Request: Accurate cradle to grave costs of fuels wanted

[CptHk]

Due to increase talk of energy/fuels in the general news, I want to be able to do a quick fact check when I see an article claiming one thing or another. If I get to use this for my work that would be a bonus.

I'm looking to be able to compare all types of energy production on a BTU expended, BTU available basis.

Has anyone seen an accurate breakdown or at the very least a semi-accurate ball park figure of cradle to grave costs of different fuels: natural gas, coal, oil, nuclear, hydro, solar, etc... I'm going to put a spreadsheet together for my own use, but before I re-create the wheel, does anyone have any information or links to information on this?

An example of what I am looking for: It takes X BTU's per 1 BTU of natural gas at the customers meter when considering all drilling and distribution losses to get natural gas piped from the Gulf of Mexico to New York City, for example.

Since nuclear, coal, hydro, and solar are only used to create electricity, it is okay to give just energy required to construct, install, produce, and maitain the generation plant.

I know there are different ways of looking at when does the support system stop, but as long as the data source indicates what is included and its designated amount then I can try to compare apples to apples. For example, some people like to include Defense spending in the oil equation, I'm fine with info like that as long as I know what portion they applied to the Defense spending. Again I am not looking for $ cost, but BTU amount.

 

[GMcD]

Good luck with that. Many of the "life cycle costs" calculation discussions I have with building designers struggle with the "where to start the baseline". For example- to get that cubic foot of natural gas out of the ground- do you start the costs at the point where the rubber gets vulcanized that goes onto the truck that hauls the drilling rig to the site to begin drilling? Do you include the embodied energy in the drill mud, the steel in the drilling rig, and drill pipes?, the embodied energy of the diamond drill bit used to poke the hole down to get the gas? You can see that the "true total cost" to extract a Btu of natural gas could be an absolute bear to try to account for all of the direct and indirect costs to get it out of the ground and spurting out your gas meter. Do you include the embodied energy of the steel pipeline, the materials in the compressors? The rubber tires on the trucks that drove the compressor from the factory to the site? The rubber tires on the trucks that hauled the parts to the compressor manufacturer to make the compressor? The salaries of the workers who assembled the compressor?

The point is, you need to draw an acceptable baseline from which to start accounting for the costs of energy creation/extraction, and I haven't found any real agreement on that yet.

 

[CptHk]

Thanks GMcD, I did assume what you spoke of might be the biggest problem. But has anyone seen any breakdown that is somewhat more inclusive than just the gas through the pipe to the meter?

Just to touch on one of your examples: the energy to manufacture and install the compressor you mentioned, it's got to be less than 1% of the total deal, think of the gazillions of cubic feet it must pump over its life. The energy to produce that component has got to be too tiny to make a blip in the overall parasitic losses that exist in the operation, surely some expert has compiled all the relevant numbers. And even if it is as tiny as I suggest, someone intimate with the industry would roughly know that cost.

 

[GMcD]

Yeah, I know a lot of those embodied energy costs may be small, but there are a LOT of them, and a lot of small things can add up to fairly significant numbers. But anyway, I'm not aware of any specific studies or attempts to summate the energy required to produce certain energy fuels, but you could be the first! Maybe start with the drilling rig getting on site and start adding from there, same for the wind generator getting raised. But you'll find a million gnit-pickers who will want to take you to task for whatever baseline you choose.

The trouble is that the cost of energy delivery is also directly proportional to the distance over which it's being delivered. So how would one allow for that?

 

[SomptingGuy]

Even automotoive "Well to Wheels" studies (

http://ies.jrc.cec.eu.int/wtw.html

) require an awfull lot of assumptions. They do make interesting reading though.

 

[electricpete]

I agree with GMcD on the comment "Good luck with that". The grey areas seem abundant.

Your question also seems somewhat nebulous to me. What would be some examples of conclusions you might draw if you had exact data for your question?

