Jump to content

Talk:Energy return on investment/Archive 1

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia
Archive 1

Edits 12/24/2007

'Acceptance outside physics' section removed. This section, as written, is condescending and tautological in regard to all information presented other than opinion. For example, the statement "Geology and thermodynamics are much more fundamental to the world than economics." is not a factual statement given the lack of qualifiers inherent to the phrase 'more fundamental to the world' -- the question 'more fundamental to the world in what way?' is begged. In terms of describing how the world's economy works, neither geology nor thermodynamics, neither of which involve the study of the world's economy, would be likely to be 'more fundamental'. —Preceding unsigned comment added by 170.3.8.253 (talkcontribs) 16:30, 24 December 2007

The laws of physics are "fundamental" in the sense that no human activity can violate the laws of physics. For example, we know the amount of petroleum in the ground must be finite, and furthermore the practicality of extracting various deposits of petroleum depends on geological and chemical factors. If an economic theory disregards the underlying science, and declares petroleum supply to be solely a function of financial investment, that theory must eventually fail as the easier petroleum deposits become depleted. At some point the ground in a given area (and eventually throughout the whole world) will fail to yield more petroleum regardless of investment. Similarly, no one has been able to produce flying carpets or build perpetual motion machines simply by investing enough money, which suggests that nature cannot be fooled. As to whether this makes physics "more" fundamental than economics, that would depend on the context. Physicists themselves work for paychecks and often rely on generous government funding to build particle accelerators and other expensive equipment, and thus they are personally at the mercy of economics, just as economic principles are subject to the laws of physics. Arguing about which is "more" fundamental might be most relevant to one-upmanship at faculty parties. See also Reductionism. --Teratornis (talk) 21:36, 8 May 2009 (UTC)

EROEI Values

Are these EROEI values given (3 for US and 10 for Saudi) supportable?

Cleveland and Kaufmann's latest work suggests an EROEI of around 10 for the US today, and Saudi Arabia will by extension by much higher. See the net energy page on www.oilanalytics.org, though the website appears to be down at present. 61.69.2.156 09:21, 26 November 2005 (UTC)


The values definitely seem low, but the language used is worse. I'm going to change it so it's a bit clearer.

User:Renaissance Man removed a link to oilanalytics.org, once a legitimate site, but apparently now under new ownership. --C J Cowie 19:58, 10 December 2005 (UTC)

I found a cache of the correct page and restored the link. Linkspro 01:25, 16 December 2005 (UTC)

A broken link points to a danish site as reference. How long should there go before I can delete this link (I am newbie to this), but want to help out. iversen7 —Preceding undated comment added 18:15, 25 August 2011 (UTC).

Removed Sites Requiring Registration

Per WP:EL guidelines, removed 2 links that require registration to enter. Calltech 11:49, 25 November 2006 (UTC)

Fusion Power

Should the development of fusion power be mentioned? The focus of research in the field is to create an EROEI above one (currently only about 0.5). 71.103.22.71 01:28, 18 March 2007 (UTC)

Yes, mention it. It would make an excellent example of why EROEI is so important to consider when developing new sources of energy. Some people wonder why we can't switch to fusion if it's physically possible to build a reactor and environmentally more friendly, and the low EROEI is the answer to this. — Preceding unsigned comment added by 212.146.47.250 (talk)
On the other hand the entire subject of Energy Return on Investment is totally irrelevent. For example, if you are burning wood to boil off maple syrup and you find that it takes you more energy to obtain the wood than you get from the wood, in other words your EROEI is less than one you certainly do not change from using wood to make maple syrup, because that would ruin the maple syrup, it simply means that you are actually getting your energy from something else other than wood, ultimately. For example if you cut the wood by hand and hauled it by draft horse the primary energy source for making maple syrup is not the wood that you burned but the food you and the horses ate. Since matter and energy and all forms of energy can be converted one to another what is most important is not how efficient your source of energy is but the damage that would be done along the way by using that source of energy. 199.125.109.18 02:43, 1 August 2007 (UTC)
"Totally irrelevant" is a far-too-general dismissal. EROEI is a sensible way to evaluate alternative uses of the same form of energy. For example, if we want energy in the form of electricity, there are several ways to generate it from primary energy sources. We can burn a primary energy source such as coal in a thermal power plant, or we can burn primary energy sources to build wind turbines, to list just two options. It turns out that building a modern large wind turbine generates about 80 times as much electricity as burning an amount of fuel in a power plant equal to the total primary energy expenditure to build, maintain, and decommission/recycle the wind turbine at the end of its service life. In this case we comparing apples vs. apples, so EROEI is highly relevant. Think of the question as: what is the most electricity you can get from a ton of coal? --Teratornis (talk) 21:58, 8 May 2009 (UTC)

