Rooftop Pv installers in Sydney area

[Davo]

Sylvia Else wrote:

I don't see any proposals to subsidise domestic coal powered generators,
nor to let consumers sell power from their domestic coal powered
generators back to the grid at inflated prices.

Sylvia.

Verve Energy in Western Australia is about to be subsidised to the tune
of $700 million. They have been made, by law, to sell their electricity
at below cost. Having run up a huge debt the state government has to
bail them out. You can build your own coal fired generator and sell it
to Western Power for 10/11 of what you would otherwise pay for it. At
quantities above 1 megawatt you can negotiate better rates.

 

[Davo]

Sylvia Else wrote:

Davo wrote:

The backup issue is a load of wank, since solar cell owners will be
drawing on the grid when demand is low, such as night time. Coal fired
generators are at their maximum efficiency under full load, anything
less is losing money.

Coal fired stations run pretty much at full power all the time anyway,
because they have the lowest marginal cost. But they're also expensive
to build, so they don't get built unless the baseload power demand
ensures that they'll be able to run all the time.

It's natural gas and other types that are brought on and off line as
demand varies.

The backup issue arises because there has to be capacity available in
the system to supply power to the owners of PV cells whenever the latter
happen not to be generating power.

Another way of seeing how this impacts on electricty costs is to
consider the effect that the existence of PV cells has on generation
investment decisions. Because the cells displace generating capacity
when the sun is shining, they reduce the proportion of the time that
generating capacity is used. This shifts investment decisions towards
plant that has a lower capital and higher operating cost. The total cost
of power from such plant is higher, and that higher cost has to be born
by the power consuming community.

Sylvia.

I only know about the West Australian grid where the base load is
determined on economics, and gas, being cheaper than coal, will be burnt
before coal. Gas gets a pretty good deal in WA due to various historical
political reasons. So when the load drops it's a battle between the coal
fired generators to see who gets dropped off. The so called "back-up
issue" isn't an issue because there's plenty of spare capacity at night
when industry is sleeping.

 

[Davo]

Sylvia Else wrote:

terryc wrote:
On Wed, 25 Mar 2009 12:09:02 +1100, Sylvia Else wrote:


Coal fired stations run pretty much at full power all the time anyway,


Err, AFAIK, they do not. It isn't unusual for a significant amount of
capacity to be off line for maintenance. In fact, it is essential for
reliability.

Full time when they're available to be scheduled. Other capacity spends
much of its time available to be scheduled, but off line, because its
marginal cost of operation exceeds that of the coal fired plants.

Sylvia.

It's desirable as a producer to run at full capacity but it's the spot
market that determines who actually runs. The customer wants the
cheapest energy and doesn't particularly care about the producers
problems. In fact producers in Western Australia get fined tens of
thousands of dollars per hour for unscheduled outages, and that's in
addition to having to pay another supplier to cover your shortfall.

 

[Sylvia Else]

Davo wrote:

Sylvia Else wrote:
terryc wrote:
On Wed, 25 Mar 2009 12:09:02 +1100, Sylvia Else wrote:


Coal fired stations run pretty much at full power all the time anyway,


Err, AFAIK, they do not. It isn't unusual for a significant amount of
capacity to be off line for maintenance. In fact, it is essential for
reliability.

Full time when they're available to be scheduled. Other capacity
spends much of its time available to be scheduled, but off line,
because its marginal cost of operation exceeds that of the coal fired
plants.

Sylvia.

It's desirable as a producer to run at full capacity but it's the spot
market that determines who actually runs.

It is, but only a deranged gas-fired plant manager bids prices below his
marginal cost of operation, and only a similarly deranged coal-fired
plant manager bids prices above the marginal cost of gas-fired plant
when it's unlikely that all the gas-fired capacity will be required anyway.

So the practical outcome is that as demand reduces, generators are taken
off-line in reverse order of marginal cost.

Sylvia.

 

[Sylvia Else]

Davo wrote:

Sylvia Else wrote:
Davo wrote:

The backup issue is a load of wank, since solar cell owners will be
drawing on the grid when demand is low, such as night time. Coal
fired generators are at their maximum efficiency under full load,
anything less is losing money.

Coal fired stations run pretty much at full power all the time anyway,
because they have the lowest marginal cost. But they're also expensive
to build, so they don't get built unless the baseload power demand
ensures that they'll be able to run all the time.

