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crossposted from Voices on the Square

In the online support for the April, 2013 Scientific American article on Energy Return on Investment (EROI), Scientific American online interviewed Charles Hall, developer of the EROI concept, on whether Fossil Fuels will be able to maintain economic growth. In one of his answers, Charles Hall responds to the question:

What happens when the EROI gets too low? What’s achievable at different EROIs?
He says:
If you've got an EROI of 1.1:1, you can pump the oil out of the ground and look at it. If you've got 1.2:1, you can refine it and look at it. At 1.3:1, you can move it to where you want it and look at it. We looked at the minimum EROI you need to drive a truck, and you need at least 3:1 at the wellhead. Now, if you want to put anything in the truck, like grain, you need to have an EROI of 5:1. And that includes the depreciation for the truck. But if you want to include the depreciation for the truck driver and the oil worker and the farmer, then you've got to support the families. And then you need an EROI of 7:1. And if you want education, you need 8:1 or 9:1. And if you want health care, you need 10:1 or 11:1.

Civilization requires a substantial energy return on investment. You can't do it on some kind of crummy fuel like corn-based ethanol [with an EROI of around 1:1].

A big problem we have facing the alternatives is they're all so low EROI. We'd all like to go toward renewable fuels, but it's not going to be easy at all. And it may be impossible. We may not be able to sustain our civilization on these alternative fuels. I hope we can, but we've got to deal with it realistically.

Energy Return on Investment versus Net Energy Yield


When looking at EROI, it is easy to get lost in the woods of arguing whether an EROI is 50 or 30, whether something is left out that should be included, whether something is included that should be left out. However, an important point is raised in an 2011 Oil Drum article, The Energy Return on Investment Threshold, which begins with the statement:

Hall and Day (2009) report that the EROI for coal might be as high as 80 and that for hydropower, EROI is 40. Does this mean that coal is twice as ‘good’ as hydro? The answer is no ...
Don't worry about the next paragraph if you aren't comfortable with algebra, as you will see, the problem has already been worked out for you.

How could 80 fail to be twice as good as 40? Well, EROI looks at energy out for each one energy input used up. That uses the amount of energy you lose along the way as the measuring stick, when for a lot of issues, that's the thing we want to measure. To give a useful measure of how much energy is used up in producing the energy, you need the concept of net energy. Net Energy is measured in absolute units (Watts, Joules, etc), but you can also take it as a percentage of the energy produced, to give the Net Energy Yield:

  • EROI = Energy Out / Energy In
  • Net Energy = Energy Out - Energy In
  • Net Energy Yield = (Energy Out - Energy In) / Energy Out
  • So: Net Energy Yield = (EROI-1)/EROI

And the figure on the right plots the EROI versus the Net Energy Yield (which it calls the "% Energy Out"). And that is why an EROI of 80 is not twice as good as an EROI of 40. The Net Energy Yield comparison for EROI of 80 vs 40 are yields of 98.75% vs 97.5% (79/80 vs 39/40), so the same energy flow results in 1.25% less energy available.

Its when we get down to the level marked on the figure as the EROI threshold that the differences start to buy. Instead of comparing EROI 80 vs EROI 40, what happens when we compare EROI 8 vs EROI 4? That is 87.5% vs 75%, a loss of 12.5% less energy available. Indeed, lets look at the Net Energy Yield for the hypothetical values in Charles Hall answer (EROI ~ Net Energy Yield %)

  • 1.1 ~ 9%
  • 1.2 ~ 17%
  • 1.3 ~ 23%
  • 3 ~ 67%
  • 5 ~ 80%
  • 7 ~ 86%
  • 8 or 9 ~ 88%-89%

Indeed, he sets the threshold for a modern industrial society with the long childhood education required for a highly skilled workforce at just about the same point that David Murphy places the threshold for the "cliff" when drops in EROI start to really bite into our available Net Energy Yield.


What are the Sustainable, Renewable Net Energy Yields Available?

Just as the Big Oil funded Heritage, Cato and Reason foundations churn out reports on why providing Americans with any freedom of choice to pick an alternative to gasoline fueled cars and diesel fueled buses is a bad thing ~ since they are self-identified libertarians, and nothing says "liberty" like denying Americans choice ~ there seems to be a cottage industry in pushing the idea that a fully sustainable, renewable energy economy is an impossibility. Google for "Can the World Run on Renewable Energy" and "negative case" and you'll find several different revisions and country-specific versions of one of these arguments.

However, when we consider available resources and the EROI threshold of 8, the negative case is on shaky ground.

First and foremost comes wind power. In a meta-study of wind power EROI studies from 1997-2007, Kubiszewski, Cleveland and Endres (2009) find an average over 60 operational studies of 19.8, for a net energy yield of 95%. And this will, of course, rise over the coming decade, since advances are still being made in the energy efficiency of wind turbines at relatively low wind-speeds. Clean Technica covered a press event by General Electric last month introducing its newest model wind turbine. According to GE Wind Products General Manager Keith Longtin:

“We’ve made incredible gains since acquiring the property,” Longtin stated, pointing out that today’s GE turbines are operating at close to 98% availability (97.6%), the same as a thermal coal plant. Furthermore, he continued, “with the introduction of the 1.6-100, we’ve also improved the capacity factor (a measure of energy efficiency) from 35% ten years ago to over 50% today.” Over 50% capacity factor is far above the capacity factor that most people think of when they think of wind turbines. Clearly, very significant strides have been made to get to such a high percentage.

Contributing to the boost in turbine availability and efficiency, GE’s Brilliant 1.6-100 captures and converts more wind energy at lower (Class 3) wind speeds, which, by definition, blow at 7.5 meters per second (m/s).

The 1.6-100 integrates short term grid scale battery power storage. About 7% of wind power currently available to installed wind turbines is lost because of the fact that the grid cannot accept power increases from wind turbines as rapidly as the wind turbines can provide the power, and with short term grid scale battery power, that ramp up of power availability can be matched to the grid bottleneck. The batteries play a similar role when ramping down the wind turbines. It makes sense to integrate this scale of battery storage with the wind turbines, since they can use the power transformer that the wind turbines require in any event.

