What happens when solar power is cheaper than grid power?

[Sylvia Else]

Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

I need to be clear here what I mean by "unsubsidised". I mean that the
equipment can be bought and installed without a contribution from either
the government or the suppliers(s) of electricity. I'm also assuming
that customers will be able to net off their daytime electricity
consumption by selling their surplus solar power to the utility at the
same price as they'd buy it at that time of day.

There are arguments about whether such a framework is really
unsubsidised, but that's the definition I'm using here.

The subject is "what happens when...?"

At that point, rational consumers will install solar power systems.
Further, for those that cannot raise the capital, I would envisage
business moving in to install and lease the equipment to the consumer,
because it will be possible to let the consumer have electricity for
less than the grid price while providing a profit to the lessor.

So there should be solar panels on every domestic roof that receives
enough sunlight. The grid will only be supplying electrity during the
day when the sky is overcast. This affects the economics of the power
plant. In particular, I would anticipate a move away from combined cycle
(CCGT) natural gas generation to the less capital intensive, and less
energy efficient, generation plant.

That less efficient plant will produce more CO2 per kWh than the plant
that it replaces, but will produce less energy overall (since the solar
panels are producing some). I have to wonder how that pans out. Is the
CO2 purportedly saved by having the solar panels actually simply
tranferred to the outputs of the less efficient generators?

The cost of this less efficiently generated power is higher than that
produced by CCGT. Since that higher cost must be passed on to consumers,
it means that the unit cost of grid power during the day will go up,
thus further pushing the installation of solar panels.

Of course, that's based on unsubsidised solar panels with a simple
net-off of consumption. For some bizarre reason, governments still want
to help create the problem earlier than it would otherwise occur by
subsidising installation, and forcing retailers to pay more for solar
generated power than it's worth to the retailer.

I'm left wondering whether solar power is a mirage. Is it providing any
benefit whatsoever? Or is it a complete and utter waste of money,
regardless of whether CO2 emissions are a problem?

Sylvia.

 

[Sylvia Else]

On 6/07/2012 4:40 PM, Graham Cooper wrote:

the only drawback to solar is it takes 20-40 years to install more and
more panels,
they're on 5% of houses in 2010, 10% of houses in 2011, now 15% of
houses have panels.

Er, I think the fact that they don't produce power when the sun isn't
shining is another drawback.

the carbon electricity grid will just be a method to transfer power
from one house
to another - no power plants needed.

And when it's cloudy? What then?

Sylvia.

 

[TonyS]

On 6/07/2012 2:16 PM, Sylvia Else wrote:

Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

I need to be clear here what I mean by "unsubsidised". I mean that the
equipment can be bought and installed without a contribution from either
the government or the suppliers(s) of electricity. I'm also assuming
that customers will be able to net off their daytime electricity
consumption by selling their surplus solar power to the utility at the
same price as they'd buy it at that time of day.

There are arguments about whether such a framework is really
unsubsidised, but that's the definition I'm using here.

The subject is "what happens when...?"

At that point, rational consumers will install solar power systems.
Further, for those that cannot raise the capital, I would envisage
business moving in to install and lease the equipment to the consumer,
because it will be possible to let the consumer have electricity for
less than the grid price while providing a profit to the lessor.

So there should be solar panels on every domestic roof that receives
enough sunlight. The grid will only be supplying electrity during the
day when the sky is overcast. This affects the economics of the power
plant. In particular, I would anticipate a move away from combined cycle
(CCGT) natural gas generation to the less capital intensive, and less
energy efficient, generation plant.

That less efficient plant will produce more CO2 per kWh than the plant
that it replaces, but will produce less energy overall (since the solar
panels are producing some). I have to wonder how that pans out. Is the
CO2 purportedly saved by having the solar panels actually simply
tranferred to the outputs of the less efficient generators?

The cost of this less efficiently generated power is higher than that
produced by CCGT. Since that higher cost must be passed on to consumers,
it means that the unit cost of grid power during the day will go up,
thus further pushing the installation of solar panels.

