Tom Konrad on cellulosic electricity 14

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1. 

   Sean Casten Posted 9:11 am
   24 Jan 2008

   CommentsMy biggest comment is that I agree with your assertion that this is a false dichotomy. Partly because we need clean fuels for power and transportation, so why choose one, but also because it is an academic question - I rather doubt that there is any magic lever one can pull which preferentially shifts resources from cellulosic ethanol to bio-power.  
   That said, I do have a few material quibbles:
   
   
   DOE projections of biomass potential are hugely variable, if not downright unreliable.  The problem is not one of incompetence, but simply because it's a really hard question.  As the question from a supply side (how much do we have?) and you get one, relatively low answer.  Ask it from a demand side (how much would we have if we were willing to pay $X/ton?) and you get another, much bigger answer.  (Oak Ridge has done a rather detailed, county-by-county analysis of this measure).  But even those analyses then raise questions as to what would happen if you could earn a given price for biomass.  For example, if you assume that biomass is worth $40/ton, you find that a lot of marginal land could be profitably harvested.  But then you have to ask whether farmers would rather dedicate their time to $40/ton woody biomass or $3.50/bushel corn, which gets into complicated questions of yields and farm economics.  I don't necessarily argue that one of these analytical methodologies is better than another, except to point out that there are certain, plausibly done studies that show that we need not be supply limited as you suggest.
   Cellulosic ethanol is fully synergistic with bio-power, and really inseparable therefrom.  Unlike corn, cellulosic feedstocks are lignin rich, and therefore supply all the fuel they need to run the plant and even export power to the grid.  Thus, where a corn-ethanol plant consumes significant amounts of natural gas and electric power, a cellulosic ethanol plant needs no additional fuel and exports power to the grid.  The precise benefit is obviously a function of the specific biomass and technology selection, but is fairly universal.  These power plants are pure cogen, way more efficient than the paltry 33 - 37% efficiency you get from co-firing with coal and give cellulosic ethanol a totally different (e.g., better) carbon signature than corn ethanol.  Remember that to build a CHP plant, you need a local use for the thermal energy.  And a cellulosic ethanol plant is a big thermal energy user.  Thus, for the same reason that there are so many CHP plants in paper mills, cellulosic ethanol plants - admittedly, once the technical kinks are ironed out - will be huge hosts for CHP plants.
   Finally, I think you understate the infrastructure shift required to go to electric vehicles.  Taking all the politics out of ethanol, it is by far the cheapest alternative fuel as far as infrastructure is concerned.  Plug in hybrids require less infastructure shift than EVs, but it's still significant.  Realistically, I find it far more likely that we would see a slow increase in ethanol content in our fuel (cellulosic and otherwise) and a concurrent increase in the deployment of fuel-flexible hybrids and plug in hybrids than that we would go to a 100% PHEV world with biomass cofiring.
   
   

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2. 

   GreyFlcn Posted 10:59 am
   24 Jan 2008

   Front-End versus Back-EndTaking all the politics out of ethanol, it is by far the cheapest alternative fuel as far as infrastructure is concerned.
   Says who?
   The frontend infrastructure cost of the cars would be smaller, yes. But thats only a small portion of the total required infrastructure for biofuels.
   But the backend infrastructure cost of everything else would be much larger with biofuels.
   Fertilizers, Growing, Harvesting, Shipping, Processing, Shipping, and Distribution.  And yes, the cars themselves.  And the maintanence.
   _
   With electric cars, 1. You replace the car. 2. You add a bit more coal or natural gas to existing power plants.
   
   http://greyfalcon.net/plugins4
   
   3. As for replacing the power plants themselves, we have to do that ANYWAYS.  Or else we aren't going to be winning this carbon fight.
   