Kubiszewski, Cleveland and Endres (2009) also cite meta-studies of EROI estimates for other power sources. Notable among them are:

  • Photo-Voltaic Solar with an average EROI of 6.7, though primarily from simulation studies rather than operational studies;
  • nuclear with an average EROI of 15.8-9.1, depending on whether studies that omit the energy cost of one or more stage of fuel processing are included;
  • and dammed hydropower with an EROI of 12, though as noted with limits to our ability to increase dammed hydropower

They do not include estimates of corn ethanol fuel, singled out by Charles Hall as an example of a fuel with an egregiously inadequate EROI. The basis for his remarks can be seen in David Murphy, Charles Hall and Bobby Powers (2011), which considers EROI studies of corn ethanol fuel, ranging from estimates of EROI of 0.8-1.5. We don't really need to wade into the details of their average estimate of 1.01 (a net energy yield of 1%), since an optimistic EROI of 1.5 is a Net Energy Yield of only 33%.

It is important to distinguish corn ethanol from sugar cane ethanol. Corn ethanol requires substantial energy-intensive fertilizer inputs to get maximum yield for a plant creating a protein-intensive cereal grain, with so much of the plant discarded in the production of corn ethanol. Indeed, a major part of the difference between low EROI at the top end and extremely low estimates at the bottom end are whether the cogeneration of byproducts of corn ethanol biomass is counted, or whether the byproducts are treated as a product that must be returned to the field to sustain fertility.

The other extreme of a liquid biofuel that is often cited is sugar cane ethanol, with a plant that is specialized to produce a relatively large amount of simple carbohydrates, and which can grow and regrow two to three times per planting. An EROI figure of 8 for Brazilian sugarcane ethanol is often cited, but as Robert Rapier notes in the 2008 Oil Drum EROI round-up, this is a specialized figure focusing just on oil independence:

The oft-cited Brazilian EROEI is really a cousin of EROEI. What is done to arrive at the 8 to 1 sugarcane EROEI is that they only count the fossil fuel inputs as energy. Boilers are powered by burning bagasse, but this energy input is not counted. (Also, electricity is sometimes exported, and credit is taken for this). For a true EROEI calculation, all energy inputs should be counted. So what we may see is that the EROEI for sugarcane is 2 to 1 (hypothetically) but since most inputs are not fossil-fuel based the EROEI based only on fossil-fuel inputs is 8 to 1.
An EROI of 2 is still substantially better than an EROI of (optimistically) 1.5 for corn ethanol, since that is an energy yield of 50% rather than an energy yield of 33%. However, it still relegate currently produced ethanol to the status of a secondary fuel source for specialized applications where the portability of a liquid fuel justifies reliance on such a low EROI fuel.

The most promising biomass energy source that is proven technology (though not currently widely deployed) is biocoal. As Engineer-Poet wrote in 2006, in a long article worth setting aside time to read from beginning to end:

... [A] whale of a lot of energy is lost in conversions.  The average refinery makes gasoline with 83% efficiency, but engines are so inefficient that more energy goes to refining losses than pushing the vehicle.  An ethanol engine is potentially more efficient than the gasoline equivalent, but the conversion from biomass to ethanol loses so much that it takes more biomass energy than crude oil to do the same job!  Biomass gasification may be more efficient than Iogen's hydrolization and fermentation, but even a 70%-efficient process yields barely 18% end-to-end efficiency at best.  Still, the available energy from biomass looks to be several times the energy we actually use from crude oil.  The conclusions are inescapable:
  1. There is sufficient biomass energy to replace motor fuel and then some... if the energy is not wasted.
  2. Using bio-ethanol in piston engines means taking between 4/5 and 9/10 of the captured energy and throwing it away.
  3. Even burning biomass as a replacement for e.g. coal in conventional powerplants means 60% losses or more.
  4. It looks impossible to grow enough biomass to take that path.
  5. The old paradigm won't work any more.  A new systems approach is required.
  6. The essence of a successful system will be fewer conversions and minimizing losses.
Engineer-Poet's solution to reducing conversions and minimizing losses is biocoal: charcoal produced through partial burning in a sealed chamber that allows capturing the exhaust gases. The sealed chamber is the biggest difference between old-fashioned charcoal and biocoal production, since the exhaust gases can be used directly generate electricity. Assume that:
  • ...
  • 53.5% of the energy is yielded as charcoal (30% by weight).
  • 88% of the remainder is yielded as chemical energy in hot gas (11.1 quads gas + 1.51 quads reaction heat + recycled heat).
  • The gas can be converted to electricity at 50% efficiency.
Then the charcoal and the medium-BTU thermal gas has a crude energy loss of 12% of 47.5%, or 5,7%, so those products have an energy yield of 94.3%, and an EROI of 17.5. This is the figure that is directly equivalent to the EROI for creating various liquid biofuels.

Now, if all of this is converted to electricity, the EROI and energy yield is lower. The net energy yield for electricity is much lower if the biocoal is burned in conventional coal powered plants at an efficiency of about 33%, while the medium-BTU is converted into electricity at the production site using Solid Oxide fuel cells at an efficiency of 50%, then the electrical net energy yield is 38% (18%+20%), or an EROI of 1.6, However, if the biocoal is converted into electricity using Direct Carbon Fuel Cells with an efficiency of about 75%, then the electrical net energy yield is 60% (40%+20%), or an EROI for the electricity of 2.5.

Of course, the wind power and photovoltaic solar power is created as electricity, so do not suffer the energy losses when converting solid and liquid fuels to electricity. At the other extreme, any thermal power plant that burned a coal or sugarcane ethanol fuel would operate at a negative net energy yield, acting as a net consumer of energy rather than as an energy source.

Current nuclear technologies are primarily Light Water reactors consuming uranium fuel without recycling. We have on the order of 70 years of usable uranium fuel sources at current rates of consumption, and as we work through our richest uranium fuel sources, the EROI and net energy yield of existing Light Water technology will continue to decline as the energy input for fuel enrichment continues to climb. (Note that a recent diary on EROI at daily kos citing nuclear EROI of 75 from a paywalled study, appears to be a case of either rigging the study by ignoring fuel enrichment energy costs, or else based on simulations of hypothetical nuclear technologies under development.)

There are technologies that recycle fuel using side-effects of the nuclear chain reaction, to substantially reduce the energy cost of fuel enrichment, and these may offer EROI of 15 to 25 over a longer period of time, but most of these technologies carry a risk of nuclear proliferation. However, the thorium fuel cycle, which was not been pursued intensively in the United State precisely because it is less useful than many rivals in the generation of weapons-grade nuclear materials, does offer a prospective recycling fuel cycle that might well offer useful supplementary source of electrical power.