Of course, that's based on unsubsidised solar panels with a simple
net-off of consumption. For some bizarre reason, governments still want
to help create the problem earlier than it would otherwise occur by
subsidising installation, and forcing retailers to pay more for solar
generated power than it's worth to the retailer.

I'm left wondering whether solar power is a mirage. Is it providing any
benefit whatsoever? Or is it a complete and utter waste of money,
regardless of whether CO2 emissions are a problem?

Sylvia.

Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

One has to wonder why large power plants based on solar and wind with
battery storage are not in the pipeline yet. Large renewable plants with
battery storage exist already at least in the US, Japan and China.
Example:
http://www.powermag.com/business/4410.html

Personally I'd prefer nuclear LFTR generation, at least for base load.
Shame that there is no hope though.

Tony

 

[Sylvia Else]

On 6/07/2012 5:18 PM, TonyS wrote:

On 6/07/2012 2:16 PM, Sylvia Else wrote:
Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

I need to be clear here what I mean by "unsubsidised". I mean that the
equipment can be bought and installed without a contribution from either
the government or the suppliers(s) of electricity. I'm also assuming
that customers will be able to net off their daytime electricity
consumption by selling their surplus solar power to the utility at the
same price as they'd buy it at that time of day.

There are arguments about whether such a framework is really
unsubsidised, but that's the definition I'm using here.

The subject is "what happens when...?"

At that point, rational consumers will install solar power systems.
Further, for those that cannot raise the capital, I would envisage
business moving in to install and lease the equipment to the consumer,
because it will be possible to let the consumer have electricity for
less than the grid price while providing a profit to the lessor.

So there should be solar panels on every domestic roof that receives
enough sunlight. The grid will only be supplying electrity during the
day when the sky is overcast. This affects the economics of the power
plant. In particular, I would anticipate a move away from combined cycle
(CCGT) natural gas generation to the less capital intensive, and less
energy efficient, generation plant.

That less efficient plant will produce more CO2 per kWh than the plant
that it replaces, but will produce less energy overall (since the solar
panels are producing some). I have to wonder how that pans out. Is the
CO2 purportedly saved by having the solar panels actually simply
tranferred to the outputs of the less efficient generators?

The cost of this less efficiently generated power is higher than that
produced by CCGT. Since that higher cost must be passed on to consumers,
it means that the unit cost of grid power during the day will go up,
thus further pushing the installation of solar panels.

Of course, that's based on unsubsidised solar panels with a simple
net-off of consumption. For some bizarre reason, governments still want
to help create the problem earlier than it would otherwise occur by
subsidising installation, and forcing retailers to pay more for solar
generated power than it's worth to the retailer.

I'm left wondering whether solar power is a mirage. Is it providing any
benefit whatsoever? Or is it a complete and utter waste of money,
regardless of whether CO2 emissions are a problem?

Sylvia.


Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Part of the issue there relates to who would pay for them. Consumers
will not install them themselves while they can use the grid as a free
energy store, which is what the net-off amounts to. Disallowing net-off
would change the economics of solar panels such that the large scale
deployment wouldn't occur until the combination of batteries and solar
panels were a cheaper source of electricity than grid power. It's going
to a long while before that's true, the electric car developments not
withstanding.

But I think it would be a brave politician who'd disallow net-off
because most consumers would never understand the rationale, and would
feel (as they're ever willing to) that they were being ripped off.

The grid side of the equation wouldn't install batteries unless forced
to, because there are cheaper ways of supplying electricity -
particularly when one considers that those other ways still have to
exist to handle the not-uncommon situation where the sun doesn't shine
for days on end.

One has to wonder why large power plants based on solar and wind with
battery storage are not in the pipeline yet. Large renewable plants with
battery storage exist already at least in the US, Japan and China.
Example:
http://www.powermag.com/business/4410.html

The answer is that they're hopelessly uneconomic, and only get built
from political motives.

Sylvia.