It's natural gas and other types that are brought on and off line as
demand varies.

The backup issue arises because there has to be capacity available in
the system to supply power to the owners of PV cells whenever the
latter happen not to be generating power.

Another way of seeing how this impacts on electricty costs is to
consider the effect that the existence of PV cells has on generation
investment decisions. Because the cells displace generating capacity
when the sun is shining, they reduce the proportion of the time that
generating capacity is used. This shifts investment decisions towards
plant that has a lower capital and higher operating cost. The total
cost of power from such plant is higher, and that higher cost has to
be born by the power consuming community.

Sylvia.

I only know about the West Australian grid where the base load is
determined on economics, and gas, being cheaper than coal, will be burnt
before coal. Gas gets a pretty good deal in WA due to various historical
political reasons. So when the load drops it's a battle between the coal
fired generators to see who gets dropped off. The so called "back-up
issue" isn't an issue because there's plenty of spare capacity at night
when industry is sleeping.

You can't use spare capacity from night time as backup for daytime
demand, because electrical energy cannot be economically stored. Thus
the PV owners are using daytime capacity as free backup during the day.

Sylvia.

 

[terryc]

On Wed, 25 Mar 2009 17:53:39 +1100, Sylvia Else wrote:

Now, if some of those roofs have PV installations, their output varies
with the sunshine and they are right on the spot to provide power where
and when needed, actually before it is needed.

And when the clouds close over again, the PV output drops, but the
airconditioners are still on until said coddled house mums get round to
turning them off, thus leading to a power shortfall.

Completely irrelevant to the point I made. As I said, buy then the hydro
and ICEs can have turbines spinning.

In reality, of course, the situation isn't like that. Clouds do not part
over large areas at once, and people do not react instantly. What
happens is that as the load increases the frequency tends to drop.
Generators providing frequency control (a special service for which they
get paid) then increase their output to maintain the frequency. They can
do that very rapidly because the generators are already rotating at the
correct rate. Essentially they just open the throttle to prevent the
generator from slowing down.

Correct, but you have totally ignored reality that turbines are not
rotating unless they are scheduled to be running. Local PV can cover the
spin up time.

Also, according to your often repeated mantra, there isn't any capacity
for those spinning turbines to supply the extra load.

 

[terryc]

On Wed, 25 Mar 2009 20:22:03 +1100, Sylvia Else wrote:

You can't use spare capacity from night time as backup for daytime
demand, because electrical energy cannot be economically stored. Thus
the PV owners are using daytime capacity as free backup during the day.

No, they are contributing to power generation as a time when it is in
highest demand. Your point only exist in an extremist attitude.

 

[Sylvia Else]

terryc wrote:

On Wed, 25 Mar 2009 17:53:39 +1100, Sylvia Else wrote:


Now, if some of those roofs have PV installations, their output varies
with the sunshine and they are right on the spot to provide power where
and when needed, actually before it is needed.
And when the clouds close over again, the PV output drops, but the
airconditioners are still on until said coddled house mums get round to
turning them off, thus leading to a power shortfall.

Completely irrelevant to the point I made. As I said, buy then the hydro
and ICEs can have turbines spinning.

Why would the hydro and ICE be running when the load is being supported
by PV, just against the unknown future moment when the clouds close again?

In reality, of course, the situation isn't like that. Clouds do not part
over large areas at once, and people do not react instantly. What
happens is that as the load increases the frequency tends to drop.
Generators providing frequency control (a special service for which they
get paid) then increase their output to maintain the frequency. They can
do that very rapidly because the generators are already rotating at the
correct rate. Essentially they just open the throttle to prevent the
generator from slowing down.

Correct, but you have totally ignored reality that turbines are not
rotating unless they are scheduled to be running. Local PV can cover the
spin up time.

They're rotating if they've been scheduled to provide frequency support.
As I said, they get paid for that. That is, in addition to being paid
for the power they actually generate, they get paid for being there to
absorb fluctuations in load.

Also, according to your often repeated mantra, there isn't any capacity
for those spinning turbines to supply the extra load.

I haven't said that. If you think I did, they you've misconstrued
something I said, or are taking it out of context.

Sylvia.

 

[Mr.T]

"terryc" <newssevenspam-spam@woa.com.au> wrote in message
news:49ca144c$0$26373$c30e37c6@pit-reader.telstra.net...

