Posted by Tim Jackson on April 25, 2009, 9:22 pm
Lord Gow333, Dirk Benedict's newest fan! wrote:
>
> My point wasn't a mass scale solution for Global Warming, but rather
> that any individual trying to cut Global Warming by installing solar
> panels would be better off laying down an equal amount of mirrors
> instead, as in their current state solar panels directly generate heat
> in what is likely a greater amount than they can counteract.
>
> LG
We are not trying to reduce global warming by reducing the absorbed
solar radiation. We are trying to do it by reducing the emission of
greenhouse gases which otherwise reduce heat loss heat over a long
period of time.
The amount of energy generated while producing a kilo of CO2 by burning
organic fuels is tiny compared to the total energy which that kilo of
CO2 keeps in by reducing the earth's infra-red radiation, over the time
for which it stays in the atmosphere.
So what you need to compare is the additional absorption of insolation
by the panel over the mirror, versus the energy loss reduction produced
by the equivalent fossil fuel power source, over the lifetime of the
emitted CO2. On that basis you will find the solar panels win hands
down. It is only when you take into account the construction,
installation and maintenance costs that they start to lose.
Tim
Posted by Lord Gow333, Dirk Benedict's n on April 27, 2009, 1:38 am
> Lord Gow333, Dirk Benedict's newest fan! wrote:
>>
>> My point wasn't a mass scale solution for Global Warming, but rather that
>> any individual trying to cut Global Warming by installing solar panels
>> would be better off laying down an equal amount of mirrors instead, as in
>> their current state solar panels directly generate heat in what is likely
>> a greater amount than they can counteract.
>>
>> LG
> We are not trying to reduce global warming by reducing the absorbed solar
> radiation. We are trying to do it by reducing the emission of greenhouse
> gases which otherwise reduce heat loss heat over a long period of time.
> The amount of energy generated while producing a kilo of CO2 by burning
> organic fuels is tiny compared to the total energy which that kilo of CO2
> keeps in by reducing the earth's infra-red radiation, over the time for
> which it stays in the atmosphere.
> So what you need to compare is the additional absorption of insolation by
> the panel over the mirror, versus the energy loss reduction produced by
> the equivalent fossil fuel power source, over the lifetime of the emitted
> CO2. On that basis you will find the solar panels win hands down. It is
> only when you take into account the construction, installation and
> maintenance costs that they start to lose.
Alrighty then. That's what I was wondering. Of course this is all based on
the whole melting ice caps, dead polar bears, Algore greenhouse gas
theory...
LG
--
"Keep it simple. If it takes a genius to understand it, it will never work."
- Clarence Leonard "Kelly" Johnson
Posted by Tim Jackson on April 27, 2009, 7:56 am
Lord Gow333, Dirk Benedict's newest fan! wrote:
>
>> We are not trying to reduce global warming by reducing the absorbed
>> solar radiation. We are trying to do it by reducing the emission of
>> greenhouse gases which otherwise reduce heat loss heat over a long
>> period of time.
>>
>> The amount of energy generated while producing a kilo of CO2 by
>> burning organic fuels is tiny compared to the total energy which that
>> kilo of CO2 keeps in by reducing the earth's infra-red radiation, over
>> the time for which it stays in the atmosphere.
> Alrighty then. That's what I was wondering. Of course this is all based
> on the whole melting ice caps, dead polar bears, Algore greenhouse gas
> theory...
>
> LG
Not really, it's all based on physics. The physical properties of CO2
are well known. It's lifetime in the atmosphere is well known. Its
atmospheric concentration is uncontroversial. There is ample evidence
of a general warming of the planet, such as the progressive changes in
the ranges of many plants and animals, including humans; acidification
of the oceans; as well as the progressive collapse of the ice caps and
the unseemly scrabble to grab the oil reserves becoming exposed as the
ice melts (how stupid can you get?).
Whether or not this is caused by human action is irrelevant (although
the evidence does seem overwhelming that it is), the question is not who
caused it but who can stop it. And Al Gore did not invent the theory,
he only jumped on an existing bandwagon and publicised it.
When this thing first started to revive after the Club of Rome report
got rubbished, I saw a few articles mentioning odd bits of evidence of
current CO2 levels being way above historical levels, statistical
warming trends, etc, and a little speculation that this might promote a
significant change in the climate and in sea levels. As each new piece
of evidence was reported the outline of the elephant started to become
apparent. My gut feeling was that this thing is going to be much bigger
than was being reported because no reputable scientist is going to risk
their funding and career by disturbing the status quo and antagonising
established power bases, and because everyone is concentrating on their
particular speciality - ice cores, coral bleaching, sea level history,
whatever and studiously avoiding getting involved in the inevitably
controversial big picture. It's how science works.
