What happens when solar power is cheaper than grid power?

[Sylvia Else]

Of course we could all start using these instead:

http://www.empasys.net/

No fuel or other enery inputs. Lasts forever. "Ambient energy conversion
with quantum coherence technology."

Sounds almost too good to be true.

Sylvia.

 

[Sylvia Else]

You just tap the thermal energy in the Ocean.

1% energy fee to separate ocean temp down to 5 degrees.

Cheap solar heaters to get 60 degree lakes.

Mix 60 degree and 5 degree sources and you get 55/275 efficiency
stirling engine or peltier generators.

Herc

You can get energy out of the ocean, but it takes so much infrastructure
to get so little energy that it simply makes no economic sense. Which is
why no one is using it as a serious energy supply.

Indeed, why go to the ocean. Connect up a bunch of microphones, and just
collect energy from the outside ambient noise.

Economic. That's the word you need to remember. It's not sufficient for
something to be physically possible. It has to be economic before it
will be used in the mainstream.

Sylvia.

 

[terryc]

No you idiot! that IS the rating given. full discharge over 24 hours
X 365

actually its probably 12hrs up and 12hrs down.

Which automatically reduces the effective capacity.
Hint, go read the fine print. Advertised capacity is rated over 20 hours.

Hint, look at tables for solar insolation/isolation. The sun doesn't
shine effectively for 12 hours. In fact, search for effective sun hours.

 

[Sylvia Else]

if you are worrying about "emissions" I guess you should also worry about whether or not the solar panels provide a slippery surface that could be a safety issue for when Santa lands his sleigh on the roof at Christmas. This is a far more real concern.

I'm not, particularly, but clearly some people are. It would be annoying
in the extreme if I'm having pay more for electricity because people are
implementing alleged CO2 reducing technologies that don't actually work.

Sylvia

 

[Sylvia Else]

SOLAR GETS POPULAR
-> less energy required
-> cheaper power plants
-> no economy of scale
-> less efficient
-> burn more fuel
-> more pollution

OK, at what point does this actually produce more CO2?

Where is your DATA comparing 2 different sized power stations.

It's not that they're different sized in terms of power output, it's
that they are constructed differently.

The basic principle is this:

Capital investment incurs a cost - it's the money that could have been
earnt using the capital if it hadn't been invested in the particular
way. That cost continues day by day whether or not the generation plant
is running.

Running a generation plant incurs a cost - it's the money used to
provide it with fuel (and maintenance and other minor elements, but
mainly fuel). But unlike the capital cost, the running cost is only
incurred when the plant is running.

So for a given power capacity, there's a compromise to be made between
the capital cost and the running cost. The more capital you spend, the
more efficient you can make the plant, and the less fuel it will
consume. But the less the plant runs, the less you gain from the extra
capital. Beyond a certain point, additional capital doesn't pay for
itself in terms of reduced fuel consumption. Where that point lies
depends on the percentage utilisation.

Solar panels on roofs will reduce the time that other generation plant
is running. Essentially, the plant that would be running during the day
in the absence of solar panels will only be running when the sun isn't
shining. When it comes time to replace or build that plant, the decision
will be made that it's not sensible to spend so much capital on making
it efficient. So, for a given energy output, it will consume more fuel,
and therefore produce more CO2.

That's a qualititive analysis. I don't have the data for a quantitive one.

What ratio of size difference in power station will there be until
they do a bait-and-switch and swap to using those unearthly
inefficient smaller power stations that churn out X times CO2 due to
inefficiency of scale?

It's not an inefficiency of scale. See above.

You reduce power requirements by 50%
and CO2 emmission goes up?

Where did you think up such a bunch of tripe?

You thought it up. I didn't say it.

Sylvia.

 

[F Murtz]

You can get energy out of the ocean, but it takes so much infrastructure
to get so little energy that it simply makes no economic sense. Which is
why no one is using it as a serious energy supply.

Indeed, why go to the ocean. Connect up a bunch of microphones, and just
collect energy from the outside ambient noise.

Economic. That's the word you need to remember. It's not sufficient for
something to be physically possible. It has to be economic before it
will be used in the mainstream.

Sylvia.

all of this discussion is about research using known technologies or
derivations, what is needed and will happen someday, is some genius
thinking completely out of the square that comes up with something
totally different. the main problem with this is that it has the
potential to completely alter economies and send the world in a spin, so
the genius had better be careful.

 

[terryc]

there is not ONE person on the planet who speaks sincerely and
honestly addresses the actual intent of questions.

Well, perhaps the intent isn't being communicated freely.

fucking monkeys
boonoobo?


BOOHOOO Free Energy!

No, t isn't fscking but scratching the metal tubes in differen ways with
different signs and I' fzzt how t gives you free energy, but they clam
it does.

 

[Clocky]

or wind up springs!