   And likely they will be cheaper than new coal or nukes ANYWAYS.
   Then you have to factor in that the biofuels themselves ain't coming cheap.
   
   http://greyfalcon.net/oregon
   
   http://greyfalcon.net/biotaxes.png
   
   http://greyfalcon.net/biotaxes2.png
   
   http://greyfalcon.net/oilvsethanol2.png
   Then add to the maintanence of that biofuels infrastructure.  As compared electric power plant infrastructure would be overlapping and largely done ANYWAYS.
   Then add in the relative maintanence of conventional cars with ethanol, compared to series plugin hybrids. Thats a HUGE difference in private and societal infrastructure costs.

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3. 

   GreyFlcn Posted 11:20 am
   24 Jan 2008

   The other thing to considerAs long as we're talking about infrastructure.
   Is that batteries tend to have an exponential drop in price based on production volume.
   http://greyfalcon.net/batterycost.png

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4. 

   Biodiversivist Posted 2:21 pm
   24 Jan 2008

   I'm glad to see this posteven though Tom's point has been made a hundred times on this blog. See URGE2. Burning grass in a coal plant would displace far more CO2 than turning it into a liquid fuel and burning it in cars with 18% efficient ICE engines.
   As for switching cars to hybrid drives, I don't see the problem. We retool every single year for every single car model. Once the industry adjusts to hybrid drive trains they will become ubiquitous the way front wheel drive did.
   If somebody finally comes up with a biofuel that isn't worse overall than fossil fuels, fine.  But, until that happens, all you have are investors getting rich off of government mandates, and tax breaks that exist thanks to special interest lobbying.
   
   In the end, it all comes down to biodiversity. Poison Darts--Protecting the biodiversity of our world

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5. 

   JohnMashey Posted 2:55 pm
   24 Jan 2008

   Exponentially?In the chart you showed, I assume you used "exponential" colloquially to mean "the price drops a lot", which it does, at least from 10 to 100 to 1000.
   The chart showed does not show a mathematical exponential drop in price with volume.  It doesn't even show a linear drop with volume, especially with the log scale.
   That's OK, especially if that AFS Trinity design that Joe Romm reviewed works as well as it looks, all of which looks good for EV/PHEV fleets.
   But, it's not the equivalent of Moore's Law, where the cost/transistor has decreased exponentially [but more due to lithography than just unit volume.]
   An interesting comparison curve would be the charts on page 10 & 16 of Applied Materials' (AMAT) nice presentation:
   http://www.appliedmaterials.com/investors/assets/Solar_La ...
   that's ~straight line on a log-log scale, i.e., module cost has been decreasing linearly with increasing volume, i.e., cost ~ 1/volume, althouhg that won't keep up forever.
   Note that AMAT is a serious, conservative firm, not a startup touting futures, and I've heard their top guy in Solar (Charlie Gay) talk, and he seems pretty good.
   
   -John Mashey

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6. 

   Tom Konrad Posted 3:43 pm
   24 Jan 2008

   Biopower or Cellulosic EthanolSean, thanks for your thoughtful comment.  
   You're right, my assertion that "there isn't enough biomass" is an oversimplification.  Yet, no matter how much biomass there is, it is destined to become a valuable resource.  Given a valuable resource, the invisible hand of economics will push that resource towards the most effective use, which is biopower.
   Transport costs and heterogenous feedstocks will send some biomass to various uses.  For instance, Citrus Power's cellulosic ethanol from orange rinds seems like an efficient use of this relatively high quality feedstock.
   I also agree that cellulosic ethanol will probably provide more transportation energy than electricity in the short term, but I expect the electricity share to grow quickly in the medium term, which, as an investor, makes cellulosic companies much less appealing.
   As for your point of biopower/cellulosic ethanol synergies, I'll need to think about it some more... it does seem a good use of waste heat where there is no other industrila use.  On the other hand, the distributed nature of the feedstock means that in many cases even small uses of heat, such as rural schools and hosipitals, may be sufficient heat loads.
   On the infrastructure shift to electricity for transport, it is formidable, but then so is the shift required to get ethanol to market... this will probably be decided in the political realm: the fuel with the most subsidies will win.  Sad but, likely, true.