EROI of a Sustainable Energy Portfolio

The first main element that matters for the maintenance of an advanced industrial economy is not the EROI and Net Energy Yield of specific components of the energy portfolio, but the overall EROI and Net Energy Yield of the total portfolio of energy sources.

It has been noted that the US could move to 20% windpower without requiring substantial changes in the way that we manage and regulate electricity generation. All that would be required would be some investment in long distance electricity transport from the Great Plains to population centers east of the Mississippi. No substantial investment in energy storage would be required, since shuffling around the operation of existing hydropower and existing gas-fueled peak power plants would cope with the volatility of wind power.

This could be used to argue that "we can use at most 20% windpower for our electrical needs", but that would be assuming that we are incapable of adapting our electrical supply system to cope with new types of power sources. That is a shaky assumption, since after all we were not handed our current system full-formed from some extra-terrestrial civilization, but rather developed it to cope with the capacities and limitations of fuel-powered electricity supplies.

More importantly, though, this ignores portfolio effects. Solar power and windpower generation tend to peak at different times of the day, and the peak of solar power generation is well correlated to peak power demand. So 30% wind with 10% solar is easier to integrate into the grid than 20% wind alone. At the same time, for both, high production periods at a specific wind farm or solar producing region tends to be correlated with lower production in the other technology, and with wind farms and solar producing regions in other areas.

So the 20% "wind power threshold" based on integration of a specific wind resource into a specific grid interconnect can be reasonably projected to a 40% wind plus 20% solar threshold for a broadly distributed set of wind and solar power resources ... plus 40% of "something else.

Assume that half of that "something else" is catering to specialized needs where EROI gives way to other factors, for which I'll give an EROI of 1 and a net energy yield of 0%, and 20% of biocoal and biocoal production electrical generation (and note that the generation of power as a by-product of charcoal production can be scheduled to coincide with peak demand periods), at an EROI of 2.

What would be the end result? 40% (wind) of energy consumed in energy production has an EROI of 19, 20% (solar PV) has an EROI of 5.7, 20% (biocoal biomass) has an EROI of 2, and 20% (specialized/portable power sources) have an EROI of 1. That is a weighted average of 13.42, or a  net energy yield of 92%, comfortably above the net energy cliff.


The Transport Challenge

However, this presents the US transport system with a substantial challenge.

To the extent that we can efficiently transport things using electricity, we know that it will be feasible to transport them using sustainable renewable power. And if the electrically powered transport can be done with a sufficient efficiency gain, we can pursue electrical transport and the development of sustainable electrical power sources in parallel, since the electrically powered transport automatically inherits any improvements to the sustainability of the electric power grid as they occur. By contrast, most fueled transport require some form of conversion to shift from an unsustainable to a sustainable power source.

Local electrical passenger transport and Active Transport alternatives include walking, cycling, ebikes, neighborhood electric vehicles, electric freeway-capable cars, trolleybuses, light rail and heavy rail. Many of these have local freight delivery versions, including freight cycles, neighborhood electric delivery vehicles, and electric conventional vans and light trucks, while a trolleybus, light rail or heavy rail corridor could also be used for local freight. Given advances in battery technology, an electric truck operating along a trolleybus route and departing from it to complete its trip on the public right of way could be readily integrated into a trolleybus corridor system.

Further, whatever our supply of high energy density liquid fuel may be, we can prioritize local freight shipments and allocate a given budget of low-EROI liquid fuels to performing those tasks.

However, if we consider the alternatives for long distance freight transport, to provide the 1,000mile+ freight movements that our economy relies upon, the list of alternatives drops away. Air freight and long distance highway freight consume large amounts of high energy density liquid fuels, using energy-intensive means of transport, and production of those fuels from sustainable energy sources imposes substantial energy losses from the conversion.

Long distance electric freight rail does not discriminate between unsustainable and sustainable sources of electricity, and we have ample sustainable electricity sources to support electric freight rail.

My version of the Steel Interstate proposal extends this to also operate the Steel Interstate electric freight rail system as Electricity Superhighways. This provides an essential complement to wind and solar power since, as already discussed, an ability to draw on wind and solar power from multiple regions results in a more stable total supply of renewable energy, and substantially eases the task of integrating wind and solar power into the grid.


A Transport Revolution

Where the Steel Interstate is most revolutionary, however, is in its efficiency.

The "energy cliff" argument of Charles Hall revolves around how much net energy yield we require to operate a modern industrial economy. This is a substantially different thing from the "energy cliff" argument of David Murphy, that observes an EROI threshold of about 8, where it becomes critical to be aware of the EROI of our energy sources.

David Murphy's threshold is simply arithmetic, and as such it does not in fact tell us what Net Energy Yield we need to maintain our industrial economy.

And Charles Hall's argument is surely correct regarding some level of Net Energy Yield, what level we need to maintain our industrial society surely depends on whether we rely on efficient or inefficient ways to do what we need to do.

And it is here where the Steel Interstate promises efficiency gains compared to are present reckless waste that are substantial enough to be called revolutionary. Long distance rail freight is substantially more efficient than diesel truck freight, even with the same diesel fuel source. And long distance electric rail freight is substantially more efficient than diesel rail freight. When the two efficiencies are combined, electric freight rail, consumes less than 10% as much energy per ton-mile as long distance diesel truck freight.

If we were to compare electric rail freight powered by sustainable electricity with an average EROI of 13 to long distance diesel truck freight, that would be equivalent to a oil with an EROI of over 130 ...

... while the large oil fields discovered before the 1960's with EROI in the range of 80-100, the sustainable electric power with an EROI of 13 is effectively more abundant for the task at hand than the big oil fields of West Texas and Saudi Arabia.

And those big oil fields are increasingly exhausted, with petroleum EROI falling toward 20 and sure to continue to fall.

That's what I call the Steel Interstate Energy Revolution.


Conversations, Considerations and Contemplates

As always, rather looking for some overarching conclusion, I now open the floor to the comments of those reading.

If you have an issue on some other area of sustainable transport or sustainable energy production, please feel free to start a new main comment. To avoid confusion among those who might be tempted to yell "off topic!", feel free to use the shorthand "NT:" in the subject line when introducing this kind of new topic.

And if you have a topic in sustainable transport or energy that you want me to take a look at in the coming month, be sure to include that as well.

Originally posted to Voices on the Square on Sun Jul 21, 2013 at 06:00 PM PDT.

Also republished by Sunday Train, Climate Hawks, Systems Thinking, Thorium - Better Nuclear Energy, and Community Spotlight.

