) at something like 80 cents per kw-hour
(a crazy-high fee that will have to be subsidized by somebody - ie the
general population, taxpayers, etc).

I believe all the details for this can be found he

http://microfit.powerauthority.on.ca/

A neighbor of mine had a free evaluation done on his home to see how
many panels situated on his roof would generate how much electricity.

The problem he's facing is that two different levels of power
distribution (the city-owned municipal owned and operated company, and
the provincial or regional power supplier or distributor that either
supplies the electricity to our city or owns the high and medium-voltage
lines and sub-stations where the electricity is stepped down) are
pointing the finger at each other by stating that there is a capacity
problem caused by the other as the reason why his solar panel
installation (which he hasn't yet contracted to be installed) can't be
connected to the grid.

It's my impression that any electricy that he'd be generating would
essentially be 2-phase 208 volts (ie - identical to the service that
enters our homes) and this electricity would simply be inserted or wired
in parallel through a meter to his existing electrical service. I don't
see how the capacity (or lack thereof) of the sub-station serving our
corner of the city plays any role as to whether or not our local grid
can accept and utilize the estimated 5 or 6 kw that his panels are
likely to put out at maximum.

This issue has recently come up as indicated by this:

-----------------
The OPA is proposing that all new microFIT applications submitted on or
after December 8, 2010, would need an offer to connect from their local
distribution company before the OPA issues a microFIT conditional offer
of contract. The proposed rule change can be viewed here.

http://microfit.powerauthority.on.ca...ction-Rule.php
------------------

According to this document:

http://microfit.powerauthority.on.ca...m-Overview.pdf

Page 18 shows the most likely connection scheme - which is to connect
the Microfit PV project to the grid on the customer's side of his load
meter (ie - "behind the meter" - the load meter that is).

My basic thesis here is that I think any argument about the capacity of
the "grid" (where-ever or what-ever the "grid" is) being at or near
capacity and thus the application for eligibility to get the green light
for approval is bogus. We are talking about installations that can't
generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

The bark may be worse than the bite. The company who did my PV
installation also did the entire beaurocratic paperchase for me. They
sent me a whole pile of application forms to fill in, and I sent them
all back with a limited power of attorney to let them get on with it.

I can understand that the grid operators need to know how many PV
installations there are and how they are all connected.

On Apr 5, 2:00*pm, Tom P wrote:
On 04/04/2011 03:08 AM, Home Guy wrote:





We have a residential energy program here in Ontario (Canada) that I
really don't agree with (called the Micro-Fit program) where the
electricity from roof-mounted solar panels is purchased by the
provincial power authority (OPA) at something like 80 cents per kw-hour
(a crazy-high fee that will have to be subsidized by somebody - ie the
general population, taxpayers, etc).

I believe all the details for this can be found he

http://microfit.powerauthority.on.ca/

A neighbor of mine had a free evaluation done on his home to see how
many panels situated on his roof would generate how much electricity.

The problem he's facing is that two different levels of power
distribution (the city-owned municipal owned and operated company, and
the provincial or regional power supplier or distributor that either
supplies the electricity to our city or owns the high and medium-voltage
lines and sub-stations where the electricity is stepped down) are
pointing the finger at each other by stating that there is a capacity
problem caused by the other as the reason why his solar panel
installation (which he hasn't yet contracted to be installed) can't be
connected to the grid.

It's my impression that any electricy that he'd be generating would
essentially be 2-phase 208 volts (ie - identical to the service that
enters our homes) and this electricity would simply be inserted or wired
in parallel through a meter to his existing electrical service. *I don't
see how the capacity (or lack thereof) of the sub-station serving our
corner of the city plays any role as to whether or not our local grid
can accept and utilize the estimated 5 or 6 kw that his panels are
likely to put out at maximum.

This issue has recently come up as indicated by this:

-----------------
The OPA is proposing that all new microFIT applications submitted on or
after December 8, 2010, would need an offer to connect from their local
distribution company before the OPA issues a microFIT conditional offer
of contract. *The proposed rule change can be viewed here.

http://microfit.powerauthority.on.ca...10-December-8-...
------------------

According to this document:

http://microfit.powerauthority.on.ca...m-Overview.pdf

Page 18 shows the most likely connection scheme - which is to connect
the Microfit PV project to the grid on the customer's side of his load
meter (ie - "behind the meter" - the load meter that is).