 

[Rheilly Phoull]

On 6/07/2012 3:40 PM, Sylvia Else wrote:

On 6/07/2012 5:18 PM, TonyS wrote:
On 6/07/2012 2:16 PM, Sylvia Else wrote:
Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

I need to be clear here what I mean by "unsubsidised". I mean that the
equipment can be bought and installed without a contribution from either
the government or the suppliers(s) of electricity. I'm also assuming
that customers will be able to net off their daytime electricity
consumption by selling their surplus solar power to the utility at the
same price as they'd buy it at that time of day.

There are arguments about whether such a framework is really
unsubsidised, but that's the definition I'm using here.

The subject is "what happens when...?"

At that point, rational consumers will install solar power systems.
Further, for those that cannot raise the capital, I would envisage
business moving in to install and lease the equipment to the consumer,
because it will be possible to let the consumer have electricity for
less than the grid price while providing a profit to the lessor.

So there should be solar panels on every domestic roof that receives
enough sunlight. The grid will only be supplying electrity during the
day when the sky is overcast. This affects the economics of the power
plant. In particular, I would anticipate a move away from combined cycle
(CCGT) natural gas generation to the less capital intensive, and less
energy efficient, generation plant.

That less efficient plant will produce more CO2 per kWh than the plant
that it replaces, but will produce less energy overall (since the solar
panels are producing some). I have to wonder how that pans out. Is the
CO2 purportedly saved by having the solar panels actually simply
tranferred to the outputs of the less efficient generators?

The cost of this less efficiently generated power is higher than that
produced by CCGT. Since that higher cost must be passed on to consumers,
it means that the unit cost of grid power during the day will go up,
thus further pushing the installation of solar panels.

Of course, that's based on unsubsidised solar panels with a simple
net-off of consumption. For some bizarre reason, governments still want
to help create the problem earlier than it would otherwise occur by
subsidising installation, and forcing retailers to pay more for solar
generated power than it's worth to the retailer.

I'm left wondering whether solar power is a mirage. Is it providing any
benefit whatsoever? Or is it a complete and utter waste of money,
regardless of whether CO2 emissions are a problem?

Sylvia.


Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Part of the issue there relates to who would pay for them. Consumers
will not install them themselves while they can use the grid as a free
energy store, which is what the net-off amounts to. Disallowing net-off
would change the economics of solar panels such that the large scale
deployment wouldn't occur until the combination of batteries and solar
panels were a cheaper source of electricity than grid power. It's going
to a long while before that's true, the electric car developments not
withstanding.

But I think it would be a brave politician who'd disallow net-off
because most consumers would never understand the rationale, and would
feel (as they're ever willing to) that they were being ripped off.

The grid side of the equation wouldn't install batteries unless forced
to, because there are cheaper ways of supplying electricity -
particularly when one considers that those other ways still have to
exist to handle the not-uncommon situation where the sun doesn't shine
for days on end.


One has to wonder why large power plants based on solar and wind with
battery storage are not in the pipeline yet. Large renewable plants with
battery storage exist already at least in the US, Japan and China.
Example:
http://www.powermag.com/business/4410.html

The answer is that they're hopelessly uneconomic, and only get built
from political motives.

Sylvia.

Apart from the solar issue, I reckon they should start a national grid
system followed by an international one. That would go a long way
towards solving the shortages in one area and taking the surplus from
the active areas. Costly I know but the longer it's left the more costly
it will become. The same goes for water.

R.P

 

[Graham Cooper]

On Jul 6, 4:16 pm, Sylvia Else <syl...@not.here.invalid> wrote:

Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

I need to be clear here what I mean by "unsubsidised". I mean that the
equipment can be bought and installed without a contribution from either
the government or the suppliers(s) of electricity. I'm also assuming
that customers will be able to net off their daytime electricity
consumption by selling their surplus solar power to the utility at the
same price as they'd buy it at that time of day.

There are arguments about whether such a framework is really
unsubsidised, but that's the definition I'm using here.

The subject is "what happens when...?"