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Comment Preferences

  •  I'm still reading. (9+ / 0-)

    Some of this is rather dense and I don't follow all of it (not being an energy scientist). One thing I can't help but wonder about is how we could change our system that evolved in a time of cheap energy to be more commensurate with a time of dear energy. Could we, for example, reconfigure in such a way as to not rely upon 1,000mile+ freight movements? Maybe rethink the way we ship goods, produce food, etc? Maybe learn to scale back, localize functions as much as possible, be more strategic?

    However, if we consider the alternatives for long distance freight transport, to provide the 1,000mile+ freight movements that our economy relies upon, the list of alternatives drops away. Air freight and long distance highway freight consume large amounts of high energy density liquid fuels, using energy-intensive means of transport, and production of those fuels from sustainable energy sources imposes substantial energy losses from the conversion.
    •  As an institutional economist, ... (17+ / 0-)

      ... the question has to be asked which is the more wrenching change ... to provide $4b in ongoing interest subsidy to establish 30,000 miles of electrified Rapid Freight rail and Electricity Superhighways ...

      ... or eliminate reliance on long distance transport and convert our national economy back into the collection of loosely connected regional economies of the early 1800's?

      I reckon that the latter is the more wrenching change.

      The more wrenching change is the one that will inspire the fiercer resistance from a wider range of existing vested interests.

      Now, I don't believe in silver bullets, so I'm down with pursuing that as well, but I think the Steel Interstate system is an approach that offers greater opportunities to make substantial progress in the medium term.

      Support Lesbian Creative Works with Yuri anime and manga from ALC Publishing

      by BruceMcF on Sun Jul 21, 2013 at 08:06:21 PM PDT

      [ Parent ]

      •  That's a fine point. (6+ / 0-)

        I certainly see the value of electrified Rapid Freight rail and Electricity Superhighways.

      •  given that combustion, of whatever fuel, (2+ / 0-)
        Recommended by:
        BruceMcF, PeterHug

        yields carbon into the atmosphere, then should not one goal be to eliminate combustion itself as an energy conversion process, if all the carbon can't be retained?

        So is the "Steel Interstate" of electric trains also the  right-of-way for long-distance transmission lines beyond what the train needs?  New DC grid legs?

        OPOL isn't suggesting a return to the 1800s in distribution/production so much as gently suggesting that consumers be nurtured towards simply wanting less.  Like we don't have enough stuff?  Habits of consumption have to change, which are generational-scale shifts of the philosophical paradigm.  Efforts in this direction will yield positive results easier than struggling to keep up with runaway mindless unsustainable demand with better and better tech.

        ("easier" isn't the right word.  Energy expended in efforts to change people's consciousness is not wasted, but it's hard to quantify.)

        Great diary, BTW.

        don't always believe what you think

        by claude on Mon Jul 22, 2013 at 04:51:02 PM PDT

        [ Parent ]

        •  If the combustion is carbon ... (3+ / 0-)
          Recommended by:
          Zinman, claude, PeterHug

          ... that was taken from the atmosphere in the previous year, its not a net addition of carbon to the atmosphere. So rather than the goal being to eliminate combustion itself, the goal would be to eliminate combustion of fossil fuels to the extent that we can.

          The Steel Interstate is not only the right of way, the support stanchions for the overhead electric are also the support for the UHVDC lines. Its the double purpose use of the support stanchions that makes it effective take a slightly more roundabout route for the UHVDC lines of rail corridors versus the very straight line routes of conventional UHVAC or UHVDC transmission corridors.

          And saying "gentle nurtured to wanting less" does not make it any less of a wrenching change. I welcome any progress made on that dimension, but I am not willing to gamble the ability of the US to maintain a national industrial economy for the balance of this century entirely on the progress made along those lines.

          Support Lesbian Creative Works with Yuri anime and manga from ALC Publishing

          by BruceMcF on Mon Jul 22, 2013 at 05:31:44 PM PDT

          [ Parent ]

          •  I dunno, Americans seem to be (0+ / 0-)

            rolling with the punch.  I'm surprised there's not more dissent to this new "normal" we seem to be stuck in.

            No question, I like living in an advanced high-tech civilization. but I find that about 90% of its products I find useless.  The other 10 % are priceless.

            Go figure.

            I do appreciate your pointing out the distinction between fossil energy and using carbon that is already on the table.

            So the advantages of DC "super-transmission"  overcome the vagaries of RR rights-of-way.  I guess most RR trackage is fairly straight,  but where I am what I see is mountain twisty and I wondered if that was an issue.

            But, to belabor the point,  the issues aren't lack of tech, but of lack of political will to subsidize these kinds of improvements; still comes down to re-educating the populace who vote for the politicians who stand in the way of sane policies.

            don't always believe what you think

            by claude on Mon Jul 22, 2013 at 11:19:45 PM PDT

            [ Parent ]

  •  Thanks for some great reading (4+ / 0-)
    Recommended by:
    BruceMcF, FishOutofWater, barath, Odysseus

    I expect you might have read posts by kossack Barath who I was about to say is not very active but then it turns out posted today, on a non-energy topic.

    I'll have to read more carefully to make an intelligent comment, so much content here.

    •  Yes, and I am indeed a supporter ... (5+ / 0-)

      ... of the Clean Energy Dividend.

      Support Lesbian Creative Works with Yuri anime and manga from ALC Publishing

      by BruceMcF on Sun Jul 21, 2013 at 08:40:01 PM PDT

      [ Parent ]

      •  Thanks for posting this Bruce (5+ / 0-)

        It was great to see an explanation of EROI on Daily Kos.  It's a topic few have heard of but is of great importance given the current reckless pursuit of fossil energy at any cost in the form of hard-to-extract, low-EROI fuels like tar sands, shale gas/oil, ultra-deepwater oil, arctic oil, etc.

        Doesn't Germany use mostly electric freight trains these days?  I remember some (or many?) European countries do this already, and it's worked out quite well for them.

        Do you think there's any way to expand such electric freight rail at the local/state level first, in the absence of any national policy?  I wonder how we can get such a project started.

        contraposition.org - thoughts on energy, the environment, and society.

        by barath on Mon Jul 22, 2013 at 06:45:35 AM PDT

        [ Parent ]

        •  Germany uses some ... (4+ / 0-)
          Recommended by:
          Odysseus, BYw, barath, Zinman

          ... many European countries do, as there are many electrified corridors that are primarily passenger corridors also used for freight, and if the electric overhead supply is there, it is normally more cost effective to make use of it.

          its Switzerland that makes the heaviest use of electric freight rail, because of their terrain which makes the superior performance of electric trains on higher gradient corridors (eg, 1:40 or 2.5% versus a more common US 1:100 or 1% gradient) an appealing feature.