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

 

[CptHk]

SomptingGuy,

Although not exactly what I was looking for, I think if I dig into it I might get something.

GMcD and electricpete,

I'm not looking to write a thesis or argue energy policy, I just want to know the ballpark numbers. For example, do you know if it takes 1.1 Btu's for every 1 Btu of natural gas at the customer meter or 2.0 Btu's, or somewhere between or higher? I have no idea about the ballpark figures and just want a decent idea.

At a past job, we were involved with small scale distributed generation, usually with heat recovery. It would take me less than 2 hours to give a ballpark number of what our parasitic losses were for installation, service, operation, and maintenance, and the kwhr and btuh output. I could easily include down to the miles travelled on our vehicles per kwhr produced. I could even estimate the amount of copper fittings used, but I think I can also figure out when the order a magnitude of certain items gets so low that I could just estimate all other miscellaneous items = x% total loss. I'm assuming someone else has already done this for the major fuel/power generation sources.

 

[owg]

For a reasonable set of assumptions, download the report "Climate Friendly Hydrogen Fuel" from my website, see below. For an analysis that even includes the fuel used by the guys driving to work to run the plant, see various papers by Patzek including Thermodynamics of the Corn-Ethanol Biofuel Cycle. Google Patzek.

HAZOP at

http://www.curryhydrocarbons.ca

 

[dcasto]

Here's a piece of info on natural gas. For every 100 miles we move natural gas, it takes .5% of its energy. Typically, it takes about 5% of its energy just to get it started on its trip to the house., so a 1000 mile trip from Texas to Chicago, it costs about 10%. There is also about 3% of the energy used if the gas goes through storage. We produce gas all summer and save it until winter, so add that on.

 

[kenvlach]

The paper 'Thermodynamics of the Corn-Ethanol Biofuel Cycle' by Prof. Patzek is at

http://petroleum.berkeley.edu/papers/patzek/CRPS416-Patzek-Web.pdf

Be aware that Prof. Patzek is a thoroughly biased, petroleum consultant and a petroleum industry's 'Man of the Year' (1995 if I recall right). His farming model is strip mining (his original field of study) rather than sustainable agriculture.
[Although I agree that a lot of corn is grown on a non-sustainable basis, contributing to erosion & the 'dead zone' in the Gulf of Mexico, sucking up a taxpayer subsidy of 50 cents/gallon and costing consumers a hidden tax in higher food prices.]
For more of a critique, from Argonne National Lab, see
eerc.ra.utk.edu/etcfc/docs/pr/MichaelWangResponse~7-19-05.doc

Prof. Patzek picked up an agriculture professor, 'world-famous' professor David Pimentel of Cornell, as co-author on some publications to gain some credibility, but Pimentel seems to be an entomologist (insect guy) with limited practical knowledge of agricultural.

 

[0707]

for energy costs go to

http://www.eia.doe.gov/emeu/international/electricityprice.html

For energy a related BTU amount

go to

https://energy.navy.mil/publications/pnl/fueltype.doc

http://housing.cce.cornell.edu/f-sht-pdf libraries/HOUSING F-SHTS/hvac-pdfs/comparing heat%

20fuels.pdf

http://www.doa.state.wi.us/docs_view2.asp?docid=778

luismarques

 

[owg]

CptHk has posed a challenging question. As yet there is no rigour in the various estimates so this list is based on quicksand. However here is a start. The reference is

http://slate.com/id/2122961/

A US gallon of ethanol contains 76,000 BTU, probably the high heating value. According to Patzek and Pimenthal it takes 98,000 BTU of energy to make the gallon of ethanol, much of this coming from fossil fuels.

A US gallon of gasoline contains 116,000 BTU. To find the well, transport and refine the fuel requires 22,000 BTU. If you make the gasoline from tar sands, you need about 60,000 BTU of energy.