My basic thesis here is that I think any argument about the capacity of
the "grid" (where-ever or what-ever the "grid" is) being at or near
capacity and thus the application for eligibility to get the green light
for approval is bogus. *We are talking about installations that can't
generate more than 10 kw - and more likely would only generate 5 or 6 kw
on a mid-summer day, with the bulk of that energy being consumed by the
home owner's own AC unit (I'm sure) with little or none to spare to be
injected back into the neighborhood grid.

Comments?

The bark may be worse than the bite. The company who did my PV
installation also did the entire beaurocratic paperchase for me. They
sent me a whole pile of application forms to fill in, and I sent them
all back with a limited power of attorney to let them get on with it.

I can understand that the grid operators need to know how many PV
installations there are and how they are all connected.- Hide quoted text -

- Show quoted text -

Yes, I have all the paperwork to hand. You are not going to get paid
without it!

On Mon, 4 Apr 2011 07:36:22 -0400, "vaughn" wrote:


"harry" wrote in message
...

It's just a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. That's better than the long-term
return of the stock market.

As long as the government can rob peter to pay you.

There are, however, other factors. I would need to
be convinced that the panels 1) would likely survive a hurricane and 2) their
installation would not damage my roofing system.

Vaughn

On Apr 6, 1:45*am, "
wrote:
On Mon, 4 Apr 2011 07:36:22 -0400, "vaughn" wrote:

"harry" wrote in message
....

It's just *a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. *That's better than the long-term
return of the stock market.

As long as the government can rob peter to pay you.



There are, however, other factors. *I would need to
be convinced that the panels 1) would likely survive a hurricane *and 2) their
installation would not damage my roofing system.

Vaughn- Hide quoted text -

- Show quoted text -

It's not taxpayer funded. It's funded by other electricity users in
the UK so ultimately increasing the price of electricity. Still, I
intend to be a receiver of money rather than a giver.

harry wrote:
(...)

It's not taxpayer funded. It's funded by other electricity users in
the UK so ultimately increasing the price of electricity. Still, I
intend to be a receiver of money rather than a giver.

Why does this remind me of the famous Whimpy quote:
"I'll gladly pay you Tuesday for a hamburger today" ?

http://www.urbandictionary.com/

"From Popeye cartoons. Line often uttered by Popeye's portly friend
Wimpy. Of course, "Tuesday" would never come, and so Wimpy
constantly secured himself a free lunch. Thus the line is used to
jokingly indicate that one would like to "borrow" something without
any real intention of ever paying you back."


--Winston

On Apr 6, 10:58*am, Winston wrote:
harry wrote:

(...)

It's not taxpayer funded. It's funded by other electricity users *in
the UK so ultimately increasing the price of electricity. Still, I
intend to be a receiver of money rather than a giver.

Why does this remind me of the famous Whimpy quote:
"I'll gladly pay you Tuesday for a hamburger today" ?

http://www.urbandictionary.com/

"From Popeye cartoons. Line often uttered by Popeye's portly friend
Wimpy. Of course, "Tuesday" would never come, and so Wimpy
constantly secured himself a free lunch. Thus the line is used to
jokingly indicate that one would like to "borrow" something without
any real intention of ever paying you back."

--Winston

I fail to see the analogy.

On 4/4/2011 9:16 AM, Home Guy wrote:
" wrote:

In other words, if it's 100F at 3PM, what would happen?
Would everyone with solar have their AC on and be either taking
power from the grid or at least not giving it back? Or because
of being paid 80C a kwh to generate electricity, will people be
putting in large systems and leaving their AC off?

Under the terms of the Ontario Microfit program, you (the home owner)
with a (typical) 3kw to 6kw solar array, will be paid 80 cents /kwh for
20 years. The going rate for buying electricity in this market at the
residential level is (when you factor in all the various transmission
and delivery costs) about 15 cents / kwh.