          Support Lesbian Creative Works with Yuri anime and manga from ALC Publishing

          by BruceMcF on Mon Jul 22, 2013 at 10:37:13 AM PDT

          [ Parent ]

          •  Just for curiosity, how does Spain match up? (1+ / 0-)
            Recommended by:
            BruceMcF

            I know they have invested in passenger rail, so perhaps also in freight system improvements.  And Spain is the second most mountainous country in Europe, after Switzerland. Seems they would have similar challenges of grade, and efficiencies that electrification could provide.

            I'm part of the "bedwetting bunch of website Democrat base people (DKos)." - Rush Limbaugh, 10/16/2012 Torture is Wrong! We live near W so you don't have to. Send love.

            by tom 47 on Mon Jul 22, 2013 at 12:08:00 PM PDT

            [ Parent ]

            •  I don't know, but I know who to ask. (0+ / 0-)

              He's living in Spain, and I don't know if he checks his twitter in the evenings, but I'll ask him.

              Support Lesbian Creative Works with Yuri anime and manga from ALC Publishing

              by BruceMcF on Mon Jul 22, 2013 at 12:12:37 PM PDT

              [ Parent ]

            •  The big difference between Switzerland ... (0+ / 0-)

              ... and Spain is that Spain relies much more heavily on diesel road freight than Switzerland ... this article (Spanish) claims 95.6% of freight movements (I do not know if that is by ton-mile or by value).

              I am not sure whether they are saying it is 80% electric rail freight or 20% (Google Translate sometimes bungles those kinds of comparisons), but it does stress that in the EU, compared to 4.1% rail (the 0.3% balance is probably waterborne), France is 15.9%, Germany 22.2%, Sweden 35.3%, Austria 37.4%.

              Another challenge in Spain is that they are undergoing a rail line privatization, and the new private companies seem to be focusing on diesel locomotives for the flexibility ... and given the uncertainty how which lines of freight business will be picked up by which private operator, that makes financial sense, but it threatens electric rail freight taking a step back in Spain even as the diesel freight trains increasingly run primarily under electric power supply.

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              by BruceMcF on Mon Jul 22, 2013 at 03:02:25 PM PDT

              [ Parent ]

  •  Thanks for explaining EROI & implications so well (6+ / 0-)
    Recommended by:
    barath, BruceMcF, eOz, thomask, BYw, Zinman

    This diary is an excellent reference on energy economics. This is a critically important topic that is poorly understood by world leaders.

    I'm really happy to see you posting here again.

    look for my eSci diary series Thursday evening.

    by FishOutofWater on Mon Jul 22, 2013 at 06:37:20 AM PDT

  •  Outstanding. Thank you. NT (1+ / 0-)
    Recommended by:
    BruceMcF

    "The true strength of our nation comes not from the might of our arms or the scale of our wealth, but from the enduring power of our ideals." - Barack Obama

    by HeyMikey on Mon Jul 22, 2013 at 07:57:12 AM PDT

  •  Thanks, very illuminating. (0+ / 0-)

    One error:  Your last equation should read

    Net Energy Yield = Energy Out * ((EROI-1)/EROI)
    Just a typo I'm sure, since the rest of your post seems to get the numbers right.

    “What’s the use of having developed a science well enough to make predictions if, in the end, all we’re willing to do is stand around and wait for them to come true?” - Sherwood Rowland

    by jrooth on Mon Jul 22, 2013 at 07:57:49 AM PDT

    •  No ... (2+ / 0-)
      Recommended by:
      jrooth, Zinman

      ... a Yield is a ratio (typically expressed as a percentage) ...

      Energy Out * ((EROI-1)÷(EROI)) is Net Energy itself, in energy units.

      The plot, however, is EROI versus "% energy out", which are two ratios. The latter is what I have dubbed Net Energy Yield

      (Net Energy) / (Energy Out)

      = {Energy Out * ((EROI-1)EROI)} Energy Out

      = (EROI-1)/EROI

      Or, alternatively, 1 - 1/EROI, but the first formulation is easier to do on the fly no a computer calculator.

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      by BruceMcF on Mon Jul 22, 2013 at 10:43:52 AM PDT

      [ Parent ]

      •  Ah, OK ... I misread. (1+ / 0-)
        Recommended by:
        BruceMcF

        As you say, I was thinking of net energy.

        “What’s the use of having developed a science well enough to make predictions if, in the end, all we’re willing to do is stand around and wait for them to come true?” - Sherwood Rowland

        by jrooth on Mon Jul 22, 2013 at 11:11:45 AM PDT

        [ Parent ]

        •  If you are familiar with ... (1+ / 0-)
          Recommended by:
          jrooth

          ... the work, its an easy misread to make, since David Murphy does not plot Net Energy itself, but Net Energy as a percent of Energy Out, and he does not name that percentage.

          I find that a lot of people find it easier to grasp percentage ratios than values in Watts and Joules, and to write up the Net Energy in terms of David Murphy's percentage value from his energy cliff plot, I had to give it a name.

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          by BruceMcF on Mon Jul 22, 2013 at 11:33:10 AM PDT

          [ Parent ]

  •  Nicely done, virtual tippenwreck / nm (1+ / 0-)
    Recommended by:
    BruceMcF

    “Vote for the party closest to you, but work for the movement you love.” ~ Thom Hartmann 6/12/13

    by ozsea1 on Mon Jul 22, 2013 at 08:10:04 AM PDT

  •  Thanks for this outstanding contribution. (2+ / 0-)
    Recommended by:
    BruceMcF, greengemini

       In this Age of Oil we've gotten used to having everything we want when we want it (just on time delivery) but in a previous age, the Age of Sail, wind transport was dominant and somewhat variable. Shipping commodities across the great plains by electric rail powered by windmills in the great plains is in some sense a return to transportation dominated by wind (40% of the mix). If we can accept some inconvenience when the wind isn't blowing or the sun isn't shining we might be able to go higher than 40/20 for wind/solar and get an even better net yield.
        In between the Age of Sail and the Age of Oil was a relatively brief Age of Steam. It is somewhat of a Steampunk fantasy but is there a path to integrate steam back into the mix?

