Talk:Embodied energy

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[edit] Major Editing

There seems to be many different types of embodied energy analysis, each of which has contributed to the developmental history of the subject. I have tried to give a brief overview of some of the differences. I have also included a new separate entry for the Emergy concept with associated links Sholto Maud 04:39, 26 November 2005 (UTC)

[edit] Bias

I could not help but notice the heavy-handed bias in the discussion about embodied energy in building materials, specifically about straw bales. I won't make arguments here, but would suggest that instead of using negative language in regards to a specific material, that be replaced by wording along the lines of "the scope of the energy used in the manufacture of the materials is difficult to determine, often allowing for wide ranges in embodied energy values for a given material." Andrew Netherton, 15:02, 28 February 2006 (UTC)

Hi Andrew. I've tried to clear up the article a little. How does it read now? Sholto Maud 21:36, 2 March 2006 (UTC)
Hello Sholto - It reads much more neutrally now. Thank you. Andrew Netherton, 22 March 2006

[edit] Comprehension Level

I'm finding that a major problem of Wikipedia is what level of assumed comprehension is appropriate? I argue that the subject matter of this article is one of the more important current concepts that is getting increasing airplay in the media, which will no doubt prompt more and more people to "wikipedia" Embodied energy. Many will read the first and second paragraphs and be content, but those who read on for a deeper understanding may find the text somewhat challenging to comprehend. I'm of the second type. I really WANT to understand, but learned almost nothing from the descriptions of the 3 current methodologies. Can they be written more concisely, clearly, or elegantly? I don't know, but you experts who wrote this please try. Who knows, the environment may even indirectly benefit from your efforts! (by Takeitupalevel)

[edit] NPOV

I added the NPOV tag because significant criticisms of the entire concept of embodied energy are not reported in the article. See Talk:Emergy#Neutrality. Flying Jazz (talk) 17:11, 17 November 2007 (UTC)

Could you be more specific? I (tried to) read the discussion you've pointed to, but I couldn't find anything in there criticising the basic proposition that trying to figure out how much energy goes into the making of something mightn't be a useful exercise.Lordrosemount (talk) 13:57, 18 March 2008 (UTC)

[edit] Embodied Energy in Energy

The proposed wide use of hydrogen as the medium in an energy transport, storage and recovery process (the "hydrogen economy") presents an opportunity to consider the energy embodied in an energy medium -- first in its generation (say, by the use of electricity and the electrolysis process), then in its compression for storage/transport and finally in its utilization. When used as a combustible fuel, the conversion yields either mechanical energy or electrical energy, but when converted in a fuel cell, the product is limited to electricity.

Apparently none of these processes -- electricity to electricity -- is very efficient at this time, representing a serious handicap to the "hydrogen economy" concept. That is, there is too much embodied energy in hydrogen energy transport, storage and recovery. . —Preceding unsigned comment added by 208.63.237.3 (talk) 05:03, 9 March 2008 (UTC)

[edit] Practical applications

I've noticed that the approach taken in this article is highly theoretical and, as Takeitupalevel notes above, largely impenetrable to the lay reader beyond the lead paragraphs. For professional reasons I came to this page looking for information about how the concept of embodied energy might have been, or be being, applied in the real world - whether any companies or pressure groups, for example, have attempted to use it as part of an effort to figure out the ecological impact of a specific product, as a supplement or alternative to carbon footprint or food miles calculations. Does anyone know anything about this that they could add, to make the article more useful for a general readership? Lordrosemount (talk) 14:02, 18 March 2008 (UTC)


[edit] References

The following text recently added needs references & citations before it can be put back into the main article. Sholto Maud (talk) 01:26, 20 May 2008 (UTC)

Embodied energy simplified

Embodied energy is the amount of energy needed to make a product. Embodied energy (ee) could be written as:

ee = Energy of manufacture + Transport energy raw materials to factory

But some life cycle analysts argue that true embodied energy should include the energy used in transporting goods from factory to site, energy needed to build the factory and machinery, energy needed to transport workers to the factory, energy needed to build the roads and so on. This could be written:

ee = Energy manufacture + Transport raw materials to factory + Transport of goods from factory to site + Energy to build and run factory + Energy to transport workers to factory + Infrastructure, roads, medical care, education (the list is endless)

Embodied energy is used to assess how environmentally friendly the product is, based on the assumption that less embodied energy is better for the environment. However it is possible that a product which takes a lot of energy to create might still save more energy throughout its lifetime. This could be written as:

Ecofriendly ee <= (is less than or equal to) Energy saved annually x Years product lasts

The reuse of reclaimed building materials could be considered to save the embodied energy of a comparative new product. This could be written thus:

Energy savings of reuse = ee of comparative new product

Many products contain a combination of new materials added to recycled materials which require less energy to process. For example, steel containing new and recycled steel would have a lower embodied energy than new steel. One list gives new steel as 38GJ/t, recycled steel as 10GJ/t, and has construction steel with a 60 per cent recycled content averaging 20GJ/t.

Hi Sholto, I am new to this. I think I understand the points you make about citations in my text but why are there none in the opening paragraph with the definition which seems contentious? 'Embodied energy refers to the quantity of energy required to manufacture, and supply to the point of use, a product, material or service.' The embodied energy that I deal with allows for inclusion of transport energy to take raw materials to the factory, but transport from the gate to site is usually added separately afterwards. Thornton Kay 21 May 2008. —Preceding unsigned comment added by Tkay (talk • contribs) 00:08, 21 May 2008 (UTC)


Hi Thornton.
  • Typically an article's opening paragraph is like an abstract and gives a definition and includes any notable aspects of the topic which are expanded on later in the body. Citations are then given in the body. (As with peer review articles, there are many examples where this is not the case, including articles that I have myself contributed). Perhaps the most important protocol for Wikipedia is that Encyclopedic content must be verifiable. For an article to be verifiable the body of the article should have citations to peer review literature. (Again various Wikipeida articles do not always follow this protocol, however the general view seems to be that their quality is diminished as a result).
  • As for the definition of embodied energy. As far as I understand it there seems to be a number of unresolved questions about where to locate the system boundary for one's calculations. Different theories of embodied energy locate the system boundary differently, resulting in a different methodology. Specification of the system boundary is an important part in identifying the root definition influencing one's choice of embodied energy methodology.
  • I think your contribution is good, and if you can put in some citations and references should go back into the main article as an example of one embodied energy methodology. Sholto Maud (talk) 03:23, 21 May 2008 (UTC)