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. In fact, it's probable
that on that hot summer day that your home will still be pulling energy
from the municipal grid - just not as much because of the contribution
from your own panels.

Now is that the real reason behind what's going on? Don't know,
but it's certainly theoretically possible.

There has been some mention of a PF (power factor) issue when it comes
to these panels.

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).

One issue that utilities worry about is the available fault current.
The breaker main in a typical home might be able to safely interrupt as
much as 10 kA. The current of a dead short in your home is a function
of the sources feeding it. If the total is less than 10 kA, the breaker
opens and everyone's safe. If the sources could feed more than 10 kA,
the breaker may fuse/melt and the fault will continue to draw current
and your house burns down.

So when adding new sub-station equipment and generating units, they have
to calculate the available fault currents and make sure it's still under
the breaker/protection equipment capabilities.


All that being said, I can't honestly think a small grid-tie PV
installation would make enough of a difference to be a problem. Worst
case is your neighbor has a fault and the combined current from the
utility and your PV setup exceeds his breaker's interrupting capacity.

But a good EE could sharpen his pencil once and do the calcs and
probably find there is a wide margin between what the pole transformer
can supply to a fault and what your PV system would supply. They're
probably just to worried about their liability to bother.

daestrom
P.S. Maybe if every household in a whole development had such a
microFIT installation? I'd have to see the numbers though to believe it.

"daestrom" wrote in message ...
One issue that utilities worry about is the available fault current.
The breaker main in a typical home might be able to safely interrupt as
much as 10 kA. The current of a dead short in your home is a function
of the sources feeding it. If the total is less than 10 kA, the breaker
opens and everyone's safe. If the sources could feed more than 10 kA,
the breaker may fuse/melt and the fault will continue to draw current
and your house burns down.

So when adding new sub-station equipment and generating units, they have
to calculate the available fault currents and make sure it's still under
the breaker/protection equipment capabilities.


All that being said, I can't honestly think a small grid-tie PV
installation would make enough of a difference to be a problem. Worst
case is your neighbor has a fault and the combined current from the
utility and your PV setup exceeds his breaker's interrupting capacity.

But a good EE could sharpen his pencil once and do the calcs and
probably find there is a wide margin between what the pole transformer
can supply to a fault and what your PV system would supply. They're
probably just to worried about their liability to bother.

daestrom
P.S. Maybe if every household in a whole development had such a
microFIT installation? I'd have to see the numbers though to believe it.


-----------------

The fault capacity of a household main breaker or fuses is not an issue,
unless very old technology, like you.
One hundred feet of twisted triplex supply cable limits faults to well
within the fault tolerances.

On a commercial installation or multiple dwelling installation this can be a
problem with main breakers / meters bolted to a huge supply bus or less than
10 feet of conductors but the fault capability spec. requirements are
typically increased to accommodate the huge fault levels available.


mike

On Wed, 6 Apr 2011 00:17:24 -0700 (PDT), harry wrote:

On Apr 6, 1:45*am, "
wrote:
On Mon, 4 Apr 2011 07:36:22 -0400, "vaughn" wrote:

"harry" wrote in message
...

It's just *a money thing. I shall have a 12% return on capital.

I would certainly be tempted by that deal. *That's better than the long-term
return of the stock market.

As long as the government can rob peter to pay you.



There are, however, other factors. *I would need to
be convinced that the panels 1) would likely survive a hurricane *and 2) their
installation would not damage my roofing system.

Vaughn- Hide quoted text -

- Show quoted text -

It's not taxpayer funded. It's funded by other electricity users in
the UK so ultimately increasing the price of electricity. Still, I
intend to be a receiver of money rather than a giver.

There is still a peter being robbed at the government's insistence, dope.

wrote in message
...


dope.

Well, we've degenerated to name-calling. I don't expect we'll see much more
useful discussion from this thread.

Vaughn

On Wed, 6 Apr 2011 21:46:53 -0400, "Vaughn" wrote:


wrote in message
.. .


dope.

Well, we've degenerated to name-calling. I don't expect we'll see much more
useful discussion from this thread.

