Rooftop Pv installers in Sydney area

[Sylvia Else]

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]

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]

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]

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]

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?

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]

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]

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]

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]

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]

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]

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]

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

 

[Lu R]

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


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]

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]

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]

:
: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.

 

[Sylvia Else]

:
: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.

Small domestic wind turbines make no sense anyway. If you're going to
spend money on a turbine, you want it big, you want it high, and you
want it in a place that tends to get a lot of wind.

I recently went through the numbers on a solar water heater when my
electric heater was clearly on its last legs. Even with the government
rebates, the result was marginal, meaning that the true financial cost
was significantly higher than for an purely electric storage heater.

The best that can be said for solar hot water heaters is they're more
economic than other forms of solar power (and perhaps than wind power).
They *might* be the cheapest way to heat water when all the external
costs (CO2, etc) are included, if nuclear power is not acceptable.

Sylvia.

 

[Mr.T]

Small domestic wind turbines make no sense anyway.

In the same way as small domestic PV panels don't.

MrT.

 

[Mauried]

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.

You need to do some serious research into lead acid batteries.
The type of application you are looking at needs deep cycle
batteries,not car batteries.
A 12 V 200AH deep cycle battery will cost you anywhere from $800 to
$1000.

 

[terryc]

You need to do some serious research into lead acid batteries. The type
of application you are looking at needs deep cycle batteries,not car
batteries.
Yep

A 12 V 200AH deep cycle battery will cost you anywhere from $800 to
$1000.

where are you buying those from?
Surely not Battery World?
BTw,I probably would not buy ones that big, but 2 x 6V200AmpHr