by Googolplex » Thu 15 Sep 2005, 01:48:24
$this->bbcode_second_pass_quote('Optimist', '')$this->bbcode_second_pass_quote('', 'I')t still consumes more energy from our available reserves to convert that waste then it produces as oil.
Excuse me, but you are talking through your nose. Now, I suspect the energy balance in the following link:
Click . see Figure 6 on page 8 is out of date and not 100% accurate. As the best available information on TDP it would have to do, though.
Energy input (as electricity): 3.6 MM BTU/h. Energy output (as TDP 40 oil, ignoring other output): 99.5 MM BTU/h. ERoEI = 99.5/3.6 = 27.6!p
I draw your attention now, as before, to page 9 sentence 1. The energy efficiency for the process is 85% according to the document you quoted. Thats an EROEI of 0.85, and thats less then 1.
Let me make this simple:
There is a certain amount of oil, gas, minerals, etc, that is in our waste. TDP uses energy from our current supply to free that stuff from our waste. Its still the same amount though. TDP does not produce more stuff then was already in our waste, even though we have to invest extra energy
in addition to the input waste. We can then use that stuff we extracted to produce more energy and goods, and therefore more waste, but not quite as much as before, because some of our energy was lost the first time around when we made the initial waste, as well as during the only 85% efficient TDP process. So now we have less waste this time, which means less stuff extracted in the next go through the TDP plant, which also consumes even more additional energy from our reduced supplies to work.
So not only do we loose 15% with every go through the TDP plant, as the document you quoted clearly states, but you have to include the energy loss when we use the resulting stuff from the TDP plant to produce more waste, which is probably MUCH worse then 85%.
by bruss01 » Thu 15 Sep 2005, 13:00:01
$this->bbcode_second_pass_quote('frost667', '')$this->bbcode_second_pass_quote('Googolplex', 'R')est easy animal lovers! It should run just as well on dead people too!