I can't help it if you don't like facts. harry *is* a dope.

daestrom wrote:

One issue that utilities worry about is the available fault current.


Please be informed that the Josepi clown has been forging my username
for a few weeks now. His provider is doing nothing to stop the forgeries.

Check the headers when in doubt. It's times like these I wonder about
the maturity levels of some, no doubt very ill, people.


mike

daestrom wrote:

One issue that utilities worry about is the available fault current.


Please be informed that the Josepi clown has been forging my username
for a few weeks now. His provider is doing nothing to stop the forgeries.

Check the headers when in doubt. It's times like these I wonder about
the maturity levels of some, no doubt very ill, people.


mike

On Apr 7, 2:46*am, "Vaughn" wrote:
wrote in message

...

dope.

Well, we've degenerated to name-calling. *I don't expect we'll see much more
useful discussion from this thread.

Vaughn

It's all he's got. Just an attention seeker.

In article ,
"Vaughn" wrote:

wrote in message
...


dope.

Well, we've degenerated to name-calling. I don't expect we'll see much more
useful discussion from this thread.

Vaughn

After you have some experience with the group, Grasshopper, you will
discern that calling Harry a dope is a statement of fact and not
name-calling. In fact, dope is letting him off easy.

--
"Even I realized that money was to politicians what the ecalyptus tree is to koala bears: food, water, shelter and something to crap on."
---PJ O'Rourke

On 4/6/2011 19:31 PM, m II wrote:


"daestrom" wrote in message ...
One issue that utilities worry about is the available fault current.
The breaker main in a typical home might be able to safely interrupt as
much as 10 kA. The current of a dead short in your home is a function
of the sources feeding it. If the total is less than 10 kA, the breaker
opens and everyone's safe. If the sources could feed more than 10 kA,
the breaker may fuse/melt and the fault will continue to draw current
and your house burns down.

So when adding new sub-station equipment and generating units, they have
to calculate the available fault currents and make sure it's still under
the breaker/protection equipment capabilities.


All that being said, I can't honestly think a small grid-tie PV
installation would make enough of a difference to be a problem. Worst
case is your neighbor has a fault and the combined current from the
utility and your PV setup exceeds his breaker's interrupting capacity.

But a good EE could sharpen his pencil once and do the calcs and
probably find there is a wide margin between what the pole transformer
can supply to a fault and what your PV system would supply. They're
probably just to worried about their liability to bother.

daestrom
P.S. Maybe if every household in a whole development had such a
microFIT installation? I'd have to see the numbers though to believe it.


-----------------

The fault capacity of a household main breaker or fuses is not an issue,
unless very old technology, like you.
One hundred feet of twisted triplex supply cable limits faults to well
within the fault tolerances.


Got some numbers/calculations to support that? Is that including the
next door neighbors with their PV installation?

daestrom

On Apr 4, 9:16*am, Home Guy wrote:
" wrote:
In other words, if it's 100F at 3PM, what would happen? *
Would everyone with solar have their AC on and be either taking
power from the grid or at least not giving it back? * Or because
of being paid 80C a kwh to generate electricity, will people be
putting in large systems and leaving their AC off?

Under the terms of the Ontario Microfit program, you (the home owner)
with a (typical) 3kw to 6kw solar array, will be paid 80 cents /kwh for
20 years. *The going rate for buying electricity in this market at the
residential level is (when you factor in all the various transmission
and delivery costs) about 15 cents / kwh.

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. *In fact, it's probable
that on that hot summer day that your home will still be pulling energy
from the municipal grid - just not as much because of the contribution
from your own panels.

Now is that the real reason behind what's going on? * Don't know,
but it's certainly theoretically possible.

There has been some mention of a PF (power factor) issue when it comes
to these panels.

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).

Actually you can and do as I understand it. To pump power into the
grid you supply a slightly higher voltage than what is in the line.
When spread over all the loads on the grid the change in voltage is
next to nothing. If enough inputs are made by others the voltage will
rise, and it is allowed to so long as it stays within a certain
range. If it is going to go too high it is up to the utility to
reduce the input at sources they control.

Bruce Richmond wrote in
:

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).