On Wed, 25 Mar 2009 17:53:39 +1100, Sylvia Else wrote:
Correct, but you have totally ignored reality that turbines are not
rotating unless they are scheduled to be running. Local PV can cover the
spin up time.

Correction, *any* PV, wind, tidal power etc, can cover the spin up time,
(given suitable weather conditions only) and local roof top units are simply
the most expensive to install and maintain per kWHr, thus the most
uneconomic if it wasn't for stupid government handouts of other taxpayers
money.

Just another insane idea brought to you by Howard and Costello.

MrT.

 

[Eeyore]

Sylvia Else wrote:

terryc wrote:
Any recommendations?

Yes. Don't do it. It's a huge waste of money.

Spot on. In fact it's probably 'anti-green' too. PV solar is best suited
for for off-grid applications.

Graham

 

[Eeyore]

Sylvia Else wrote:

David L. Jones wrote:
"Sylvia Else" <sylvia@not.at.this.address> wrote in message
terryc wrote:

Any recommendations?
Yes. Don't do it. It's a huge waste of money.

Not to someone who wants it.
I'm sure Terry is aware of the cost/payback implications. There are many
reasons why people get PV installations.
No different to anything else really.

It doesn't just cost him money. It costs me money. He'll use the PV
cells to reduce his power demand when then sun is shining, and use grid
supplied electricity when it's not. This reduces the overall utilisation
of the grid and the generators attached to it, which pushes up the cost
of the electricity that it delivers. As a consumer of that electricity,
I have to pay more as a result.

Not to mention that any subsidies or 'incentives' put up the tax burden which
you also have to pay.

Until PV solar power can pay its way on a level playing field, any use of it (
beyond off-grid applications ) is simply playing politics.

Graham

 

[Eeyore]

"David L. Jones" wrote:

"Sylvia Else" <sylvia@not.at.this.address> wrote
David L. Jones wrote:
"Sylvia Else" <sylvia@not.at.this.address> wrote
terryc wrote:
Any recommendations?
Yes. Don't do it. It's a huge waste of money.

Not to someone who wants it.
I'm sure Terry is aware of the cost/payback implications. There are many
reasons why people get PV installations.
No different to anything else really.

It doesn't just cost him money. It costs me money. He'll use the PV cells
to reduce his power demand when then sun is shining, and use grid supplied
electricity when it's not. This reduces the overall utilisation of the
grid and the generators attached to it, which pushes up the cost of the
electricity that it delivers. As a consumer of that electricity, I have to
pay more as a result.

That's a very narrow minded view indeed.

Do you realise it may also help you?
You complained the other week that you needed a generator because of the
"parlous" state of the power system in Australia (and in Sydney where you
live). By Terry installing a solar system that might just help make the
power system less "parlous", and it might even SAVE you money by you not
having to buy that back up generator after all. You should be thanking him
for installing one.

Have you any idea how LITTLE electricity they provide ? Modern diesel and gas
turbine generation is very efficient for example in comparison. GE has a gas
turbine electric generator that's 60% efficient IIRC.

Graham

 

[Eeyore]

Sylvia Else wrote:

terryc wrote:

Now, if some of those roofs have PV installations, their output varies
with the sunshine and they are right on the spot to provide power where
and when needed, actually before it is needed.

And when the clouds close over again, the PV output drops, but the
airconditioners are still on until said coddled house mums get round to
turning them off, thus leading to a power shortfall.

You'll need a damn big PV installation to run air conditioning of any amount.
Maybe 20 m3

Graham

 

[Eeyore]

terryc wrote:

Sylvia Else wrote:

You can't use spare capacity from night time as backup for daytime
demand, because electrical energy cannot be economically stored. Thus
the PV owners are using daytime capacity as free backup during the day.

No, they are contributing to power generation as a time when it is in
highest demand. Your point only exist in an extremist attitude.

In some climates this MAY be true but PV solar is no panacea for all ills. It
onlt makes sense in certain situations and always does so at a HIGH cost.

Graham

 

[Eeyore]

"Mr.T" wrote:

"terryc" <newssevenspam-spam@woa.com.au> wrote in message
On Wed, 25 Mar 2009 17:53:39 +1100, Sylvia Else wrote:

Correct, but you have totally ignored reality that turbines are not
rotating unless they are scheduled to be running. Local PV can cover the
spin up time.

Correction, *any* PV, wind, tidal power etc, can cover the spin up time,
(given suitable weather conditions only) and local roof top units are simply
the most expensive to install and maintain per kWHr, thus the most
uneconomic if it wasn't for stupid government handouts of other taxpayers
money.