Table of comparison

We need a handy table summarizing/comparing the EROEI ranges for solar, wind, etc energy sources, with references. We need better external links.-69.87.199.117 12:56, 18 June 2007 (UTC)

How about a dot chart? Mrfebruary (talk) 09:33, 27 August 2011 (UTC)

Murphy, D. J. and Hall, C. A. S. (2010), Year in review — EROI or energy return on (energy) invested. Annals of the New York Academy of Sciences, 1185: 102–118. doi: 10.1111/j.1749-6632.2009.05282.x

The way the x axis is structured it makes comparison of the values at the bottom of the y axis difficult. Most of the values look very close to 0. Would be better if the x axis were stretched. Also, the title is EROI, which might be taken to mean dollar investment, not energy investment....picky, but you have to allow for dummies like me who need to read things 3 times before they understand them.

Avram Primack (talk) 18:09, 9 November 2011 (UTC)

On the x axis, the location of the value 1 seems much more important than the location of the value 0. Also, including any range below 0 seems undesirable. However, that plot does not show the location of the value 1. Using a logarithmic scale for the x axis seems like it would be a highly desirable modification. I suspect that the exact ratio for many of the energy sources that fall at the left end of the curve is probably a matter of substantial dispute and an opportunity for substantial estimation error. Finally, I suggest that including a point for hydrogen power would be highly desirable. My understanding is that its ratio is less than 1, and that hydrogen therefore should be considered more as a way of storing energy than as a way of producing it. —BarrelProof (talk) 18:01, 13 April 2012 (UTC)

Historical evidence

Thomas Homer-Dixon in "The Upside of Down" suggests that EROI analysis provides a basis for the analysis of the rise and fall of civilisations. Looking at the maximum extent of the Roman Empire, (60 million) and its technological base the agrarian base of Rome was about 1:12 per hectare for wheat and 1:27 for alfalfa (giving a 1:2.7 production for oxen). One can then use this to calculate the population of the Roman Empire required at its height, on the basis of about 2,500-3,00 calories per day per person. It comes out roughly equal to the area of food production at its height. But ecological damage (deforestation, soil fertility loss particularly in southern Spain, southern Italy, Sicily and especially north Africa saw a collapse in the system beginning in the 2nd century, as EROI began to fall. It bottomed in 1084 when Rome's population, which had peaked under Trajan at 1.5 million, was only 15,000. Evidence also fits the cycle of Mayan and Cambodian collapse too. Perhaps some comment on this work could be included. Regards John D. Croft 03:03, 14 August 2007 (UTC)

Patent nonsense ?

Energy return on Energy invested does not take into account the factor of time. Energy invested in creating a solar panel may have consumed energy from a high power source like coal, but the return happens very slowly, i.e. over many years. If energy is increasing in relative value this should favour delayed returns.

That is patent nonsense. Generally, in financial terms, getting something now is almost always preferable to getting it later. (There's exceptions: if you could get a basket of strawberries in Canada in january, that'd be more worth than getting the same berries 6 months -earlier-)

Investing 1 GJ worth of coal now, and get 1GJ worth back out over the next 10 years may be beneficial if the price of energy rises, but this is only true if you ignore the fact that this coal could simply be -stored- and then used later for energy-generation.