So far my gut feeling has been borne out. Almost every new projection,
every improvement in the climate models, every new piece of evidence,
has made things look worse - projections of the rate of sea-level rise
for example have given progressively shorter timescales (and almost
reached the asymptote I predicted five years ago, but I admit that's
mostly luck).
The concept of a global conspiracy to distort the scientific findings in
a direction unfavourable to most global seats of power seems rather hard
to swallow. I do admit that my own views are informed by being a
regular reader of New Scientist, and if its reporting is heavily biased
then that might influence my opinion. Certainly its editorial view is
now that climate change is a big problem, but I am sure that is simple
reflecting the view of a majority of scientists.
Personally I have no axe to grind, I made money out of the North Sea oil
boom but used it to set up my own business outside of that industry. My
home is 800' above sea level in a free-draining location, and in a area
where global warming is as likely to lead to local cooling as warming.
My main interest is to prepare my children to survive whatever the
future might throw at them.
Tim Jackson
Posted by Lord Gow333, Dirk Benedict's n on April 27, 2009, 3:56 pm
> Lord Gow333, Dirk Benedict's newest fan! wrote:
>>
>>> We are not trying to reduce global warming by reducing the absorbed
>>> solar radiation. We are trying to do it by reducing the emission of
>>> greenhouse gases which otherwise reduce heat loss heat over a long
>>> period of time.
>>>
>>> The amount of energy generated while producing a kilo of CO2 by burning
>>> organic fuels is tiny compared to the total energy which that kilo of
>>> CO2 keeps in by reducing the earth's infra-red radiation, over the time
>>> for which it stays in the atmosphere.
>> Alrighty then. That's what I was wondering. Of course this is all based
>> on the whole melting ice caps, dead polar bears, Algore greenhouse gas
>> theory...
>>
>> LG
> Not really, it's all based on physics. The physical properties of CO2 are
> well known. It's lifetime in the atmosphere is well known. Its
> atmospheric concentration is uncontroversial. There is ample evidence of
> a general warming of the planet, such as the progressive changes in the
> ranges of many plants and animals, including humans; acidification of the
> oceans; as well as the progressive collapse of the ice caps and the
> unseemly scrabble to grab the oil reserves becoming exposed as the ice
> melts (how stupid can you get?).
> Whether or not this is caused by human action is irrelevant
Lost me right abouuuuuuuut...
>(although the evidence does seem overwhelming that it is),
...here.
>the question is not who caused it but who can stop it. And Al Gore did not
>invent the theory, he only jumped on an existing bandwagon and publicised
>it.
No, Algore jumped on the existing private jet and burned up God knows how
much fossil fuel flying around like a nitwit preaching to everybody how we
have to conserve.
The fact that he's invested in a company that deals in "carbon offsets" I'm
certain has nothing to do with it either...
LG
--
These "conserve" folks remind me of the miserly lady that saves plastic
spoons and Wendy's cups when she has $0 million in the bank. - Trijcomm
Posted by Eeyore on April 25, 2009, 8:41 pm
"Lord Gow333, Dirk Benedict's newest fan!" wrote:
> > Frank wrote:
> >
> >> Efficient or not solar and wind devices are front end loaded with fossil
> >> fuel consumption and their carbon foot print would not become net level
> >> until late in their life cycles. At this point, I'd say the talk show
> >> hosts are correct in their assessment.
> >
> > At what point in the life cycle of a fossil fuel electric generation plant
> > does it's carbon footprint become net level with that of a conventional
> > solar or wind generator?
> >
> > Does 'never' work for you? 'Never' works for me.
> The point is that until sun and wind are guaranteed to be present in
> sufficient quantities to meet all energy needs the fossil fuel plant needs
> to be built regardless (negating a reactor, of course), thus rendering its
> construction costs moot to this argument.
> Whereas the solar panels and windmills are being touted for their low carbon
> footprint, lower overall pollution, and financial benefits, and therefore
> have to justify themselves by overcoming their construction costs.
> Eventually.
> Further question to ponder: A PBS documentary I watched claimed current
> solar electric panels were about 20% efficient.
More like 15% actually and 7% for the 'breakthrough' cheaper thin film ones.
> If my gradeschool science
> holds up that would mean that about 80% of the sunlight striking a black
> solar panel is converted into heat!
Correct, and that heat reduces the efficiency of the PV panel too.
> That being the case, if reducing Global
> Warming is your goal, wouldn't it make more sense to lay down mirrors
> instead of solar panels?
Look at this.
http://en.wikipedia.org/wiki/PS10_solar_power_tower
All done with mirrors and conventional steam generation.
Graham
XML site map
> My point wasn't a mass scale solution for Global Warming, but rather
> that any individual trying to cut Global Warming by installing solar
> panels would be better off laying down an equal amount of mirrors
> instead, as in their current state solar panels directly generate heat
> in what is likely a greater amount than they can counteract.
>
> LG