Actually you can and do as I understand it. To pump power into the
grid you supply a slightly higher voltage than what is in the line.
When spread over all the loads on the grid the change in voltage is
next to nothing. If enough inputs are made by others the voltage will
rise, and it is allowed to so long as it stays within a certain
range. If it is going to go too high it is up to the utility to
reduce the input at sources they control.

I have no idea how it works exactly, but here in North Jersey PSE&G has
been putting up solar panels on their (I think) utility poles. Each one
is maximum 200 Watts at 110V, feeding directly into the grid the poles
carry. This is a link + picture in another town not too far away (1 line):
http://www.nj.com/hudson/index.ssf/2..._solar_panels_
o.html
or:
http://tinyurl.com/3dvgy7r

--
Best regards
Han
email address is invalid

On Apr 8, 11:49*pm, daestrom wrote:
On 4/6/2011 19:31 PM, m II wrote:







"daestrom" wrote in ...
One issue that utilities worry about is the available fault current.
The breaker main in a typical home might be able to safely interrupt as
much as 10 kA. The current of a dead short in your home is a function
of the sources feeding it. If the total is less than 10 kA, the breaker
opens and everyone's safe. If the sources could feed more than 10 kA,
the breaker may fuse/melt and the fault will continue to draw current
and your house burns down.

So when adding new sub-station equipment and generating units, they have
to calculate the available fault currents and make sure it's still under
the breaker/protection equipment capabilities.

All that being said, I can't honestly think a small grid-tie PV
installation would make enough of a difference to be a problem. Worst
case is your neighbor has a fault and the combined current from the
utility and your PV setup exceeds his breaker's interrupting capacity.

But a good EE could sharpen his pencil once and do the calcs and
probably find there is a wide margin between what the pole transformer
can supply to a fault and what your PV system would supply. They're
probably just to worried about their liability to bother.

daestrom
P.S. Maybe if every household in a whole development had such a
microFIT installation? I'd have to see the numbers though to believe it..

-----------------

The fault capacity of a household main breaker or fuses is not an issue,
unless very old technology, like you.
One hundred feet of twisted triplex supply cable limits faults to well
within the fault tolerances.

Got some numbers/calculations to support that? *Is that including the
next door neighbors with their PV installation?

daestrom- Hide quoted text -

- Show quoted text -

I think if you had a significant grid connected PV array it might be
possible to cause some very localised problems with the voltage that
could affect your nieghbours. A lot is down to the "inverter" you
have. (It actually does lot more than just invert the supply.)

On 4/4/2011 6:16 AM Home Guy spake thus:

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?

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.


--
The current state of literacy in our advanced civilization:

yo
wassup
nuttin
wan2 hang
k
where
here
k
l8tr
by

- from Usenet (what's *that*?)

On Apr 10, 3:54*am, David Nebenzahl wrote:
On 4/4/2011 6:16 AM Home Guy spake thus:

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?


The 80c per kwh seems very high. But strange as it may seem, here
in the Peoples Republic of NJ, you get paid for the total amount of
electricity the solar array generates, not just the excess amount.
It's not
a direct payment per kwh though. That would be too easy.

The actual story goes something like this. Utilities are being forced
by
law to supply increasing amounts of renewable energy. They can meet
that number through a variety of ways. They could buy it from wind
sources on the grid, for example. But they can also buy certifcates
from folks who generate solar at their homes or businesses. That
certificate counts just like if they had bought energy from company
X's windmill on the wholesale grid somewhere.

Every time the homeowner solar array generates a certain amount
of KWH of energy, the homeowner gets one certificate. Then it
gets more complicated. They have some kind of auction system
that determines how much those certifcates are worth and how
much your power company will pay for it. The amount has
flucutated widely, for factors I don't understand. But in recent
years the typical 8KW array could generate a couplel thousand
dollars a year back to the homeowner.

Oh, and I think they will also actually pay you an additional small
amount for any net amount you put into the grid once a year too.

On Apr 10, 5:40*pm, "
wrote:
On Apr 10, 3:54*am, David Nebenzahl wrote:





On 4/4/2011 6:16 AM Home Guy spake thus:

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?