There is no need to convert the coal to solar-cells if the point is simply to get the energy -later- rather than -now-. --Eivind Kjørstad (talk) 12:34, 7 February 2008 (UTC)

Energy return on Energy invested does not take into account the factor of time: That's correct. Time is a financial consideration, not an energy consideration. Energy return doesn't take into account the factor of place, either, nor several other things.
The time consideration can go either way. For example, in a rechargable battery, you might put 100 watt hours into a battery, and get 50 watt hours out. That is an energy efficiency of only fifty percent-- but those 50 watt hours are taken out when and where you need them, and hence are much more valuable than the hundred watt hours you put in. Do you multiply the efficiency to account for this? No. Efficiency is energy out divided by energy in. Financial consideration are something different.
In short, Energy return on energy invested is one factor in energy economic analysis, but by no means the only one.Geoffrey.landis (talk) 14:53, 29 August 2008 (UTC)

Citation of Rome's population contradicts History of Rome article

In this article (http://en.wikipedia.org/wiki/History_of_Rome), it seems that the population of Rome bottomed out sometime in the 1300s, not in 1084 as this article states. —Preceding unsigned comment added by 98.207.114.147 (talk) 16:07, 1 April 2008 (UTC)

The follwing line appears among the external links

Well, the designation cogent is plain nonsense. Moreover, the referred page appears to be amateurish at best, outdated by ten years, and utterly unscientific: to get an idea, just look at the following exerpt.

NEARLY EVERYONE IS WRONG!<br\> Nearly everyone in the world (all governments, and all but a handful of scientists, etc.) has accepted the economists' perpetual-motion machine. Even the Energy Information Administration (EIA) of the USA Department of Energy has no idea how much energy is required to produce energy ("net energy"). Nor does the EIA have any idea how long energy can be produced ("peak")!

I delete the link. —Preceding unsigned comment added by 131.114.114.221 (talk) 16:08, 13 October 2009 (UTC)

Someone deleted the link although the statement about nearly everyone being wrong is true. Twayburn (talk) 10:49, 6 July 2013 (UTC)

Criticism section

This seems like an op-ed piece and doesn't belong in the article at all. Better to just delete the whole section for now.


Also, someone thinks that every rational conclusion that contradicts conventional "wisdom" (brainwashing) is opinion or worse. This is too important to let falsity persist only because the average person who is likely to edit this article knows so little and most of that is wrong. Twayburn (talk) 10:50, 6 July 2013 (UTC)

Topics needing coverage

  • Methodology
    I think I have seen someone use the term energy accounting to mean measurement and disclosure of information that is useful in making energy resource allocation decisions. EROEI is a term that seem to be analogous to the accounting term ROI (return on investment). It seems to me that a methodology for determining EROEI should be somewhat similar to ROI accounting methods.
  • Another energy accounting issue
    It is also important to know the complete energy usage required to perform a given task in a given way. For instance how much energy does it take to boil a liter of water on an electric stove as compared to a gas stove. That is similar to EROEI for energy delivered to the pan of water.
  • EROEI report
    Using accounting-like methodology, EROEI would not be presented as a bottom-line number but would include some kind of detailed "income statement."
  • References (I added one)

C J Cowie

It is not clear where the figures in the table come from, could someone add a clearer reference/clearer references? While the figures share similarity with those from the Murphy & Hall 2010 graph above, there are obviously some differences. Any clarification appreciated. Sunshinemachines (talk) 23:54, 8 July 2013 (UTC)

Problems with the Charles Hall and Murphy table

I recently had to delete some vandalism on the page, although it was clearly vandalism, the document the vandal included does bring up some important points about Solar's EROEI. I also find the graph of EROEI misleading in relation to Nuclear fission, as in the US uranium is now primarily enriched via centrifuge enrichment technology and not the older and more energy intensive gaseous diffusion enrichment, which is pretty much being entirely phased out in the US for the less energy intensive enrichment technologies, moreover the rest of the world has been using centrifuge enrichment for decades now.
This was the Solar document the vandal included, which deserves a read - http://www.bnl.gov/pv/files/pdf/241_Raugei_EROI_EP_revised_II_2012-03_VMF.pdf
Here is information on the drasticly different energy requirements and differences in general between the old and modern enrichment technologies, comparing diffusion enrichment and the centrifuge method, taken from a -Federation of American Scientists document. - The throughput per centrifuge unit is very small compared to that of a diffusion unit so small, in fact, that it is not compensated by the higher enrichment per unit. To produce the same amount of reactor-grade fuel requires a considerably larger number (approximately 50,000 to 500,000] of centrifuge units than diffusion units. This disadvantage, however, is outweighed by the considerably lower (by a factor of 20) energy consumption per SWU for the gas centrifuge. SWU stands for Separative work unit, Here's the document http://www.fas.org/sgp/othergov/doe/lanl/pubs/00416663.pdf
Boundarylayer (talk) 00:19, 10 April 2013 (UTC)

This data from Hall is very much out of date. The last diffusion plant closed in 2013. Today (2014) all capacity is centrifuge which has a life cycle (including energy to make the equipment) energy consumption of about 60 kWh/SWU versus diffusion of >2400 kWh/SWU. 40x lower lifecycle consumption than diffusion... Actual lifecycle analysis from real plants with real data shows EROEI of about 75 (eg Forsmark plant Environmental Product Declaration). Further improvements would be gained with more modern higher burnup plants...

