Posted by user on April 26, 2009, 12:26 am
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?
>>
>> --Winston
>>
>> --
>>
>> 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. If my gradeschool
> science holds up that would mean that about 80% of the sunlight striking
> a black solar panel is converted into heat! 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?
>
> LG
Nope, run pipe up the back and use the hot water to run sterling cycle
generators, heat buildings etc.....
Posted by Eeyore on April 24, 2009, 9:15 pm
Winston 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?
Depends on its design.
The UK designed the 'fluidised bed' generator which even today is the best
classic fossil fuel generator.
Flue desulphurisation can remit bad effects on plants. Increased CO2 increases
plant fertility and crop results.
Atmospheric CO2 levels are a sideshow. They have no effect on global warming
or cooling, and we're cooling now. Haven't you noticed ?
Graham
Posted by Morris Dovey on April 24, 2009, 6:39 pm
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.
While it's probably true that all manufactured artifacts are front
loaded with /some/ kind of energy consumption, I think the source(s) of
that energy are increasingly a matter of choice.
As regards the point at which devices reach the energy payback point, I
think you may be painting with a too-broad brush.
--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/solar.html
Posted by Eeyore on April 24, 2009, 8:56 pm
Frank wrote:
> Eeyore wrote:
> > "misterfact@yahoo.com" wrote:
> >
> >> can this type of mis-information, heard by millions of radio
> >> listeners, hurt the wind electric generator industry and the pv panel
> >> industry? :
> >>
> >> Talk show host #1:
> >>
> >> "Using wind-electric generators and solar panels as BACKUP systems to
> >> fossil fuel electric generation- produces more greenhouse gases than
> >> using fossil fuel generation alone!"
> >
> > I've never heard of them being used as BACKUP but he's probably right
> > since you wouldn't be using their full potential which makes them even
> > worse than usual producers of electricity compared to conventional.
> >
> >> Talk show host #2
> >>
> >> "Solar panels and wind electric generators put out a bigger carbon
> >> and pollution footprint than burning coal and natural gas in an
> >> elecxtric plant."
> >
> > Talk host #2 is being truthful about certain home mounted wind turbines.
> > http://www.guardian.co.uk/business/2009/feb/06/windpower
> >
> > " B&Q, the DIY chain, has withdrawn wind turbines from sale amid evidence
> > they do not work as efficiently as had been thought. The £1,900
> > micro-turbines went on sale at the 320-store chain in October 2006. The
> > company said they would generate up to 1kW of electricity, wired directly
> > into a ring main to reduce the amount of power a household needed to buy.
> >
> > But last month a survey by energy consultants Encraft warned that home
> > turbines generated only a fraction of the energy promised by
> > manufacturers, and in some cases used more electricity than they made.
> >
> > The results of the study, which tested different types of turbines in
> > different locations, showed the worst performing devices provided less
> > energy than needed for a conventional lightbulb for an hour, or even to
> > power the turbine's own electronics. "
> >
> > In the latter case net energy NEGATIVE !
> >
> > Graham
> 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.
Agreed. I'd like to see the energy impact analysis for this, but this method
seems to have been dropped by the greens when they reckon they have something
that's 'so good to be true'. How about some science to see if it is or not ?
> At this point, I'd say the talk show hosts are correct in their assessment.
I believe they were factually correct taking into account all circumstances.
Graham
Posted by Frank on April 24, 2009, 9:56 pm
Eeyore wrote:
>
>> Eeyore wrote:
> Agreed. I'd like to see the energy impact analysis for this, but this method
> seems to have been dropped by the greens when they reckon they have something
> that's 'so good to be true'. How about some science to see if it is or not ?
>
>
That's a point I try to get across. The ethanol debacle is a case in
point where you hardly get more fuel value from the ethanol than the
energy required to produce it. Add unanticipated increase in food
prices and you have a greenie legislated mess. These things are forced
on us by those without technical backgrounds or fundamental engineering
knowledge.
I read somewhere recently that a new solar electric investment would
have a payback period of 6 years and that's with 50% government subsidy
but about 2 years ago a full story on a documented installation by local
paper said 30 years even with subsidy. This is way past my age/life
expectancy. Plus my house is over 30 years old and every single major
appliance has had to be replaced including furnace and central air.
XML site map
>> 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?
>>
>> --Winston
>>
>> --
>>
>> 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. If my gradeschool
> science holds up that would mean that about 80% of the sunlight striking
> a black solar panel is converted into heat! 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?
>
> LG