At that point, rational consumers will install solar power systems.
Further, for those that cannot raise the capital, I would envisage
business moving in to install and lease the equipment to the consumer,
because it will be possible to let the consumer have electricity for
less than the grid price while providing a profit to the lessor.

So there should be solar panels on every domestic roof that receives
enough sunlight. The grid will only be supplying electrity during the
day when the sky is overcast. This affects the economics of the power
plant. In particular, I would anticipate a move away from combined cycle
(CCGT) natural gas generation to the less capital intensive, and less
energy efficient, generation plant.

That less efficient plant will produce more CO2 per kWh than the plant
that it replaces, but will produce less energy overall (since the solar
panels are producing some). I have to wonder how that pans out. Is the
CO2 purportedly saved by having the solar panels actually simply
tranferred to the outputs of the less efficient generators?

The cost of this less efficiently generated power is higher than that
produced by CCGT. Since that higher cost must be passed on to consumers,
it means that the unit cost of grid power during the day will go up,
thus further pushing the installation of solar panels.

Of course, that's based on unsubsidised solar panels with a simple
net-off of consumption. For some bizarre reason, governments still want
to help create the problem earlier than it would otherwise occur by
subsidising installation, and forcing retailers to pay more for solar
generated power than it's worth to the retailer.

I'm left wondering whether solar power is a mirage. Is it providing any
benefit whatsoever? Or is it a complete and utter waste of money,
regardless of whether CO2 emissions are a problem?

Sylvia.

yeh right. they'll turn off the 24 hours generators during the day
to produce more CO2 while they wait for the solar panels to stop
working
and can turn on again to make less CO2.

everyone over a means test should be paying 10X quota for grid
electricity,
if you have the means you can provide your own electricity easily

the only drawback to solar is it takes 20-40 years to install more and
more panels,
they're on 5% of houses in 2010, 10% of houses in 2011, now 15% of
houses have panels.

the carbon electricity grid will just be a method to transfer power
from one house
to another - no power plants needed.


Herc

 

[Sylvia Else]

On 6/07/2012 6:43 PM, Graham Cooper wrote:

On Jul 6, 5:40 pm, Sylvia Else <syl...@not.here.invalid> wrote:
http://www.powermag.com/business/4410.html

The answer is that they're hopelessly uneconomic, and only get built
from political motives.

Sylvia.

Wot Rot!

If you can pay your power bill 3 years in advance you can go to Solar
and never pay a bill again!

You put a sheet of cardboard on your roof and get 100W for every 1m2!

Oh no! the clouds! the clouds!

What have you got your mums head in a cryogenic freezer in the
basement?

Herc

Graham, there are two entirely different situations.

The first, which is the one you're talking about, is where the
government subsidises your solar panels, and lets you treat the grid as
a free battery, and possibly pays you more for the electricity you
generate than it's actually worth.

The other is the real world, unmodified by politicians who think you can
legislate that one chicken be counted as two, where all of the costs of
acquiring power have to be paid by someone, not just some of them.

Sylvia.

 

[TonyS]

On 6/07/2012 3:40 PM, Sylvia Else wrote:
[]

The grid side of the equation wouldn't install batteries unless forced
to, because there are cheaper ways of supplying electricity -
particularly when one considers that those other ways still have to
exist to handle the not-uncommon situation where the sun doesn't shine
for days on end.

It's the bleeding obvious

One has to wonder why large power plants based on solar and wind with
battery storage are not in the pipeline yet. Large renewable plants with
battery storage exist already at least in the US, Japan and China.
Example:
http://www.powermag.com/business/4410.html

The answer is that they're hopelessly uneconomic, and only get built
from political motives.

True. True is also that the present economy is a false one. The
environmental damage is not priced in yet. Even with the carbon tax.
We are using a technology that is almost 150 years old, because it is
cheap and convenient. Shift the goal posts and you will be amazed how
quickly new, and possibly even cheaper technologies will emerge.
Example:
http://web.mit.edu/newsoffice/2011/flow-batteries-0606.html
Sometimes we need political power to overcome the power of the capital,
to push the cart in a different direction. It's been dragging on for too
long. Would you have imagined 20 years ago that so soon we will have
1000 Gbyte hard disks in a laptop?