It goes without saying that any EROEI estimate that assumes any amount of diffusion enrichment is out of date. Today is 100% centrifuge... Siphon06 (talk) 09:25, 1 October 2014 (UTC)

A further problem with that table is that two fundamentally different categories of energy carriers, namely (i) actual fuels (e.g. coal, oil, etc.) and (ii) electricity (wind, nuclear, photovoltaic, etc.) are listed together. However, producing electricity out of the listed fuels entails further energy investments (to build and operate the power plant) and losses (thermal-to-electrical energy conversion, governed by the 2nd law of thermodynamics). Therefore, it would be more meaningful to present two separate comparison tables, i.e. (1) for the actual fuels only (coal, oil, gas, etc.), and (2) for the various ways of producing electricity (wind, nuclear, photovoltaics, AND electricity from coal, electricity from oil, electricity from gas, etc.). — Preceding unsigned comment added by 161.73.149.112 (talk) 09:56, 2 October 2014 (UTC)

Wikitable EROEI - energy sources in 2013

EROEI energy sources in 2013
3.5 Biomass (corn)
3.9 Solar PV (Germany)
16 Wind (E-66 turbine)
19 Solar thermal CSP (desert)
28 fossil gas in a CCGT
30 Coal
49 Hydro (medium sized dam)
75 Nuclear (in a PWR)
Source:[1]

Wikitable EROEI - energy sources in 2013 is not sourced. Does any of the nine citations in section Energy returned on energy invested#Low carbon power contain these figures? For now, a "citation needed"-tag is appropriate. -- Rfassbind (talk) 03:00, 1 November 2014 (UTC)