Correct. It's sad that PV solar panel power is so badly misrepresented. It has
its place but not as a grid source.

Just another insane idea brought to you by Howard and Costello.

Uhuh.

Graham

 

[terryc]

On Wed, 25 Mar 2009 01:09:07 +1100, Sylvia Else wrote:

- if you
can find an economic way of doing it. However, even running the
numbers on the back of an envelope will quickly show that it's not
just uneconomic - it's hugely uneconomic.

Care to share them?

I lost the envelope. But calculate the cost of the batteries you'd need
to support your day-time load. Then calculate the amount the interest
you'd earn on the money if you didn't buy batteries. Then calculate the
diffence in cost of the electricity you achieve through changing the
times you draw power from the grid.

Finally, take into account the very limited life of batteries.

The numbers show that it's a no-brainer.

Which is why the power generation industry isn't doing it already.

Power industry isn't doing it because their size in batteries can not be
purchased at the local garage.

Okay, taking my fileserver, which requires 96 watts max and my LG995E CRT
monitor which requires 72 watts max, that means 168 watts I need out of
the battery bank, or 14 amps @ 12Volt.

So, to cover 7am to 10pm, I need to store 15x14 = 210 amp hours. In lead
acid, this means 420amps hours.

Practically, that equates to 5x100AmpHr batteriess hour at $200 (old
price), or $1,000. 10 year life span means costs 28c per day in
depreciation. Loan costs is 6% atm or 20c per day.

Electricity savings are 15(0.1575-0.0554) =$1.53c. Net savings are $1.07c
per day. <BLINK> or $3,905.50c over ten years.

 

[Lu R]

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:000ca8b8$0$28955$c3e8da3@news.astraweb.com...

cth wrote:
Sylvia Else wrote:
David L. Jones wrote:
"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:00008d54$0$1986$c3e8da3@news.astraweb.com...
David L. Jones wrote:
"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:000f7581$0$17383$c3e8da3@news.astraweb.com...
terryc wrote:
Any recommendations?
Yes. Don't do it. It's a huge waste of money.
Not to someone who wants it.
I'm sure Terry is aware of the cost/payback implications. There are
many reasons why people get PV installations.
No different to anything else really.

Dave.
It doesn't just cost him money. It costs me money. He'll use the PV
cells to reduce his power demand when then sun is shining, and use
grid supplied electricity when it's not. This reduces the overall
utilisation of the grid and the generators attached to it, which
pushes up the cost of the electricity that it delivers. As a consumer
of that electricity, I have to pay more as a result.

That's a very narrow minded view indeed.

Do you realise it may also help you?
You complained the other week that you needed a generator because of
the "parlous" state of the power system in Australia (and in Sydney
where you live). By Terry installing a solar system that might just
help make the power system less "parlous", and it might even SAVE you
money by you not having to buy that back up generator after all. You
should be thanking him for installing one.

I think it unlikely that his installation of PV cells would impact on my
decision to install a generator. I doubt I would ever be able to
determine whether he'd actually improved the reliability of my supply.

By contrast, the impact his installation has on electricity pricing is
quite direct.

Sylvia.

Your analysis of why the cost goes up to grid consumers is a pretty long
bow to draw.

If the grid is utilised less (on a reasonable scale), then one of two
things are likely:

1. There'll be surplus power and generally anything surplus gets cheaper
or

That's a short term effect. In the longer term the generating capacity
will adjust to meet demand.


2. Less fuel is consumed by the power stations reducing their running
costs, and thus a potential saving is there to be be passed on. Whether
the pass-on occurs or not, of course is debatable. More fool us to buy
from a rip-off supplier if they don't pass on savings.

Fuel is not the only cost in the production of electricity. Capital is a
major cost. The equipment has to be there whether or not it's in use, and
the capital costs have to be shared amongst the users.

A person who installs solar cells is essentially using the grid as a free
backup, and their demand on the grid will be more variable, and less
predictable, than the demand of someone without solar cells. In a truely
transparent market, a person would have to pay a premium to be allowed to
buy power on the basis that they may not buy any, but are guaranteed to be
able to buy whatever amount they want whenever they want to.

Sylvia.

You're not thinking very green are you? Any lessened usage of coal power is
welcome if you believe in carbon offsets.