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7. 

   Pangolin Posted 7:27 pm
   24 Jan 2008

   Pyrolisis beats combustion.I'm going to sing this one note again and point out that pyrolisis of cellulosic feedstocks has many long-term advantages over straight combustion.
   Pyrolisis offers the ability to produce bio-oils, methanol, captured nitrates, produce bio-char, hydrogen, methane and heat. Of all these valuable products the bio-char, hydrogen and nitrates matter the most. Nitrate fertilizers (ammonia) contained in saturated bio-char are shown to release far less NOX into the atmosphere and the combination is proving to be a long term soil amendment that reduces the need for fertilizer on croplands.
   As agricultural fertilizers are both a significant source of GHGs and sink for fossil fuel methane a significantly positive resouce shift is possible. The bio-char is essentially carbon that has been secured from the atmosphere and in it's mineral form provides a stable form of sequestered atmospheric carbon. Experiments with fertilization with bio-chars are showing significant advantages in crop yields, water retention and reduced or eliminated fertilizer needs.
   As climate change is proving to be far worse than the current models show it would make sense that we should both reduce our emissions and seek ways to secure atmospheric carbon ASAP. Simple combustion simply dumps the carbon, methanol, oils, nitrates and hydrogen (as H20) back into the atmosphere losing the value of these products as anything but heat.
   We are going to need liquid fuels even if battery operated vehicles dominate and we are certainly going to need cheaper sources of fertilizer as fossil methane becomes too expensive to provide hydrogen for fertilizers. Terra preta methods of carbon sequestration and fetilization offer the potential of a more effective use of available resources. It should also be vigorously explored as an alternative to simple combustion of biomass for power production. We need to get several gigatons of excess carbon back out of the atmosphere as "or else."  
   "OR ELSE" seems to be already beating down our doors.
   
   Put the Carbon Back

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8. 

   Sean Casten Posted 11:22 pm
   24 Jan 2008

   TomYou misunderstand my point about cogen, and I think understate the scale of cellulosic ethanol plants.  The idea that these plants are likely to be small and distributed doesn't make any more sense than the idea that papermills or sugar mills are small and distributed.  All three of those have substantial costs associated with collecting and transporting feedstocks "from the farm", but those costs are greatly swamped by the economies of scale innate to what is, at core, a rather complicated chemical process of pre-treatment, fermentation, and separation.  (Indeed, even in corn dry mills which are comparatively simpler to build, the optimal economic scale is limited by ethanol distribution infrastructure rather than capital: build more infrastructure and those plants grow naturally bigger.)
   This matters because even a "small" ethanol plant (e.g., of the 50 million gallons/year variety) needs on the order of 100,000 lbs/hr of steam to distill the beer.  More is needed for co-product drying (corn mills) or pretreatment (cellulosic plants), but even at this 100,000 lb/hr, you have a huge thermal demand for cogen, vastly in advance of anything that you could cobble together from a few homes (and more consistent, on an annual basis - a key criteria for the capital recovery necessary to justify plant construction.)
   But the stronger argument for plant cogen is the fact that cellulosic materials - unlike corn - come "prepackaged" with comparatively high-BTU fuel that is not fermentable (lignins, oils, etc.)  Corn comes in as essentially a pure carbohydrate, that is almost fully fermented to ethanol in the plant.  (Various processes may extract oils or protein-rich animal feeds from the kernel as well, but on a total volume basis, these are minor relative to the carbohydrate fraction.)  Cellulosic biomass, by contrast - be it wood, switchgrass, or any other reasonably low-cost material - is often 50% or more not-cellulose, by mass (primarily lignin, which is essentially very young coal).  This is the material that forms the "black liquor" in papermills which remains after they covert those (cellulosic) fibers into paper.  And it is really good energy source.  So good, in fact that the energy content is sufficient to produce all of the plants heat and power needs, plus a grid export, without any hassle associated with tying together local thermal loads.  And it's free: it comes in with the purchased feedstock, and has no real product market on the backside.  So a plant can either convert it into energy, or else pay to have it hauled away (and then spend more money to buy gas and electricity to run the plant.)
   As a result, you end up with a fundamentally different energy equation in a cellulosic ethanol plant than in a corn mill.  The latter buys a ton of natural gas and electricity, which is a big part of why people have claimed that the net fossil balance from corn ethanol might be a bit shaky.  But the latter has no such need (and can export power to the grid in the process, displacing more fuel from less efficient, fossil-based central power stations).  This basic economic calculus is identical to that faced by integrated pulp and paper mills, and explains why that industry has played such a big role in the deployment of cogen to date.  
   Note also that there is nothing about CHP that is innately small.  While it is often smaller than central power stations, this is because it is size-limited by the demand for local thermal energy and/or supply of low-cost opportunity fuels.  A cellulosic ethanol plant is a big source of both, and is a great host for a ~50 - 100 MW cogen plant.  (Our company has several such plants in development, and my prior company built a number of cogen plants at traditional corn mills, so I'm pretty confident of these numbers.)
   All that said, I certainly concede that there are some formidable technical challenges to cellulosic   ethanol - but the worthiness of this pursuit ought not be evaluated against a presumption that the plants will be as energetically inefficient as a corn-based dry mill that lacks the inherent advantages of cellulosic feedstocks.