Table removed 04-Nov-2014. — Preceding unsigned comment added by 161.73.149.112 (talk) 10:56, 4 November 2014 (UTC)
The table was sourced in 1 Nov, with the reference in the article text right beside the table. For you two who are feigning the inability to find the reference supporting it, I put it right bang smack within the table for you PRIOR to its removal by the above IP user on 04-Nov-2014. Remove this again and I'll take 161.73.149.112 or whomever else to the dispute resolution board.
According to a transatlantic collaborative research study by 6 analysts led by D. Weißbach, and peer reviewed in a 2013 issue of the journal Energy, the uncorrected for their intermittency("unbuffered") EROEI for each energy source analyzed is as depicted in the attached table,[2][3] while the buffered(corrected for their intermittency) EROEI stated in the paper for all low carbon power sources, with the exception of nuclear and biomass, were yet lower still. As when corrected for their weather intermittency/"buffered", the EROEI figures for intermittent energy sources as stated in the paper is diminished - with the magnitude of the reduction of EROEI dependent on how reliant they are on back up energy sources.[4][5] -- 178.167.254.22 (talk) 08:10, 9 November 2014 (UTC)
Here's the PDF of the mentioned Weißbach-publication (archived). This publication has been openly criticized for its methodology. The EROEI figures for solar PV can be found on page 13 and 14. It says that the result corresponds to an energy payback time (EPBT) of six years. In addition, the publication by D. Weißbach et al. also claims that the results are "all in good agreement" with other cited studies. However, these studies are 6 to 14 years old and most likely outdated. When reading the PV-section of the study, one clearly gets the impression, the author held strong opinions about photovoltaics even before selecting the data and designing the methodology for his calculation.
Less controversial sources do not agree with an EPBT-figure of six years. Both, a NREL publication from the year 2004 and a recent Fraunhofer ISE Photovoltaics Report (see page 30) show much lower figures.
In response to the above statement by an unregistered user: note, that it is good practice to add a citation to a wikitable, especially when the section contains many citations, and that may eventually get removed when the text is being edited. Finally the (quote) "Remove this again and I'll take 161.73.149.112 or whomever else to the dispute resolution board." sounds very strange to me... -- Rfassbind (talk) 05:33, 13 November 2014 (UTC)
The publications authors, responded to all the nonsense criticism leveled at them in the Journal of Energy* as you well know as I included that claptrap in the article prior to your reverts. Secondly Rfassbind from your talk page and edit history one gets the impression that it is in fact YOU who hold "strong opinions about photovoltaic[s]" and not the trans-Atlantic team of scientists. Therefore I do not consider you to be an unbiased editor on this topic, considering your devotion to your favorite energy source. Thirdly, despite your filibustering, the EROI of ~3 for solar "PV in GERMANY" found in the peer-reviewed D. Weißbach et al paper, is perfectly in line with the most up to date figure expounded by IEEE researchers in 2014, that the EROEI of solar photovoltaic(PV) electricity is likely in the range 2.2 to 8.8.[6]
Here is the "criticism"* you brought up which I will include here for interested readers. I edited the article to include this "criticism" as a courtesy for those of you who believe that solar PV has EROEIs as high as conventional fossil fuels etc, this belief was expertly dispelled by D. Weißbach et al.
Although the methodological integrity of this paper was called into questioned by, Marco Raugei, in late 2013.[7] The authors of the initial paper responded to each of Raugei's concerns in 2014, and after analysis, each of Raugei's concerns were summarized as "not scientifically justified" and based on faulty EROEI understandings due to "politically motivated energy evaluations".[8] In 2012, a non-peer reviewed analysis of solar PV by Vasilis Fthenakis of Brookhaven National Laboratory, states that the EROEI is 60 for thin film solar in the USA Southwest based on First Solar's 11.9% efficient panels in 2009.[9] In 2012, Fthenakis co-authored another paper with the previously mentioned, Marco Raugei, which states that solar photovoltaic EROEI matches that of fossil fuels.[10]
As I conveyed to you all earlier, if this peer-reviewed paper and its table are removed again. I will be forced to bring this to the dispute resolution board. I await their reply.
178.167.254.22 (talk) 00:05, 16 November 2014 (UTC)
For the record, the original paper by Weißbach et. al, as well as their later reply piece [1], have been rebutted again, this time by a transatlantic team of reputable researchers led by Dr. M. Raugei, and peer reviewed in a 2015 issue of the journal Energy [2]. — Preceding unsigned comment added by 161.73.149.112 (talk) 10:41, 20 January 2015 (UTC)


Here is a direct link to the dispute resolution board. This is an interesting discussion and the topic (EROEI) is important. ––Nikolas Ojala (talk) 02:43, 17 November 2014 (UTC)
As I state in my detailed defense of the Weißbach et. al paper at the above linked dispute board, the - IP 161.73.149.112 who in bold acknowledges deleting the Weißbach section, is in all probability Marco Raugei, as their IP when geolocated is from the very same "university" he gets paid by. Raugei would clearly have a high degree of vested interest in keeping out of the popular domain, that is wikipedia, a paper by his opponents and that his "criticism" of the Weißbach et al paper resulted in the Weißbach team expertly responding, and putting his "criticism" to bed over 6 months ago.[3]
Marco Raugei is based in Oxford Brookes University UK (not to be confused with the real Oxford Uni). The above IP 161.73.149.112 user, who you can geolocate as from, you guessed it folks - Oxford Brookes University, first came in and essentially stated in the third person that the Weißbach paper is still "subject to scientific controversy" on 2 Oct 2014(a deceitful but not fatal move, as Raugei himself was responsible for stoking up most of the faux "controversy" about Weißbach et. al in the 1st place) but then for some reason Marco Raugei(our mystery IP user) came back over a month later on Nov 4 2014 and deleted the entire section on Weißbach!
Here's a third party source that corroborates that the team headed by Weißbach, expertly put down Raugei's attempt to criticize their paper So it's not just me who thinks so.