Now all that needs to be done is to complete this list for coal, nuclear, PV, etc. after putting the calculations on a consistent basis. As has been stated earlier on this thread, Good Luck! Maybe a first step, to generate interest, would be to tabulate the data on a non-rigorous basis. Google finds references for PV and for nuclear without too much digging. One interesting parameter used in the PV reference was the number of years it takes to get the energy to construct back. It looks like it takes a few years.


HAZOP at

http://www.curryhydrocarbons.ca

 

[epoisses]

owg,
Hmm... the complicated bit would be converting BTU spent into cradle to grave cost, which is not at all the same correlation in different cases.
BTUs required in oil refining to produce gasoline are very easily = cheaply obtained by burning part of the oil (fuel or fuelgas).
BTUs required to generate a BTU of solar energy are (1) very difficult to quantify and (2) very difficult to convert into cost. So difficult that I would tend to believe that it does not even makes sense to take the BTUs required into account, but rather correlate BTUs produced to money spent directly.
BTW how do you factor in that refinery facilities have usually been written off long ago (gasoline usually comes out of a '50s style "vintage" naphtha reformer) while R&D is still a major part of the cost of solar.

 

[owg]

epoisses - You are correct, the bases for all the calculations should include estimates of the energy used to construct, including that old reformer. However my preference would be to avoid cost estimates and stay with BTUs. This is one of the key issues separating the farmers and government from Patzek and Pimentel. The farmers want to sell the byproduct from the ethanol plant and buy fuel. So the analyis starts to depend on the relative prices of cattle feed and natural gas.

HAZOP at

http://www.curryhydrocarbons.ca

 

[kenvlach]

As I pointed out, Patzek is a biased, petroleum industry propagandist. But, ethanol from corn still isn't that practical, nowhere near as good as soybean oil fuel in terms of energy balance:

The US National Academy of Sciences (Proceedings, July 11, 2006):
"The first comprehensive analysis of the full life cycles of soybean biodiesel and corn grain ethanol shows that biodiesel has much less of an impact on the environment and a much higher net energy benefit than corn ethanol, but that neither can do much to meet U.S. energy demand.
...
The study showed that both corn grain ethanol and soybean biodiesel produce more energy than is needed to grow the crops and convert them into biofuels. This finding refutes other studies claiming that these biofuels require more energy to produce than they provide. The amount of energy each returns differs greatly, however. Soybean biodiesel returns 93 percent more energy than is used to produce it, while corn grain ethanol currently provides only 25 percent more energy."

http://www.pnas.org/cgi/content/full/103/30/11206

Also, soybean biodiesel (from soybean oil) has a valuable byproduct, high-protein soybean meal.

 

[Amphoteric]

As mentioned above everyone can get a different answer on this topic. Nevertheless, here's a summary list of "Energy returned on energy invested." The concept is, if I spent 30 BTU to generate 60, by EROI is 2:1. At least this is referenceable.

http://www.eroei.com/eroei/evaluations/net_energy_list/

You can see fossil fuels and hydro are the standouts. Nuclear/wind and maybe solar is ok, while biofuels are barely positive. I've read that cellulose ethanol is expected to be in the range of 4-5 someday, but hard to say.

One thing you'll note is that the EROI for fossil fuels decreases over time. We are forced to tap more and more difficult assets (which overwhelms the gains in efficiency we make from better technology). Some stripper wells in the US spend more energy than they make pulling up dregs of oil, but it's worth it because oil is so valueable.

 

[Amphoteric]

Sorry, thought of something to add. If you've got access to technical journals, this is a fantastic summary on the state of ethanol's pro/cons. (Energy, emissions, everything).

Kiven, Robert K. “Ethanol in gasoline: environmental impacts and sustainability review article.”
Renewable and Sustainable Energy Reviews. Volume 9 (2005), Issue 6, pp 535-555

 

[CptHk]

Thanks to everybody for the posts so far. At least I now have a starting point and to some extent I know better what is included in the "costs".

Unfortunately I think it is going to take more of my free time than expected.