If things go really bad there will be much more dead humans than dead cats, I suppose...
But thanks for your input, it made me smile.
"Soylent Diesel is.... People!!!"
Turns out Soylent Green is just boogers.
by Optimist » Fri 16 Sep 2005, 20:47:46
$this->bbcode_second_pass_quote('', 'S')o not only do we loose 15% with every go through the TDP plant, as the document you quoted clearly states, but you have to include the energy loss when we use the resulting stuff from the TDP plant to produce more waste, which is probably MUCH worse then 85%.
Oh, aren't we CLEVER? OK, smart guy, name one other process that even claims 85% efficiency. It is a pretty bold claim to make. Of course 85% is not 100%, but we should not be holding up 100% as the gold standard. Nothing can be done @ 100% efficiency. So why measure TDP against the unattainable?
In reality we should compare the 85% to the 0% recovery of the energy in the waste that we currently achieve. It should be obvious that 85% is better than 0%.
$this->bbcode_second_pass_quote('', 'T')here is a certain amount of oil, gas, minerals, etc, that is in our waste.
WRONG again. How much of the carbon that makes up a turkey (and its guts) came from oil or gas? Hint: its a number mentioned above. Answer: 0%. 100% of the turkey substrate comes from PLANT matter. The plant matter came from SUNLIGHT and CO2. Hint: can you say SUSTAINABLE ENERGY?
by Googolplex » Sat 17 Sep 2005, 07:08:13
$this->bbcode_second_pass_quote('Optimist', 'O')h, aren't we CLEVER?
Not particularly I don't think. Its not that difficult a concept to grasp really.
$this->bbcode_second_pass_quote('', 'O')K, smart guy, name one other process that even claims 85% efficiency. It is a pretty bold claim to make. Of course 85% is not 100%, but we should not be holding up 100% as the gold standard. Nothing can be done @ 100% efficiency. So why measure TDP against the unattainable?
If you are reffering to the efficiency of an energy source, which is more correctly termed its EROEI, or 'energy returned on energy invested' then I can assure you that ALL energy sources are over 100%. In fact, thats the very deffinition. Otherwise, how could it produce surplus energy if it consumed more then it produced?
If you are reffering to the efficiency of an energy
conversion, such as an engine, or the TDP process, well of course it can't be 100% or more efficient! If it were, it would be an energy source!
$this->bbcode_second_pass_quote('', 'I')n reality we should compare the 85% to the 0% recovery of the energy in the waste that we currently achieve. It should be obvious that 85% is better than 0%.
TDP does not convert 85% of our waste to energy. The 85% figure reffers to the net energy we have left over (in the form of the oil and gas outout from the plant) as a portion of the energy invested into the process in the first place, and that DOESN'T include the waste itself.
In reality, we should look at all the energy wasted by turning our waste into oil, and consider wether it might be better invested elsewhere.
$this->bbcode_second_pass_quote('', '')$this->bbcode_second_pass_quote('', 'T')here is a certain amount of oil, gas, minerals, etc, that is in our waste.
by Optimist » Mon 19 Sep 2005, 14:28:06
$this->bbcode_second_pass_quote('', 'I')f you are reffering to the efficiency of an energy source, which is more correctly termed its EROEI, or 'energy returned on energy invested' then I can assure you that ALL energy sources are over 100%. In fact, thats the very deffinition. Otherwise, how could it produce surplus energy if it consumed more then it produced?
If you are reffering to the efficiency of an energy conversion, such as an engine, or the TDP process, well of course it can't be 100% or more efficient! If it were, it would be an energy source!
You are getting tripped up in your cleverness, smart guy. You either have to include the energy in the fuel (feedstock) in the analysis, in which case no process, be it drilling for oil or TDP or whatever will have an ERoEI of more than 1. Or you can exclude the energy in the fuel, in which case many processes have an ERoEI of more than 1, including TDP.
$this->bbcode_second_pass_quote('', 'T')DP does not convert 85% of our waste to energy. The 85% figure reffers to the net energy we have left over (in the form of the oil and gas outout from the plant) as a portion of the energy invested into the process in the first place, and that DOESN'T include the waste itself.
You obviously do not understand the TDP process, which explains many of your comments. Take a few minutes. Go to the referenced paper
CONVERTING TURKEY OFFAL INTO BIO-DERIVED HYDROCARBON OIL see Figure 6 on page 8. Look at the numbers. To summarize:
INPUT: 122.9 MM BTU/h (as WASTE), 3.6 MM BTU/h as electricity.
OUTPUT: 99.5 MM BTU/h as TDP-40 oil, 6.4 MM BTU/h as carbon, 1.4 MM BTU/h as fuel gas.
The energy in the waste is
obviously INCLUDED (Hint: it is the 122.9 MM BTU/h).
For the sake of clarity:
ERoEI = 99.5/3.6 = 27.6 [only taking credit for TDP-40 oil]
Efficiency = 99.5/(122.9 + 3.6) = 78.7% [oil only]
CWT Efficiency = (99.5 + 6.4 + 1.4)/(122.9 + 3.6) = 84.8% [all products]
by Optimist » Mon 19 Sep 2005, 21:43:54
$this->bbcode_second_pass_quote('', 'W')ow. Ive never seen such an example of flinging numbers around that one doens't understand. Sorry about the lateness of my reply BTW.
I'll take the lateness of the reply as an indication of your inability to address the underlying realities.
$this->bbcode_second_pass_quote('', 'T')he total EROEI of coal is not 15-20%. According to the figures Ive found, its somewhere around 30:1, or 3000%, and that includes the 15-20% efficiency of burning it. Compare that to the 85% of TDP!
Oh, yeah? Where did you find these figures? In your dreams? I see no link or reference. Try again, Sam.
$this->bbcode_second_pass_quote('', 'Y')ou see, the energy in coal, or oil, or any fossile fuel, is already there, ready for use. We don't have to "invest" it. We only need to transport it to where we need it and burn it (or do whatever). Thats why its a source of energy.
You mean like waste? Or wait, waste already get transported to central disposal facilities, so it is one step ahead of fossil fuels.
$this->bbcode_second_pass_quote('', 'N')ow, we COULD then turn around and take all that energy we get from the coal and use it for TDP, but the oil and gas we get back out would only equal 85% of the energy invested,
which itself is only 15-20% of the energy in the coal. So if you have a TDP plant powered by coal, for every 1 unit of energy in coal that you consume, you get only 13-17% back, or somewhere around 0.1275 and 0.17 units back.
by Googolplex » Tue 20 Sep 2005, 17:45:42
$this->bbcode_second_pass_quote('Optimist', 'Y')ou are getting tripped up in your cleverness, smart guy.
Honestly, you sound awfully rediculous when you say that. Its like calling someone a nerd for using a computer, while you sit in front of the computer next too him.
$this->bbcode_second_pass_quote('Optimist', 'Y')ou either have to include the energy in the fuel (feedstock) in the analysis, in which case no process, be it drilling for oil or TDP or whatever will have an ERoEI of more than 1. Or you can exclude the energy in the fuel,
Of course. In fact, to include it would be entirely incorrect in most cases, as your numbers wouldn't really tell you much about wether its a good energy source or not at that point. Its the extraction/generation of that fuel/enegergy that matters, i.e. making energy we can use. Unfortunatly, the exception is TDP, as I explain below.
$this->bbcode_second_pass_quote('', 'i')n which case many processes have an ERoEI of more than 1, including TDP.
<strike>It most certainly does not. That is what I have been saying, and have pointed out in the paper. I have also seen it from many other sources. The EROEI is 0.85, not more then 1.</strike>
[Actually, thats not entirly correct. It seems Ive made a mistake...