As you can imagine, this is a bit of a revelation, and I think further investigation by a wikipedia administrator is in order, particular to see if Rfassbind knew the IP user was Raugei WP:SOCK /sock puppet-ing.
178.167.254.22 (talk) 13:29, 21 November 2014 (UTC)

The dispute resolution at the WP:DRN has been closed (archive) with the following rationale (quote) "After 16 days no DRN volunteer has accepted the case and not even the filing party has participated in several days." I hope this very disturbing interaction is now over. Please let me know on my talkpage in case the disputed content is reintroduced to the article. Thx & cheers, -- Rfassbind (talk) 01:13, 2 December 2014 (UTC)

The dispute resolution board may have failed in its duties but that does not mean that this clear case of conflict of interest(WP:COI) is by any means over. The recent IP editors* of this article page have again, exclusively promoted Marco Raugei related publications. Having analyzed their editing style, one determines it is still Raugei doing the editing. All he has done, after I outed him here earlier, is switch to using proxy IP's in Japan and the US. So not only is it WP:COI it is WP:SOCK.
An admin seriously needs to get involved in this farce.
Regardless what is the truth about conflict of interest and sockpuppetry, if you bring this case back to the Dispute Resolution Board, I would suggest to concentrate in the essential question. The other questions may be resolved after that. ——Nikolas Ojala (talk) 13:02, 4 December 2014 (UTC)
What a total joke that Raugei's vandalism - censoring his peers and then self-promotional advertisements, have been allowed to stay in the article as long as they have.
178.167.149.15 (talk) 00:39, 4 December 2014 (UTC)

Technicality

I have been working on some additions to this article for a wikipedia college course and was thinking about changing the introduction slightly. I have just done a research project on this topic and I think how it is introduced could be simpler for a person who might not know much about the energy subject area. A lot of the article is very technical and hard to digest for a person who might not have heard of EROEI before. I don't want to step on any toes but am trying to keep the technical integrity while also making the information more accessible. The rank of this article on http://www.readabilityofwikipedia.com suggests that it is harder to read than 66% of wikipedia articles. AmsNU2015 (talk) 14:18, 17 November 2015 (UTC)

Be bold! If you know how to make the article essentially better, be convinced that it must be done. However if you are still unsure, just show the improved introduction right here, and we may discuss about it. It is good that at least some editors care about readability of articles. ——Nikolas Ojala (talk) 21:10, 17 November 2015 (UTC)
Thanks for the encouragement! I added a section (called additional EROEI calculations), added a few sources and tried my best to reconfigure some trickily worded sentences. Through doing this though I saw that the low carbon power section seems like a summary of a scientific article. The information is beyond my comprehension but if anybody knows what that section is talking about it would be fantastic if they could synthisize it to be more like an encyclopedia article and less of a summary of the article's findings. AmsNU2015 (talk) 14:56, 23 November 2015 (UTC)

Hello fellow Wikipedians,

I have just modified one external link on Energy returned on energy invested. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at {{Sourcecheck}}).

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 09:43, 24 December 2016 (UTC)

Hello fellow Wikipedians,

I have just modified 2 external links on Energy returned on energy invested. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

  • If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
  • If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 03:03, 21 September 2017 (UTC)

  1. ^ "Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants. Energy Volume 52, 1 April 2013, Pages 210–221".
  2. ^ "Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants. Energy Volume 52, 1 April 2013, Pages 210–221".
  3. ^ Dailykos - GETTING TO ZERO: Is renewable energy economically viable? by Keith Pickering MON JUL 08, 2013 AT 04:30 AM PDT.
  4. ^ "Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants. Energy Volume 52, 1 April 2013, Pages 210–221".
  5. ^ Dailykos - GETTING TO ZERO: Is renewable energy economically viable? by Keith Pickering MON JUL 08, 2013 AT 04:30 AM PDT.
  6. ^ "Energy return on energy invested (eroi): a quintessential but possibly inadequate metric for sustainability in a solar-powered world?. Proceedings of IEEE Volume 102, Issue 8, 18 July 2014, Pages 1118–1122".
  7. ^ "Comments on "Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants"—Making clear of quite some confusion. Energy Volume 59, 15 September 2013, Pages 781–782".
  8. ^ "Reply on "Comments on 'Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants' – Making clear of quite some confusion" DOI: 10.1016/j.energy.2014.02.026".
  9. ^ "PV ENERGY ROI Tracks Efficiency Gains, by By Vasilis Fthenakis of Brookhaven National Laboratory, Solar Today 24 June 2012" (PDF).
  10. ^ "The energy return on energy investment (EROI) of photovoltaics: Methodology and comparisons with fossil fuel life cycles, Marco Raugei, Pere Fullana-i-Palmer, Vasilis Fthenakis, Energy Policy Volume 45, June 2012, Pages 576–582".