  •  The diary you cited (1+ / 0-)
    Recommended by:
    Odysseus

    was mine, and I can assure you that:
    1. Contrary to your speculation, nuclear fuel enrichment costs were completely accounted for by the Weißbach study, as should have been clear from the diary text.
    2. Contrary to your speculation, the nuclear technology assessed was current light-water reactors, as should have been clear from the graph.

    As noted in the diary, EROI of nuclear has been a moving target over the past 20 years as the industry switches from gas diffusion enrichment to the 35-times-more-efficient centrifuge enrichment. Weißbach assumed 83% centrifuge, 17% diffusion which is about the current world average. (As also stated in the diary.) Once the changeover is complete (about 2017, according to the WNA), nuclear's EROI will come in at about 100.

    Since you're interested in EROI issues, I might also suggest that it would be worth your while to either buy the article, or head over to your nearest subscribing university library to get beyond the paywall.

    We are all in the same boat on a stormy sea, and we owe each other a terrible loyalty. -- G.K. Chesterton

    by Keith Pickering on Mon Jul 22, 2013 at 10:07:59 AM PDT

    •  The focus of the piece is on ... (2+ / 0-)
      Recommended by:
      Mindful Nature, Zinman

      ... currently developed sustainable renewable technologies, and Light Water once through fuel cycle power plants are not sustainable, renewable energy technologies, so I wouldn't have paid for the article for a side-note on a neighboring topic.

      In any event, since the meta-study by Harris R. Greenberg+, Clara Smith+, James A. Blink+, Massimiliano Fratoni++, William G. Halsey+, A.J. Simon+, and Mark Sutton+ 2012 finds a representative EROI(f) of 23.8, it seems that you are cherry picking an outlyer that is convenient for your preferred conclusion. Mode advocates do that a lot ... nuclear, wind, solar, geothermal, petroleum, natural gas - cherry picking is remarkably common among those advocating a particular mode and looking at policy challenges as another advocacy opportunity. So I may be especially sensitive to what appears to be cherry picking, given that I encounter that kind of mode advocacy in transport all the time.

      And given that Weißbach presumes that nuclear would require no storage of energy to meet peak demand, where an all-nuclear grid would have massive storage needs, while setting the storage requirement for wind at the needs of an all-wind-power electrical grid, I am skeptical that it is worth my money.

      Notes:
      + is Lawrence Livermore
      ++ is Penn State

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      by BruceMcF on Mon Jul 22, 2013 at 11:05:07 AM PDT

      [ Parent ]

      •  As long as you are over there (0+ / 0-)

        you can take a look at some of the issues behind the assumptions used in calculating the EROI for various renewable energy systems that are pretty unrepresentative of how such systems would actually operate.  

        Touch all that arises with a spirit of compassion. An activist seeks to change opinion.

        by Mindful Nature on Mon Jul 22, 2013 at 07:37:26 PM PDT

        [ Parent ]

        •  But that seems like it would be ... (0+ / 0-)

          ... doing exactly what I am trying to avoid.

          My conclusion in the article that a reasonable portfolio of sustainable renewable electrical energy sources is comfortably over the threshold is stronger if it is based on the balance of existing research.

          If I have to debate the existing EROI research to arrive at the same conclusion, that places me on much less secure ground.

          Obviously any meta-study results on EROI on Photo-Voltaic power will lag current technology. For a meta-study to collect a large enough sample, it must cover an appreciable period of time, and then if it is credible work, the meta-study itself takes time to complete the methodology comparisons and sensitivity analysis and then to get through refereeing to publication.

          So obviously the 6.7 EROI on PV electricity is low. It can't help being low, given the efficiency gains in developments over the past three years. Using an estimate known to be low strengthens my case, since I can't be charged with cherry-picking a number that suits my conclusion.

          And in any event, I can't see any of the stuff you call on me to look at as long as I am at Greenberg, Smith, Blink, Fratoni, Halsey, Simon+, and Sutton (2012), since its a nuclear EROI meta-study, not a PV, CSP, wind, dammed hydropower, or run of river hydropower EROI meta-study.

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          by BruceMcF on Mon Jul 22, 2013 at 08:23:45 PM PDT

          [ Parent ]

  •  I wouldn't completely write off ethanol (2+ / 0-)
    Recommended by:
    Odysseus, BruceMcF

    I admit I can't make a great case for it, but I think a case can be made that ethanol might make a better energy storage and transport medium than many of the alternatives that are currently available (e.g., existing battery technology.)

    If -- and it's a significant "if" -- all, or nearly all, of the energy required to grow, harvest, and convert feed stock into ethanol can be supplied from sun and wind power, then we have a process that converts variable and low-density energy sources into a constant and high-density energy storage medium. I'm not sure, but I suspect that as the price of fossil fuels rises, there will be a tipping point at which ethanol becomes worth another look for this reason.

    Let us all have the strength to see the humanity in our enemies, and the courage to let them see the humanity in ourselves.

    by Nowhere Man on Mon Jul 22, 2013 at 10:40:58 AM PDT

    •  Ammonia makes a better energy storage and ... (6+ / 0-)

      ... transport medium than ethanol, though to use it as a combustion fuel rather than to recover the stored energy as electricity with a fuel cell requires a primer fuel, since ammonia has already been shown to work as the primary fuel for a diesel engine but is not itself capable of starting a diesel engine. if provided with a starter fuel, biodiesel is a more appealing primer fuel in that application than ethanol.

      Given that photovoltaic cells harvest a much greater fraction of solar energy per square meter than photosynthesis, and there are promising ammonia from electricity via solid state technologies being developed ...

      ... and that we may need a sustainable source of ammonia in any event to maintain adequate food supplies during the coming climate chaos ...

      ... I find the ammonia fuel path far more promising than either corn ethanol or sugarcane ethanol.

      Indeed, one of our critical needs for fueled equipment is farm machinery, and something that existing diesels can be adapted to run is particularly appealing in the task of shifting farm machinery to a sustainable, renewable fuel.

      ~~~~~~~~~~~~~~

      Note that I only addressed the forms of ethanol currently in wide production. It may be that cellulosic ethanol will prove to be an effective motor vehicle fuel for some share of our total transport task, so I'd certainly support further research and development on cellulosic ethanol and long term ecologically sustainable production of cellulosic ethanol feedstocks ...

      ... but my focus in the article is on existing technology. If we can have an EROI 13 sustainable, renewable electrical grid with existing technologies, then technological progress from this point is a bonus, rather than an urgent necessity, and we can invest serious resources now in rolling out the elements of a transport system that can take advantage of a sustainable, renewable electrical grid.