]
$this->bbcode_second_pass_quote('', 'Y')ou obviously do not understand the TDP process, which explains many of your comments. Take a few minutes. Go to the referenced paper
CONVERTING TURKEY OFFAL INTO BIO-DERIVED HYDROCARBON OIL see Figure 6 on page 8. Look at the numbers. To summarize:
INPUT: 122.9 MM BTU/h (as WASTE), 3.6 MM BTU/h as electricity.
OUTPUT: 99.5 MM BTU/h as TDP-40 oil, 6.4 MM BTU/h as carbon, 1.4 MM BTU/h as fuel gas.
The energy in the waste is
obviously INCLUDED (Hint: it is the 122.9 MM BTU/h).
For the sake of clarity:
ERoEI = 99.5/3.6 = 27.6 [only taking credit for TDP-40 oil]
Efficiency = 99.5/(122.9 + 3.6) = 78.7% [oil only]
CWT Efficiency = (99.5 + 6.4 + 1.4)/(122.9 + 3.6) = 84.8% [all products]
by Googolplex » Tue 20 Sep 2005, 21:04:17
$this->bbcode_second_pass_quote('Hermes', '')$this->bbcode_second_pass_quote('Googolplex', '
')
I should still point out that the over all point, its unsustainability, is not in question however, and I will not concede it.
I
almost agree with you on this one Googolplex. What I wish you had perhaps said was "This will not save us from Peak Oil" in which case I would have absolutely agreed with you.
If it turns out that this process can take organically grown vegetable matter (product of earth's minerals, solar energy, oxygen NO fossil fuel fertilizers + pesticides) and turn them into a large amount of oil...AND that amount of oil warrants constructing/maintaining the mechanism as well as transporting/growing the vegetable matter...
Then I would be of the opinion that it acually
IS sustainable.
Oh my yes. I am having a bad day today, arn't I?
TDP that consumes waste is so hyped, that I hadn't even considered that biological material that was
not waste could be used. In fact, how exactly DOES the process of turning crops like rape seed into bio-fuels work? Could this turn out to be a more efficent method? Worth a bit of investigation...
$this->bbcode_second_pass_quote('', 'H')owever sustainable or not it will only have the ability to steer us towards a slow crash-soft landing. We will still NOT be able to produce the amounts of oil and quickly enough to keep our way of life going with this technology, for many reasons.
Of course. I suspect Optimist would agree too. TDP is obviously more useful then I used to think, but it clearly is no subsitute for the trillion barrels of free energy that have been litterally bursting from the ground the last 150 years.

$this->bbcode_second_pass_quote('', 'O')n a personal note I'm glad of this. I welcome the peak. I just hope it's a soft landing...
That said though: I'm not convinced that this technology certainly
WILLmake the soft landing happen either, I'm just saying that I think that if it's adopted it should help to keep the slope of that downwards curve less steep.
by Googolplex » Tue 20 Sep 2005, 21:17:48
$this->bbcode_second_pass_quote('Caoimhan', 'B')ut there is a tendency for people on these forums to make a straw man argument that since a particular technology can't solve all our problems, it's not worth doing.
I know exactly what you mean. Sometimes it seems like people just don't
want to hear anything but "complete colapse" and "massive die off", like they're rooting for it.
$this->bbcode_second_pass_quote('', 'I')s TDP worth doing? Certainly! So is wind, solar, nuclear, tidal, geothermal, bio-fuels, and maybe even hydrogen (I've been seeing some ingenious methods lately that solve the H2 transportation problem).
TDP will almost certainly hold a share of our future energy "production". Just how large that share will be is the question.
Indeed. My opinion is obviously that it will most likely be a pretty small share, as Ive always believed, but hey, I could definatly be wrong. Now that I know the correct numbers, its already looking better.