Tony

 

[terryc]

On 06/07/12 16:16, Sylvia Else wrote:

Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

What is the basis of that claim?
Grid power equals very large economy of scale.
Solar power equals expensive, high maintenance storage device.

 

[terryc]

On 06/07/12 17:18, TonyS wrote:

Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Way to shoot yorself in the foot. If there is one battery that would
illustrate your point, it is the basic lead acid battery as in the
standard car battery, or even derivative, aka the deep discharge lead
acid battery as used in power systems. cost of them is still a major
sticking point.

 

[terryc]

On 06/07/12 17:53, Rheilly Phoull wrote:

Apart from the solar issue, I reckon they should start a national grid
system followed by an international one. That would go a long way
towards solving the shortages in one area and taking the surplus from
the active areas. Costly I know but the longer it's left the more costly
it will become. The same goes for water.

Transmissin losses in both cases. You can shift electrical AC power
around and minimises the losses by bumping the transmission voltage. SFA
you can do with water, except pay monstrous power bills for pumping.

 

[Graham Cooper]

On Jul 6, 5:40 pm, Sylvia Else <syl...@not.here.invalid> wrote:

http://www.powermag.com/business/4410.html

The answer is that they're hopelessly uneconomic, and only get built
from political motives.

Sylvia.

Wot Rot!

If you can pay your power bill 3 years in advance you can go to Solar
and never pay a bill again!

You put a sheet of cardboard on your roof and get 100W for every 1m2!

Oh no! the clouds! the clouds!

What have you got your mums head in a cryogenic freezer in the
basement?

Herc

 

[Graham Cooper]

On Jul 6, 6:52 pm, Sylvia Else <syl...@not.here.invalid> wrote:

On 6/07/2012 6:43 PM, Graham Cooper wrote:









On Jul 6, 5:40 pm, Sylvia Else <syl...@not.here.invalid> wrote:
http://www.powermag.com/business/4410.html

The answer is that they're hopelessly uneconomic, and only get built
from political motives.

Sylvia.

Wot Rot!

If you can pay your power bill 3 years in advance you can go to Solar
and never pay a bill again!

You put a sheet of cardboard on your roof and get 100W for every 1m2!

Oh no!  the clouds!  the clouds!

What have you got your mums head in a cryogenic freezer in the
basement?

Herc

Graham, there are two entirely different situations.

The first, which is the one you're talking about, is where the
government subsidises your solar panels, and lets you treat the grid as
a free battery, and possibly pays you more for the electricity you
generate than it's actually worth.

The other is the real world, unmodified by politicians who think you can
legislate that one chicken be counted as two, where all of the costs of
acquiring power have to be paid by someone, not just some of them.

Sylvia.

http://jaycar.com.au/productView.asp?ID=SB1695&form=CAT2&SUBCATID=997#12
$305
12V 100AH DEEP CYCLE GEL BATTERY
Deep-cycle gel performance for solar installations


http://www.jaycar.com.au/productView.asp?ID=ZM9088
$659
200W Powertech Monocrystalline Solar Panel


http://www.jaycar.com.au/productView.asp?ID=MI5262
$1400 (from $350 for 1500W)
2000W Sine Wave Inverter Charger
Combining the functions of a pure sine wave inverter, battery charger
and automatic transfer switch in one unit


BACKUP!
Hardly a noise if you dig a small ditch.
http://www.jaycar.com.au/productView.asp?ID=MG4502
$899
2kW Sine Wave Inverter Generator


*******

Demo setup in hot city..

900W airconditioner.

5 hours direct sunlight run during day
+ 5 hour run at night
= 1800W Solar Panels

200W = $650
2000W = $6500

5 hours charge at 1000W
/10V = 100AMP

5 100AH batteries = $3000

That's an AIRCONDITIONER 10 hours a day.

If you can get away with fans or evap. cooling you could power 5
houses with that setup!

If you only power the aircon during peak sun, only 1/3 that price.

