Monday, March 3, 2014

Letter to Pedro A. Prieto for the Energy Resources Yahoo Group (including Denis Frith and Kermit Schlansker)

Hello Pedro,  (attention Denis and Kermit)

You wrote: “One of the most striking discoveries of this study was to realize that about 2/3 of the energy inputs were due to factors other than those usually considered in the conventional EROI or EPBT analyses that we gave for good at about 8-9:1”.

I want to be absolutely certain that “two-thirds of the energy inputs [measured in BTUs rather than counted like items in a list] were due to factors other than those usually considered in the conventional EROI or EPBT analyses” [that amount to about one-eighth or one-ninth of the total energy produced by the solar installation under investigation]. 

Perhaps, I had better mention to you the criticism of EROI (ERoEI) by Denis Frith in this forum.   I am interested in what your response might have been.  I know I have been critical of you and Charlie in the past; but, I have been defending all of us in an on-going debate with Denis who completely denies the usefulness of net energy measurements.  Here is my draft of a post I will try to finish speedily because of the late hour:

Denis again makes himself useful with the following comment:  (By the way, Kermit, notice that our on-going “debate” does have useful consequences.) 

As usual, Tom has an unfounded belief in recycling of materials. He does not take into account the fact that when the time comes to replace the system the supply of materials will be greatly depleted. He claims that it would not be a problem for a thousand years! He, of course, ignores the impact of friction because it spoils his delusion. He again says I am wrong yet he quotes ERoEI* >1 after saying if First Solar can capture the solar energy without hurting wild life. That is a provision not included in ERoEI*. [italics mine]  He leaves out consideration of other practical factors such as the fertile soil that is not longer able to be used for food production.

So now we have had another rant of Tom with his fallacious comments. I still look forward to sound comments from some one.

Denis

[Note added to this blog:  Notice that Denis begs the question routinely.  I don't think he knows this is a logical fallacy.]

----- Original Message -----
From: twayburn@att.net
Sent: 02/25/14 03:55 AM
To: energyresources@yahoogroups.com
Subject: Re: [energyresources] Solar Fall-out

I, too, think that First Solar should find a way to capture solar energy without hurting wildlife; but, if they had already managed to do this; and, if they had a process with ERoEI* <http://eroei.blogspot.com/> greater than 1.0, then Denis's comment would be wrong and extremely harmful. If ERoEI* were greater than 1.0, First Solar would have found a way to rebuild their installation repeatedly with only a very small stockpile of materials that could be replenished with part of the net energy returned. They could take care of Denis's other objections as well. Of course, they would begin operations with a large deficit because much of the energy cost of building the installation must be paid before a single BTU is returned; therefore, the problems would be at the beginning - not during maintenance or when it comes time to replace the aging installation. The materials of construction do not disappear with age except in such small amounts as to be unimportant for the first thousand years. They must find someone who will lend them energy to get started with. This initial loan could be paid back with interest.

Tom Wayburn, BS chemical engineering, MS mathematics, PhD chemical engineering


I need to state specifically how ERoEI* takes care of wildlife.  From http://eroei.blogspot.com/ :   

An energy technology is sustainable if and only if ERoEI* (E-R-O-E-I star) is no less than 1.0.  An entire society is sustainable if and only if the compound ERoEI* of its entire mix of energy technologies is no less than 1.0.   Early on, recognizing that a community can persist for quite a long time if most of the characteristics of ERoEI* are satisfied, we considered quasi-sustainability; that is, during a transition period between fossil fuels and renewable energy, we must tolerate some slight environmental destruction and diminution of our storehouses of essential natural resources because of the large proportion of the energy investment for most renewable energy technologies that must be paid before any energy is returned.

I think it might be useful to define "feasibility" as something different from sustainability.  For example, we might say that a renewable energy is feasible if no more characteristics of ERoEI* are relaxed than are consistent with the community standards and laws of the land currently.


Early on, I defined sustainability in terms of the phase space for the Earth: “When all is sustainable, the phase-space trajectory of the environment will be required to be periodic and close to the expected natural trajectory, that is, the trajectory we might expect without human influence. Moreover, the steady state of our population and our economy must be matched by the steady state of our storehouses of natural resources” [by which I mean the “natural resources that the process uses”.]   The requirement of periodicity is perhaps inappropriate.

However, the second of the three notes that precedes the thought experiment by which the principal energy inputs are defined [http://eroei.net/eroeistar.htm] states:

·        The price of energy should reflect the cost of preventing or repairing any changes to the environment that diminish the quality of life of mankind and other species or that compromise the sustainability of the relevant ecosystems including the magnitude of the storehouses of natural resources.  The quality of life depends upon aesthetics as well as pure material circumstances.

I have no idea what would make this clearer.


The methodology I favor accounts for most externalities by adding the computed energy cost of preventing undesirable and ensuring desirable outcomes.  For example, the incremental energy cost of building a solar installation so that animals in its environment are not harmed is added to the EI (energy-invested) term.  Since ERoEI pertains to the delivery of energy when and where it is wanted, the ratio for a location remote from the energy production facility under investigation has its EI incremented by the cost of the infrastructure necessary to so deliver it; and, if the delivery of the energy is delayed, the cost of delivering the most suitable substitute energy product is added to the EI term (while taking appropriate credit for it in the ER term).

Best regards to you and Charlie – I am counting on you.

P.S.  I have not discussed at least two of Denis's objections.  (If you can get past his insults and his habit of begging the question - in this case by referring to my comments as "fallaceous", which would be the conclusion of a valid argument to determine which of us is correct rather than the beginning of a new argument, Denis's objections are useful.)  


1.  Preserving and using soil nutrients:  Suppose the installation  is to be installed on a concrete pad.   The preparations for the foundation of the pad should include shoveling the soil to appropriate garden spots in and among the portions of the plant site borrowed by the technology.  This is consistent with multiple uses of the site for solar power, a garden, and a wildlife refuge.  

2.  Friction does not generally remove much material but whatever is removed can be filtered from used lubricants before the lubricants themselves are recycled.  This is a stationary solar collector; therefore, the recycling is particularly easy, as the cooperation of consumers is unnecessary except with respect to that part of the delivery mechanism that enters the user's space.  One way in which technological progress could manifest itself in a steady-state or shrinking economy is by permitting each successive generation of solar collection equipment to harvest the same net energy with less massive equipment thus reducing the amount that needs to be recovered somewhat, say from 99% to only 95%, provided the losses are not otherwise harmful.  Remember, unlike energy efficiency which is bounded away from 100% by the hard Carnot limit, material recovery can be as close to 100% as we are willing to expend the energy for. 

As in all the previous cases, even if the process does not realize sustainability, ERoEI* should be computed as though it did; that is, by adding the computed cost of doing these things to the energy-invested term.

No comments :

Post a Comment