The 80c per kwh seems very high. *But strange as it may seem, here
in the Peoples Republic of NJ, you get paid for the total amount of
electricity the solar array generates, not just the excess amount.
It's not
a direct payment per kwh though. *That would be too easy.

The actual story goes something like this. *Utilities are being forced
by
law to supply increasing amounts of renewable energy. * They can meet
that number through a variety of ways. *They could buy it from wind
sources on the grid, for example. * But they can also buy certifcates
from folks who generate solar at their homes or businesses. *That
certificate counts just like if they had bought energy from company
X's windmill on the wholesale grid somewhere.

Every time the homeowner solar array generates a certain amount
of KWH of energy, the homeowner gets one certificate. *Then it
gets more complicated. *They have some kind of auction system
that determines how much those certifcates are worth and how
much your power company will pay for it. * The amount has
flucutated widely, for factors I don't understand. *But in recent
years the typical 8KW array could generate a couplel thousand
dollars a year back to the homeowner.

Oh, and I think they will also actually pay you an additional small
amount for any net amount you put into the grid once a year too.- Hide quoted text -

- Show quoted text -

That's more or less what's happening in the UK too.

"daestrom" wrote in message ...

On 4/6/2011 19:31 PM, m II wrote:
The fault capacity of a household main breaker or fuses is not an issue,
unless very old technology, like you.
One hundred feet of twisted triplex supply cable limits faults to well
within the fault tolerances.


Got some numbers/calculations to support that? Is that including the
next door neighbors with their PV installation?

daestrom

-------------------

Sure! Basic Ohms lawa and a wire resistance table

http://en.wikipedia.org/wiki/American_wire_gauge

A 200 ampere service running 240 Vac and only considering the straight
resistance of copper (many use AL outside conductors these days).
and considering the street transformer as an infinite current supply (0 Ohms
impedance)

The chart shows we would use 2/0 copper (assuming solid copper, but it won't
be)

In a 100 feet of overhead run to a house, down the stack and through the
meter to the main panel, where the fuses or breakers are, not considering
the impedance of the overcurrent devices (that allegedly cannot handle a
fault this big) we come up a with a minimum copper resistance of

200 feet (has to return) x 0.07793 x 10^-3 Ohms / foot (oh look ...your old
units too) = 0.015586 Ohms

Using 240 Vac as the fault supply (it won't be under a faulted condition)
the max fault current would be

240 Vac / 0.015586 Ohms = 15.4 kA.

Now we havent figured in any of the other impedances (very generous) and
any approved O/C device in a panel these days is rated at 100kA. The old
"code" fuses were 10kA and no amount of lowering the impedance of the grid
source using a PV generator attempting make it lower than 0 Ohms impedance
is going to increase that fault current. In real life this fault current
would be below 5kA after connection impedances, transformer winding
impedance, primary impedance, ferrous openings, smaller conductors used by
the utility that uses free air rating on smaller conductors, etc.. etc...

Engineering people do not worry about fault currents at residential services
unless special circumstances apply, like within a few feet of a commercial
busbar splitter without enough wire in between. Then they know how to close
their eyes and say "Nobody told me."


Mike

On Apr 10, 3:54*am, David Nebenzahl wrote:
On 4/4/2011 6:16 AM Home Guy spake thus:

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?

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.

If you apply more volts to a line than what it is carrying what do you
think happens? I run machines that use regenerative braking. They
draw energy from the line to set things in motion. To slow or stop
them the electric motor acts as a generator producing a higher voltage
than the grid, forcing power back into the grid. An inverter can do
the same thing using solid state circuits. The inverter in my Prius
takes DC current from the battery and converts it to whatever voltage
and frequency is needed at the time to run the variable frequency AC
motor. When slowing down the motor becomes an AC generator and the
inverter converts the output to a DC voltage just a bit higher than
the battery, pumping charge back into it.

On 4/10/2011 10:02 PM Bruce Richmond spake thus:

On Apr 10, 3:54 am, David Nebenzahl wrote:

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.