by Optimist » Tue 20 Sep 2005, 22:24:13
$this->bbcode_second_pass_quote('', '[')Actually, thats not entirly correct. It seems Ive made a mistake... ]
My hat's off to you, Googolplex. It takes a set of big ones to admit a mistake like that.
$this->bbcode_second_pass_quote('', 'I') should still point out that the over all point, its unsustainability, is not in question however, and I will not concede it.
Ah, the debate moves on to sustainability...
$this->bbcode_second_pass_quote('', 'B')esides, we will always need more energy then is available in the waste we produce, because the waste is a byproduct of our use of the energy.
Yes but no. Let's see if we can summarize our different views on this:
Your view: ENERGY1 => USEFUL PRODUCTS + WASTE.
WASTE => (via TDP) => ENERGY2.
Since ENERGY2 ~ 85% of WASTE and WASTE < ENERGY1, ENERGY2 < ENERGY1, and the system cannot sustain itself.
My view: SOLAR ENERGY => (via PHOTOSYNTHESIS) => FOOD + WASTE1.
FOOD => (via PEOPLE) => LOST ENERGY + WASTE2.
ENERGY1 => USEFUL PRODUCTS + WASTE3.
WASTE1 + WASTE2 + WASTE3 => (via TDP) => ENERGY2.
Now, ENERGY2
can be > ENERGY1. WASTE2 + WASTE3 is probably a small number. Let us assume WASTE2 + WASTE3 = 5% of WASTE1. In other words WASTE1 + WASTE2 + WASTE3 = 1.05 x WASTE1. For the system to work 1.05 x WASTE1 > ENERGY1/0.85, or WASTE1 > 1.12 ENERGY1.
There are, of course, two ways to make that system work:
1. Increase PHOTOSYNTHESIS until we have enough feedstock.
2. Reduce our energy consumption (ENERGY1) until it works.
We peobably need to do some of both, to get to the optimal solution. I'm out of time here, but I think there is enough PHOTOSYNTHESIS to make this work, without completely giving up our convenient lifestyles.
by Googolplex » Wed 21 Sep 2005, 04:49:36
$this->bbcode_second_pass_quote('Optimist', 'T')here are, of course, two ways to make that system work:
1. Increase PHOTOSYNTHESIS until we have enough feedstock.
2. Reduce our energy consumption (ENERGY1) until it works.
We peobably need to do some of both, to get to the optimal solution.
Well, you are mostly correct here. As you'll see in my response to Hermes, I did indeed restrict my thinking to narrowly in regards to the sources of feedstock. However, as I also pointed out in my last reply to you, the paper implies that the plants have to be built and tuned for specific feedstocks, at least in order to achieve that excellent efficiency, or possibly to work properly at all. We would most likly be talking about many different TDP plants to process each type of feedstock efficiently, and so our ability to reprocess large amounts of greatly varied waste would be rather restricted by our ability to build lots of large, expensive, and appearently smelly TDP plants all over the place.
$this->bbcode_second_pass_quote('', 'I')'m out of time here, but I think there is enough PHOTOSYNTHESIS to make this work, without completely giving up our convenient lifestyles.
Well I don't know about that. Our lifestyles are pretty damned convenient! Even if your most optimistic (pun intended

) hopes regarding TDP were true, I still would be suprised if we weren't required to 'power down' by a more then noticable amount. We'll see though!

by Googolplex » Thu 22 Sep 2005, 01:52:47
$this->bbcode_second_pass_quote('Drjay', 'G')ood discussion. However, when we think of the impact that all this "free" energy is now having upon our world, is it so free?
Obviously I didn't mean it was litterally free.

There is the need to transport and refine it.
The cost that you reffer to however, I think is only fair to lay at our own feet. That impact is a consequence of our ignorant oil binging, not inherent in the oil itself. We COULD have used the oil differently, and avoided our current situation.
$this->bbcode_second_pass_quote('', 'A')lso, There is a energy cost associated with PV cells, what did it cost in power to produce the cell originally? I have read (which intrepreted is I have not investegated yet) that it takes more total power to produce a PV cell than it will generate over its life time. I wonder just how true that is?
Its not as far as I know. I don't remember specific sources, but from what I have read, the EROEI on photovoltaics is in fact positive, despite what some have claimed in the past. Im not sure that the subject of PV cells really belongs in this thread though... weren't we talking about thermal depolymerization?