I'm setting up a $3000 - $4000 setup this month just to run a 400W
halogen heater, microwave etc.

I just used my printer for an hour with a $50 inverter and the $500
panels and batteries setup I have now.

Herc

 

[Graham Cooper]

On Jul 6, 7:19 pm, terryc <newsninespam-s...@woa.com.au> wrote:

On 06/07/12 17:18, TonyS wrote:

Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Way to shoot yorself in the foot. If there is one battery that would
illustrate your point, it is the basic lead acid battery as in the
standard car battery, or even derivative, aka the deep discharge lead
acid battery as used in power systems. cost of them is still a major
sticking point.

It's the REPLACEMENT COST of the batteries.

http://jaycar.com.au/productView.asp?ID=SB1695&form=CAT2&SUBCATID=997#12

12V 100Ah Deep Cycle Gel Battery
$305

This will deliver 1200W for 1 hour.

But if you fully charge and fully discharge every day..

3 month = 91%
6 months = 82%
12 months = 64%

so it loses 9% every 90 days.

But if you don't run AIRCON and ELECTRIC OVENS

you can effectively trickle charge them.

i.e. have way more batteries than panels.

you can supply a good SURGE POWER - i.e. microwaves, pressure
cleaners..
and keep the batteries charged for 1-2 weeks of cloud cover,
but your total power usage must be kept down.

then you get triple benefit
by batteries only charging / discharging 10% capacity each day

1 long battery life in decades
2 batteries always topped up over 2 weeks cloud cover
3 high surge power when needed

Herc

 

[Sylvia Else]

On 6/07/2012 7:10 PM, Graham Cooper wrote:

Hardly a noise if you dig a small ditch.
http://www.jaycar.com.au/productView.asp?ID=MG4502
$899
2kW Sine Wave Inverter Generator

And how much will you end up running it? Quite a lot in practice, and it
requires an oil change very 20 hours. It's not designed to be used
semi-continuously. The petrol costs will be significant.

Sylvia.

 

[Sylvia Else]

On 6/07/2012 7:49 PM, Graham Cooper wrote:

On Jul 6, 7:19 pm, terryc <newsninespam-s...@woa.com.au> wrote:
On 06/07/12 17:18, TonyS wrote:

Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Way to shoot yorself in the foot. If there is one battery that would
illustrate your point, it is the basic lead acid battery as in the
standard car battery, or even derivative, aka the deep discharge lead
acid battery as used in power systems. cost of them is still a major
sticking point.


It's the REPLACEMENT COST of the batteries.

http://jaycar.com.au/productView.asp?ID=SB1695&form=CAT2&SUBCATID=997#12

12V 100Ah Deep Cycle Gel Battery
$305

This will deliver 1200W for 1 hour.

But if you fully charge and fully discharge every day..

3 month = 91%
6 months = 82%
12 months = 64%

so it loses 9% every 90 days.

But if you don't run AIRCON and ELECTRIC OVENS

you can effectively trickle charge them.

i.e. have way more batteries than panels.

you can supply a good SURGE POWER - i.e. microwaves, pressure
cleaners..
and keep the batteries charged for 1-2 weeks of cloud cover,
but your total power usage must be kept down.

then you get triple benefit
by batteries only charging / discharging 10% capacity each day

1 long battery life in decades
2 batteries always topped up over 2 weeks cloud cover
3 high surge power when needed

Herc

The cost of capital gets you then. All that money tied up in batteries
that could be earning interest in a bank account or and capital gains
and dividends invested in shares.

Sylvial

 

[Sylvia Else]

On 6/07/2012 7:17 PM, terryc wrote:

On 06/07/12 16:16, Sylvia Else wrote:
Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

What is the basis of that claim?
Grid power equals very large economy of scale.
Solar power equals expensive, high maintenance storage device.

I haven't looked at the details. Prices of panels have been dropping,
and the price of grid power (particularly in NSW) have been rising.
There's going to be a crossover point.