If you apply more volts to a line than what it is carrying what do you
think happens? I run machines that use regenerative braking. They
draw energy from the line to set things in motion. To slow or stop
them the electric motor acts as a generator producing a higher voltage
than the grid, forcing power back into the grid. An inverter can do
the same thing using solid state circuits. The inverter in my Prius
takes DC current from the battery and converts it to whatever voltage
and frequency is needed at the time to run the variable frequency AC
motor. When slowing down the motor becomes an AC generator and the
inverter converts the output to a DC voltage just a bit higher than
the battery, pumping charge back into it.

Sorry, I don't think you know what you're talking about.

You seem to think that you can "force" or push "voltage" into a line, by
using a higher voltage than what's on the line.

That's not at all what's at work here when one has a photovoltaic system
and an intertie feeding power back into "the grid".

The intertie and the house's power connection are going to be at pretty
much exactly the same voltage. What happens is that the PV system is
connected *in parallel* with the grid; it's dumping more *current* into
the system, not more voltage.

You do understand the difference between current and voltage, don't you?


--
The current state of literacy in our advanced civilization:

yo
wassup
nuttin
wan2 hang
k
where
here
k
l8tr
by

- from Usenet (what's *that*?)

David Nebenzahl wrote in news:4da29d48$0$26573
:

The intertie and the house's power connection are going to be at pretty
much exactly the same voltage. What happens is that the PV system is
connected *in parallel* with the grid; it's dumping more *current* into
the system, not more voltage.

http://www.northjersey.com/news/116938343
_Municipal_officials_throw_wrench_in_PSE_G_s_solar _paneling_program.html

or
http://tinyurl.com/3tcv4le

--
Best regards
Han
email address is invalid

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.

On Apr 11, 10:28*am, Home Guy wrote:
...
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.-

This explains a lot about inverter technology, though not whether they
use a higher voltage, a leading phase angle or both to force power
into the line:
http://www.solarpanelsplus.com/solar...lar-Panels.pdf

jsw

On Apr 11, 7:19*am, David Nebenzahl wrote:
On 4/10/2011 10:02 PM Bruce Richmond spake thus:





On Apr 10, 3:54 am, David Nebenzahl wrote:

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.

If you apply more volts to a line than what it is carrying what do you
think happens? *I run machines that use regenerative braking. *They
draw energy from the line to set things in motion. *To slow or stop
them the electric motor acts as a generator producing a higher voltage
than the grid, forcing power back into the grid. *An inverter can do
the same thing using solid state circuits. *The inverter in my Prius
takes DC current from the battery and converts it to whatever voltage
and frequency is needed at the time to run the variable frequency AC
motor. *When slowing down the motor becomes an AC generator and the
inverter converts the output to a DC voltage just a bit higher than
the battery, pumping charge back into it.

Sorry, I don't think you know what you're talking about.

You seem to think that you can "force" or push "voltage" into a line, by
using a higher voltage than what's on the line.

That's not at all what's at work here when one has a photovoltaic system
and an intertie feeding power back into "the grid".

The intertie and the house's power connection are going to be at pretty
much exactly the same voltage. What happens is that the PV system is
connected *in parallel* with the grid; it's dumping more *current* into
the system, not more voltage.

You do understand the difference between current and voltage, don't you?

--
The current state of literacy in our advanced civilization:

* *yo
* *wassup
* *nuttin
* *wan2 hang
* *k
* *where
* *here
* *k
* *l8tr
* *by

- from Usenet (what's *that*?)- Hide quoted text -

- Show quoted text -

Not he's got it right except for the fact that allr otating electric
lmachinary is AC.

The modern grid tie/connected "transformerless" inverter manipulates
the DC output from the panels so that they run on their "sweet spot"
ie the most efficient voltage and current. It self connects/
disconnects to the mains as and when there is sufficient light operate
the panels. I t uses the mains sine wave to generate it's own sine
wave on the AC side. The current delivered is indeed dependant on the
output voltage it dleivers to "push2 that current back into the
mains.
Bit on the topic here.
http://en.wikipedia.org/wiki/Kirchhoff%27s_circuit_laws
http://en.wikipedia.org/wiki/Grid_tie_inverter