 

[Sylvia Else]

Lu R wrote:

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:000ca8b8$0$28955$c3e8da3@news.astraweb.com...
cth wrote:
Sylvia Else wrote:
David L. Jones wrote:
"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:00008d54$0$1986$c3e8da3@news.astraweb.com...
David L. Jones wrote:
"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:000f7581$0$17383$c3e8da3@news.astraweb.com...
terryc wrote:
Any recommendations?
Yes. Don't do it. It's a huge waste of money.
Not to someone who wants it.
I'm sure Terry is aware of the cost/payback implications. There are
many reasons why people get PV installations.
No different to anything else really.

Dave.
It doesn't just cost him money. It costs me money. He'll use the PV
cells to reduce his power demand when then sun is shining, and use
grid supplied electricity when it's not. This reduces the overall
utilisation of the grid and the generators attached to it, which
pushes up the cost of the electricity that it delivers. As a consumer
of that electricity, I have to pay more as a result.
That's a very narrow minded view indeed.

Do you realise it may also help you?
You complained the other week that you needed a generator because of
the "parlous" state of the power system in Australia (and in Sydney
where you live). By Terry installing a solar system that might just
help make the power system less "parlous", and it might even SAVE you
money by you not having to buy that back up generator after all. You
should be thanking him for installing one.
I think it unlikely that his installation of PV cells would impact on my
decision to install a generator. I doubt I would ever be able to
determine whether he'd actually improved the reliability of my supply.

By contrast, the impact his installation has on electricity pricing is
quite direct.

Sylvia.
Your analysis of why the cost goes up to grid consumers is a pretty long
bow to draw.

If the grid is utilised less (on a reasonable scale), then one of two
things are likely:

1. There'll be surplus power and generally anything surplus gets cheaper
or
That's a short term effect. In the longer term the generating capacity
will adjust to meet demand.

2. Less fuel is consumed by the power stations reducing their running
costs, and thus a potential saving is there to be be passed on. Whether
the pass-on occurs or not, of course is debatable. More fool us to buy
from a rip-off supplier if they don't pass on savings.
Fuel is not the only cost in the production of electricity. Capital is a
major cost. The equipment has to be there whether or not it's in use, and
the capital costs have to be shared amongst the users.

A person who installs solar cells is essentially using the grid as a free
backup, and their demand on the grid will be more variable, and less
predictable, than the demand of someone without solar cells. In a truely
transparent market, a person would have to pay a premium to be allowed to
buy power on the basis that they may not buy any, but are guaranteed to be
able to buy whatever amount they want whenever they want to.

Sylvia.

You're not thinking very green are you? Any lessened usage of coal power is
welcome if you believe in carbon offsets.

If one has decided that CO2 reduction is necessary, then it make sense
to achieve that by the cheapest possible means. Even wind power is
cheaper than solar PV, so solar PV just doesn't make the cut.

Sylvia.

 

[Mr.T]

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:0014a289$0$16139$c3e8da3@news.astraweb.com...

If one has decided that CO2 reduction is necessary, then it make sense
to achieve that by the cheapest possible means. Even wind power is
cheaper than solar PV, so solar PV just doesn't make the cut.

And large scale solar arrays are more cost effective than flea size home
roof top units in any case.
Just another case of government stupidity.
However wind, solar, tidal power etc. are complimentary IMO, since one may
be usable when the other is not.

MrT.

 

[Ross Herbert]

On Fri, 27 Mar 2009 11:50:02 +1100, Sylvia Else <sylvia@not.at.this.address>
wrote:


:
:If one has decided that CO2 reduction is necessary, then it make sense
:to achieve that by the cheapest possible means. Even wind power is
:cheaper than solar PV, so solar PV just doesn't make the cut.
:
:Sylvia.

If you have you ever approached your local council about erecting a tower with
minimum height of at least 10M to accommodate even a small wind turbine you will
find out they just won't allow these things, no matter how environmentally
greenhouse friendly they are. On the other hand they don't object to PV panels
on your roof. I also dispute your claim that wind power is cheaper. Assuming
that the govt rebate stiill applies, for a given output capacity, I think it
would be far cheaper to install PV than wind - assuming your local council will
approve the tower construction. The sun generally will shine for more hours than
a suitable wind will blow in the suburbs - unless you are high up and on the
coastline.

An even simpler way of reducing CO2 from electricity generation would be to
legislate that ALL houses must have a solar water heater.