I've assumed in the discussion that no storage devices are involved. The
point of the posting was not to argue that solar is cheap, or cost
effective, but just to look at what will happen at some point in the
future given the way things have been going, and to raise a question
about whether solar panels are actually achieving anything other than to
line the pockets of some manufacturers.

Sylvia.

 

[terryc]

On 06/07/12 19:49, Graham Cooper wrote:

On Jul 6, 7:19 pm, terryc<newsninespam-s...@woa.com.au> wrote:
On 06/07/12 17:18, TonyS wrote:

Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Way to shoot yorself in the foot. If there is one battery that would
illustrate your point, it is the basic lead acid battery as in the
standard car battery, or even derivative, aka the deep discharge lead
acid battery as used in power systems. cost of them is still a major
sticking point.


It's the REPLACEMENT COST of the batteries.
Why are they magically cheaper when you replace them?

http://jaycar.com.au/productView.asp?ID=SB1695&form=CAT2&SUBCATID=997#12

12V 100Ah Deep Cycle Gel Battery
$305
Very expensive.

This will deliver 1200W for 1 hour.

Definitely not unless you want to explode the battery. That rating is at
best 60watts for five hours. Any more or longer and the life cycles head
south.

But if you fully charge and fully discharge every day..
Then you are definitely fscking it.

 

[Peter]

Sylvia Else <sylvia@not.here.invalid> wrote:

On 6/07/2012 7:17 PM, terryc wrote:
On 06/07/12 16:16, Sylvia Else wrote:
Opinions on this vary, but it appears that sometime in the next ten
years, domestic solar power will have an unsubsidised cost that is below
the daytime domestic grid tarrif.

What is the basis of that claim?
Grid power equals very large economy of scale.
Solar power equals expensive, high maintenance storage device.

I haven't looked at the details. Prices of panels have been dropping, and
the price of grid power (particularly in NSW) have been rising. There's
going to be a crossover point.

I've assumed in the discussion that no storage devices are involved. The
point of the posting was not to argue that solar is cheap, or cost
effective, but just to look at what will happen at some point in the
future given the way things have been going, and to raise a question
about whether solar panels are actually achieving anything other than to
line the pockets of some manufacturers.

Sylvia.

Why do they install a roof just to cover it with solar panels?
I would imagine solar panel roofing material (tiles/paint) could save in
building costs and alter the math.

--

 

[Graham Cooper]

On Jul 6, 11:42 pm, terryc <newsninespam-s...@woa.com.au> wrote:

On 06/07/12 19:49, Graham Cooper wrote:







On Jul 6, 7:19 pm, terryc<newsninespam-s...@woa.com.au>  wrote:
On 06/07/12 17:18, TonyS wrote:

Your scenario is based on the assumption that electricity can not be
stored economically. Having batteries of such a scale will soon be more
common though, especially with ever more electric cars, the numbers will
make them cheaper. Lithium batteries are increasing in efficiency by
about 7%/year, and with panels getting ever cheaper even the low
efficiency NiFe type could be considered.

Way to shoot yorself in the foot. If there is one battery that would
illustrate your point, it is the basic lead acid battery as in the
standard car battery, or even derivative, aka the deep discharge lead
acid battery as used in power systems. cost of them is still a major
sticking point.

It's the REPLACEMENT COST of the batteries.

Why are they magically cheaper when you replace them?





http://jaycar.com.au/productView.asp?ID=SB1695&form=CAT2&SUBCATID=997#12

12V 100Ah Deep Cycle Gel Battery
$305
Very expensive.

This will deliver 1200W for 1 hour.

Definitely not unless you want to explode the battery. That rating is at
best 60watts for five hours. Any more or longer and the life cycles head
south.

that's only 5AMP! wouldn't even get warm!

But if you fully charge and fully discharge every day..

Then you are definitely fscking it.

you still have 64% capacity after 1 year, that's with full 365 charge/
discharge cycles.

This isn't my suggested usage, quite the opposite.

check the link there is a data pdf file which I quoted part of.

including the 1 hour discharge capacity.

Herc