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      by BruceMcF on Mon Jul 22, 2013 at 11:47:02 AM PDT

      [ Parent ]

      •  That was stranded wind's premise, (3+ / 0-)
        Recommended by:
        BruceMcF, Ignacio Magaloni, Zinman

        ammonia production from surplus wind energy on location out in wind country where they also farm, as an "energy storage" medium.

        SW is long gone,  but he did make that point quite effectively.

        don't always believe what you think

        by claude on Mon Jul 22, 2013 at 05:01:41 PM PDT

        [ Parent ]

        •  It was, indeed, Stranded Wind ... (2+ / 0-)
          Recommended by:
          Ignacio Magaloni, claude

          ... who first put me in touch with that research.

          Most passengers are within, to, or between the large metro areas. Most freight is within, to, or between the large metro areas. And electrifying transport within, to, and between large metro areas includes some long-established and proven technology.

          But farming by its nature is dispersed, and mechanized agriculture far harder to electrify than urban passenger and freight, regional passenger and freight, and interurban passenger and freight.

          And I am not one to put all our eggs in a single basket ~ while I would be very happy for us to dramatically increase the share of organic, locally sourced food in our food supply, I want to be sure that our current mechanical farming system keeps working until and unless the organic, locally sourced food supply demonstrates that its in a position to handle 100% of our needs.

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          by BruceMcF on Mon Jul 22, 2013 at 05:25:30 PM PDT

          [ Parent ]

          •  well yeah. I look at my own life, (1+ / 0-)
            Recommended by:
            BruceMcF

            like breakfast the other day, where I was thinking about how much of what we were enjoying in that moment we were able to produce here, in our valley,  which was a significant part, but where the fuck am I going to get olive oil if not from thousands of miles away?

            Once upon a time,  every City was surrounded by "truck farms" that supplied daily produce to its City, and that is still a viable model, as all sorts of productive fertile farmland was gobbled up to make Suburbia (far more "wealth" is created farming people in tidy suburbs than having people farming food on that land)  I give you the San Francisco Bay Area as a prime example.    That will be a touchy subject, as only well off elites will afford the extra (honest) cost of better quality local food and the poor will be stuck with WalMart produce that is still being brought in from 1000miles  away.

            This will takes some thoughtful transitioning.

            don't always believe what you think

            by claude on Mon Jul 22, 2013 at 10:52:02 PM PDT

            [ Parent ]

            •  And working to retain the option to ... (1+ / 0-)
              Recommended by:
              claude

              ... move things cross country does not mean we shouldn't pursue community gardens, as many communities in Cleveland are turning to ... sometimes to convert empty land with no residential property development demand in sight from what could be a community blight into a community benefit.

              No single week's entry in a series spanning multiple years is going to cover every dimension of an issue like this each week.

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              by BruceMcF on Mon Jul 22, 2013 at 11:18:21 PM PDT

              [ Parent ]

  •  Great diary. (2+ / 0-)
    Recommended by:
    BruceMcF, Zinman

    Much info, this is one I have printed to PDF so I can go over and over.

    You know, the concept of energy ROI is an excellent view.  Hadn't ever considered the ramifications.  But its good to see this, and will stimulate, I hope, some followup posts by some of the commentors (myself included)

    One thing I think I'll post is an analysis of the impact of developing a Fully Burdened Cost of Energy, which I will now call FuBCE (pronounced Foob-kee).  This takes into account the total overall cost, including what the intermediate and long term effects are on the world.  

    I suspect if this were developed and publicized it would lead to a lot different conclusions about what to do from here on out, and how quickly we must do it.  For the cost will rise astronomically (I think) if we do nothing.

    •  Yes, the Net Energy Yield is a critical ... (1+ / 0-)
      Recommended by:
      PrescottPatriot

      ... value for quite a lot of Full Economic Cost analyses (where "Economic" is far from equal to "Financial", despite the common confusion).

      After all, quite a lot of shifted and hidden costs are on the input side. So one energy source could have more impact in terms of gross energy output ... but if the alternative has a low enough EROI, A could well have a lower impact to get the same Net Energy.

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      by BruceMcF on Mon Jul 22, 2013 at 11:54:58 AM PDT

      [ Parent ]

      •  A lot of my recent experience (1+ / 0-)
        Recommended by:
        BruceMcF

        is working with military and government types.  Their focus is on energy security (availability) and cost is secondary.  They have fully burdened cost calcs, but only the supply end.  Some (in EPA and NASA for example) are looking further down the road, but its not something on their radar right now.  And it should be.

        I think developing an approach that incorporates all aspects of the cost, then develops comparisons and what-ifs, and shows the real cost of waiting (which is what we're doing right now).  If that were public knowledge, and fodder for pundits, the public would be screaming for solutions.  

        •  This is where STRACNET could be strategic ... (1+ / 0-)
          Recommended by:
          Ignacio Magaloni

          ... since it is part of their mission to consider strategic logistics, it is not a stretch for them to consider net energy as a logistical issue in assuring secure transport.

          But they would need a champion higher up the totem pole in the Pentagon.

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          by BruceMcF on Mon Jul 22, 2013 at 02:50:39 PM PDT

          [ Parent ]

  •  what is his evidence (0+ / 0-)

    for ANY of the thresholds he cites?

    As usual, the EROI seems to arbitrarily pull thresholds out of pure air that magically fall just above renewables and just below fossil fuels.

    Touch all that arises with a spirit of compassion. An activist seeks to change opinion.

    by Mindful Nature on Mon Jul 22, 2013 at 07:30:45 PM PDT

    •  In what sense is the EROI ... (1+ / 0-)
      Recommended by:
      Ignacio Magaloni

      ... magically above renewable and magically below fossil fuels?

      As I wrote, wind power so comfortably above the threshold that even as 40% of a portfolio with every other major component below that threshold, the total renewable, sustainable portfolio is comfortably above that threshold.

      Meanwhile, the EROI petroleum continues to fall inexorably toward the cliff, already dropping from the 100-80 range in the middle of the last century to the 30 range toward the end of the last century to the 20 range today, with absolutely no evidence nor reason to believe that the trend is going to turn.

      The claim that there is a threshold somewhere is a claim that implies we cannot bank on fossil fuels, since the EROI of fossil fuels can only fall. That is the nature of a heavily exploited non-renewable resource.