Looks like you have drifted off into fantasyland again...

 

[Phil Allison]

"Sylvia Else"

It would be annoying in the extreme if I'm having pay more for electricity
because people are implementing alleged CO2 reducing technologies that
don't actually work.

** Nooooooo .....

Now who ever would think a terrible thought like that ??




..... Phil

 

[terryc]

I'm not, particularly, but clearly some people are. It would be annoying
in the extreme if I'm having pay more for electricity because people are
implementing alleged CO2 reducing technologies that don't actually work.

Do you mean like carbon capture and sequestration?

 

[Yaputya]

"Sylvia Else"


** Nooooooo .....

Now who ever would think a terrible thought like that ??




.... Phil

Wow!!!
That's the closest thing to a love-letter to Sylvia that Phil has ever posted!!!!

 

[swanny]

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.

It's not really very efficient, even if they were available. Unless all
of your roof is facing North and unobstructed by adjacent buildings of
shading from trees. This is very rare. I looked at this option During
the design of my current house and decided it was not cost effective,
despite half the roof facing North. A low thermal inertia roof skin with
hot water and PV panels mounted at the most effective places is a better
option.

 

[swanny]

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.

It would be interesting to know what the cost per kWh would be over the
lifetime of the average PV system, amortising capital cost and eventual
disposal costs into the price. Then compare that to the average grid
feed price per kWh.

 

[terryc]

It would be interesting to know what the cost per kWh would be over the
lifetime of the average PV system, amortising capital cost and eventual
disposal costs into the price. Then compare that to the average grid
feed price per kWh.

That is what we are trying to educate Herc about.

 

[Sylvia Else]

Do you mean like carbon capture and sequestration?

Well that's a bit different. If it can be made to work (economically!)
and provided the stuff stays where it's been put, and doesn't escape
causing mass fatalites, then it will reduce the CO2 output to the
atmosphere.

That's not the same as a technology that looks as if it should work, but
doesn't, when all the ramifications of using it are taken into account.

Sylvia.

 

[Trevor Wilson]

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.

**Thinking outside the box over the weekend. Let's say you plonk a dirty
great PV array on your roof in a year or two. Then you buy yourself a
Holden Volt. During the day, you plug your Volt into the power supplied
by the PV array. Given the fact that you are (in theory) a typical
Australian driver, your driving is limited to around 40km/day. That
suggests you will never use anything but renewable energy to power your
car. That would result in a useful reduction in CO2 emissions. If
several million car owners did the same thing, the results would be
significant.

 

[Trevor Wilson]

you can put your 2 electrodes into rainwater and fill your own
hydrogen tanks.

very efficient too!

**No, it is not. Around 30% efficient, in fact.

now THAT is how you store the solar power station energy for 18 hours
each night and run hydrogen plants overnight.

no batteries - 100% solar. cloud proof.

**Yes, it is, but there are better ways.

 

[Trevor Wilson]

Sylvia gave a figure of 90% last year or around there.

**The 90% figure may be the theoretical figure. The actual figure is far
lower.

The car battery is going to cost you more than petrol

**Duh. Fortunately, the battery can be recharged many times, with the
'free' energy provided by PV cells.

Nope! Not unless you use thermal energy and masses and masses of
pissy thermal generators.

Hydrogen is how it's all done.

SOLAR >> ELECTRICITY >> HYDROGEN >> GENERATOR >> ELECTRICITY
V V
V V
ELECTRICITY HYDROGEN >> CARS



Herc

**Not yet. The conversion efficiency is (presently) far too low.

 

[Clocky]

**Thinking outside the box over the weekend. Let's say you plonk a
dirty great PV array on your roof in a year or two. Then you buy
yourself a Holden Volt. During the day, you plug your Volt into the
power supplied by the PV array. Given the fact that you are (in
theory) a typical Australian driver, your driving is limited to
around 40km/day. That suggests you will never use anything but
renewable energy to power your car. That would result in a useful
reduction in CO2 emissions. If several million car owners did the
same thing, the results would be significant.

Not really, remember that producing a new Volt and the solar array required
to power it would produce more CO2 than driving a $500 20 year old Commodore
(for instance) for the life of the Volt and the solar array.

 

[Clocky]

Sylvia gave a figure of 90% last year or around there.

The car battery is going to cost you more than petrol





Nope! Not unless you use thermal energy and masses and masses of
pissy thermal generators.

Hydrogen is how it's all done.

SOLAR >> ELECTRICITY >> HYDROGEN >> GENERATOR >> ELECTRICITY
V V
V V
ELECTRICITY HYDROGEN >> CARS

You obviously don't know how much power and how slow the process is to get
the hydrogen using electricity.

Impractical, inefficient and not even remotely cost effective - or
environmentally friendly.

There is no free lunch.