Sunday, February 14, 2016

Nothing but net

Good time Charlie ' s
Got the blues
      - Danny O'Keefe
Will he ever return?
     -Kingston Trio (Charlie on the MTA)
      I was unable to attend Charles Hall's presentation at Linfield.   Happily the presentation was taped and is available  here.    Dr Hall is no doubt familiar to you all.   He essentially created a new field of energy analysis, that of net energy, or EROI.        
         His presentation was designed for the undergraduates in attendance, and therefore provides a nice primer, for anyone unfamiliar with the field.   I found it interesting on a number of levels.   First,  I found it quite amusing when he took  a few pokes at Portland ' s claim to be a "sustainable" city, noting the large number of automobiles .  The city obviously consumes a great deal of energy,   but how much does it produce?  Where does it get its food?
   ( Speaking of food , here are some interesting items.  A recent study finds that Portland could survive on what could be grown within 50 miles.   But its a different story when you look at what is actually grown.  see here and here
"Our research team found out that currently, the agricultural production in the highly fertile Willamette Valley does not meet the dietary needs of the local inhabitants for not only staples such as grains and oils but any of the USDA’s six food groups: grains, vegetables, fruits, dairy, meat and beans, and oils.
In 2008, Willamette Valley agriculture production yields would not have been able to feed the local population in any of the USDA food categories. If the population had tried to eat local foods it would only have been able to meet 67 percent of the annual grains requirement, 10 percent of vegetable needs, 24 percent of fruits, 59 percent of dairy, 58 percent of meat and beans, and none of the dietary oil requirements.
Beyond not satisfying the needs of local markets, much of the valley’s harvest is exported. While the region’s local food culture is being promoted and demand is increasing, its growth depends partly on readily available, locally grown staples.")
      Back to Dr Hall
       If I were to summarize the talk, I would say the main focus was on diminishing returns, which is to say the fact that we have already exploited the easiest and cheapest resources.   We are now exploiting more difficult and more expensive resources, - that is resources with a lower Energy Return on Energy Invested (EROI).   "Less bang for the buck" has implications for investment in energy production.  See here,  and Dr David Murphy's paper , (The implications of declining energy return on investment of oil production"
       It also has implications for society at large.   We have gotten so used to high EROI fuels, to the point that we have been able to ignore that fact that energy actually costs energy.  Its been so cheap that we have been able to treat it as free.    Hall argues that our current economic models basically ignore energy altogether, when in reality energy is the key, the "sine qua non", of all life, of the biosphere, and of the economic system of which it is a subset.
       But we will no longer have the luxury, of ignoring energy costs, and EROI.  For instance. climate change is an energy problem.  Our current energy system is poisoning the biosphere.  The obvious solution is to move to wind and solar.   But, wind and solar have lower EROI than coal, and oil.  (If they had a higher EROI, we would have moved to them already).   How low?   It is hard to come up with a hard EROI number for wind and solar.  For one things, they are quite variable depending on where you site the facility, and how many prime locations there are.  Hall's own study of a solar facility in Spain, concludes that this facility only has an EROI of 2.5:1.  see this summary and review of his book.  (In this article, 45 studies are reviewed finding a mean value of 10:1 for solar ; and 18:1 for wind)   .  If one includes any storage needed to address intermittency, these numbers could be reduced by half or more.  See here.  
       These numbers are very inexact, but they give us an idea of what the future holds.  More energy will be required to produce the energy we use.  And there will be less energy left over for all the other things that society has grown to expect - agriculture, transportation, recreational shopping and opera.  :>).   According to Hall, in order to have all that stuff , society's  energy system must have a EROI of 14:1
      Hall doesn't actually address it, but there is one more aspect that is even more tricky.   How do we get to this new renewable energy system.    What does it take for a system to reproduce itself?   How fast can we get there?
      Here is an interesting study for energy planners : Deriving an Improved Dynamic EROI to Provide Better Information for Energy Planners, by two authors, one from the Argonne Labs, the other the World Bank.   They note that EROI provides a metric which measures energy over the life of the project.  They note in order to model the build out of wind and solar,  the timing of when the energy is spent, and when it is produced also needs to be taken into account.     Wind and solar are "front loaded",  most of the energy expended occurs in year one, while output is over 20-30 years.  They try to model the what it would look like for a windmill to provide energy for society, while it also "saved up" enough energy to produce another windmill.  They find, it could not produce the "next" windmill until close to end of its life - 28 years -  making a rapid "grow out" of renewable power (from renewable power) a very iffy proposition.   see also an interesting series of posts 
      This issue is similar to Dr. Tom Murphy's idea of a "Energy Trap" .   He imagines a world with declining fossil resources, and thus each year, less and less fossil energy is available to society.  (An alternative scenario might be a society that decides it wants to reduce its carbon output, and therefore agrees to a declining use of fossil energy)   Society decides to engage in a rapid build out of wind and solar.  But the build out itself consumes energy, and the energy cost is relatively high, because the costs of wind and solar are "front loaded" .  He notes that during the build out period, society must get by on less and less energy, something that is politically unlikely.
"Many of us have great hopes for our energy future that involve a transition to a gleaming renewable energy infrastructure, but we need to realize that we face a serious bottleneck in its implementation. The up-front energy investment in renewable energy infrastructures has not been visible as a hurdle thus far, as we have had surplus energy to invest (and smartly, at that; if only we had started in earnest earlier!). Against a backdrop of energy decline—which I feel will be the only motivator strong enough to make us serious about a replacement path—we may find ourselves paralyzed by the Trap.

"In the parallel world of economics, an energy decline likely spells deep recession. The substantial financial investment needed to carry out an energy replacement crash program will be hard to scrape together in tough times, especially given that we are unlikely to converge on the “right” solution into which we sink our bucks.

Politically, the Energy Trap is a killer. In my lifetime, I have not witnessed in our political system the adult behavior that would be needed to buckle down for a long-term goal involving short-term sacrifice.

It's not easy delivering bad news.  The rest of us have a tendency to "shoot the messenger".  Here is another energy transition blogger, noting that problem  from here

 I’ll state my position as clearly as I can here: an interest in critically assessing the capacity for renewable energy systems to directly substitute for incumbent energy systems should not be conflated with “being opposed to renewable energy”. I myself am a long-time proponent for and supporter of a transition to renewably-powered societies. Having taken the time to be fairly broadly and deeply informed in this area, it is apparent that there are significant uncertainties relating to the forms that such societies might take, especially given the tight coupling between current globally-dominant societal forms, and the characteristics of their primary energy sources. It’s apparent to me that humanity stands a better chance of developing future societies supportive of high life quality if these uncertainties are taken seriously, rather than being discounted or ignored. The question that most interests me here is:
What forms might future renewably-powered societies take, if they are to enable humans and other life forms to live well together?
And following from this, how might we best pursue the process of transition towards such future societies? 
Good questions

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