      That is, after the reason, why although I noted the difference between the arithmetic threshold and the economic threshold, and that the economic threshold is subject to being moved as a result of efficiency gains:

      And Charles Hall's argument is surely correct regarding some level of Net Energy Yield, what level we need to maintain our industrial society surely depends on whether we rely on efficient or inefficient ways to do what we need to do.
      As far as ethanol, that's not something that would really concern anyone concerned with sustainable, renewable energy, since turning even more of middle American farmland into a corn monoculture, extending the Gulf dead zone, and slash and burning still more Brazilian rainforest for ethanol sugarcane plantations are not ecologically sustainable solutions, and the economy is a wholly contained subset of the ecosystem, so if something is ecologically unsustainable, it is economically unsustainable by definition.

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      by BruceMcF on Mon Jul 22, 2013 at 08:12:28 PM PDT

      [ Parent ]

    •  Be a little skeptical of EROI. It's a useful tool (2+ / 0-)
      Recommended by:
      Ignacio Magaloni, BruceMcF

      for certain types of calculations, but it doesn't tell the whole story. In particular, the idea that you've got to have a certain fairly high EROI "threshold" to maintain "civilization" seems a bit dubious. Most current energy systems are bloated and inefficient. It takes twice as much energy in the US to make one dollar of economic output as it does in Japan. With better energy efficiency, conservation, and grid management, we could use cleaner but less EROI dense fuels, which would also be more sustainable.

      As an analogy, imagine much of the world's energy systems (I'm looking at you, China) as 2,000 pound couch potatoes. They are accustomed to eating very energy dense food, like sugar megapuffs. If you start running out of megapuffs, the couch potatoes...err energy industry...will tell you civilization will collapse without more megapuffs. But, in reality, they need to slim down and eat healthier food. The new food may not be packed with as many calories as megapuffs, but it also doesn't cause as many negative side effects, like obesity, diabetes, heart disease, etc.

      So, I think a lot more studies need to be done before I'd accept some of these EROI threshold numbers. One thing I feel supremely confident about is that full cost accounting on the externalized costs of many high EROI fuels has not been done. When you consider some of the real costs of these high EROI fuels, it may be worth it to have fuels that have lower EROI, but are much cleaner, safer, and more reliable.

      Just doing my part to piss off right wing nuts, one smart ass comment at a time.

      by tekno2600 on Mon Jul 22, 2013 at 08:13:45 PM PDT

      [ Parent ]

      •  I believe that I wrote ... (0+ / 0-)
        David Murphy's threshold is simply arithmetic, and as such it does not in fact tell us what Net Energy Yield we need to maintain our industrial economy.

        And Charles Hall's argument is surely correct regarding some level of Net Energy Yield, what level we need to maintain our industrial society surely depends on whether we rely on efficient or inefficient ways to do what we need to do.

        I do not see where in that statement anybody can say that I am taking Charle's Hall specific threshold numbers as some kind of natural law.

        Indeed, the statement means exactly the same as:

        As an analogy, imagine much of the world's energy systems (I'm looking at you, China) as 2,000 pound couch potatoes. They are accustomed to eating very energy dense food, like sugar megapuffs. If you start running out of megapuffs, the couch potatoes...err energy industry...will tell you civilization will collapse without more megapuffs. But, in reality, they need to slim down and eat healthier food.
        ... so it seems to me that you are telling me that instead of making an argument that I did not make, I should make the argument that I actually did make.

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        by BruceMcF on Mon Jul 22, 2013 at 09:10:14 PM PDT

        [ Parent ]

        •  Relax, buddy. You said a million things in your (0+ / 0-)

          book-long diary...and, yes, you did not neglect to talk about efficiency or hedge about on what exact "thresholds" may exist. My point is that I'm not so sure any of these simplistic calculations are really that accurate, or if thresholds are good ways of thinking about energy sector planning, other than to reach some very general conclusions. Many essential parts of power systems have always been energy negative (pumped storage, batteries, etc.). But, talking about thresholds misses the point in many of these cases. They provide a certain quality of power, they provide it at the right time, right place, and often prevent emissions from being generated in the wrong places and at the wrong times. The most useful thing I think you can get out of EROI is to prove that there are in fact enough energy alternatives out there to keep meeting reasonable energy needs in the near future, even as fossil fuels get to be increasingly expensive and unacceptable for the pollution they generate. That much is clear and can be show with a number of different calculations. But, big efficiency gains--and by big, I mean 2X, 3X and above--are necessary and possible across many parts of the energy and transportation sector. So, talking about our energy needs now or specific thresholds may lead us to the same kind of erroneous conclusions that so many studies have come to in the past about the expected growth of energy demand.

          Just doing my part to piss off right wing nuts, one smart ass comment at a time.

          by tekno2600 on Tue Jul 23, 2013 at 11:04:50 AM PDT

          [ Parent ]

          •  But that is why ... (0+ / 0-)

            ... the reason for looking at the EROI of the individual components is not to pick the components based on some EROI race, but rather as part of the process of building the porfolio.

            Building a renewable energy portfolio is a different kind of system building than putting together the parts of a fossil fueled electrical power system, and what matters for economic sustainability is the overall EROI of a total portfolio that

            We know because of strong EROI of Wind and because of the functional complementarity between Wind and Solar that any drop in weighted average EROI from Wind and Solar together it well worth it in terms of the benefit of integrating more wind into the grid.

            As far as the role of storage, I have of course written on that multiple times over the years in this series, and I'll surely come around to it again sooner rather than later.

            And there is still the second lesson to be drawn from EROI, which is that as we exhaust the high EROI petroleum sources and new sources coming online are far lower EROI petroleum sources, the total EROI of the petroleum supply system is only going to decline over the coming decades.

            As far as "big efficiency gains", I think that 10x efficiency gain shifting freight from long distance diesel motor freight to long distance electric rail freight qualifies. Just putting that out there.

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            by BruceMcF on Tue Jul 23, 2013 at 01:19:48 PM PDT

            [ Parent ]

          •  And while you can tl;dr ... (0+ / 0-)

            ... if you want, its a mere 3500 words, more or less, which is still short story range. You need to hit around 40,000 words for a novel.

            If someone was commenting without bothering to read the whole diary, they would normally say something like, "I haven't had a chance to read the whole thing, but have you addressed the issue of ... ?"

            Since, obviously, if you comment without reading the diary and don't flag that fact, the comment reads as if you are saying that I didn't raise that point. And if I thought  that the point was the central point underneath the entire argument, say, I would want to know whether it was because I had not said it clearly enough.
             

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            by BruceMcF on Wed Jul 24, 2013 at 08:49:45 PM PDT

            [ Parent ]

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