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9. 

   Biodiversivist Posted 6:46 am
   25 Jan 2008

   Sean,These power plants are [would be] pure cogen ...And a cellulosic ethanol plant is [would be] a big thermal energy user ...
   When talking about the potential of cellulosic fuels we should stick to the right tense. Otherwise we can mislead people into thinking that cellulosic ethanol actually exists in a commercially and environmentally viable form when it actually doesn't.
   Taking all the politics out of [corn] ethanol, it is by far the cheapest alternative fuel as far as infrastructure is concerned. Plug in hybrids require less infastructure shift than EVs, but it's still significant.
   We also need to qualify the fuel feedstock in these discussions (corn, cane, cellulose) or readers may be led to think we are referring to corn ethanol when we are actually referring to the hypothetical cellulosic.
   It would be interesting to see some numbers to support the conclusion that "corn" ethanol is the cheapest way to reduce GHG emissions as far as infrastructure is concerned. Ethanol refineries (regardless of feedstock) are not cheap to build. Taxpayers have paid, are paying, and will continue to pay billions for "corn" ethanol. I'm assuming you meant corn ethanol since you used the present tense and the fact that it exists solely thanks to politically motivated subsidies and mandates.
   The Prius not only did not cost the taxpayers, but also required no new infrastructure costs. Plug-ins will create only incremental changes. Some "green" jobs will be created when plug in owners start hiring contractors to run power to the garage, driveway, or curb where their car gets parked. That's good. The latest studies don't show a near term need for more power plants as a result of plug-ins.
   Finally, I think you understate the infrastructure shift required to go to electric vehicles ...
   As with cellulosic, all-electric cars are not viable. We could guess which might become viable first, but I don't want to waste a lot of time on it. Should electric cars become viable, they could slide into place fairly seamlessly because we retool constantly and plug-in cars, entering the fleet in ever-greater numbers as retrofits, may greatly smooth that transition as well. I think you are overstating the shift required.
   Realistically, I find it far more likely that we would see a slow increase in ethanol content in our fuel (cellulosic and otherwise) and a concurrent increase in the deployment of fuel-flexible hybrids and plug in hybrids than that we would go to a 100% PHEV world with biomass cofiring
   Coal is more GHG intensive than oil. Displacing it with biomass would be more efficient than turning it into hypothetical liquid fuels. If you could convert biomass to cellulosic at 45% efficiency (verses 35% at a coal plant), you would still lose another 30% mileage at the engine. You don't need electric cars. But if you did add them into the calculations, you would not need all-electric cars. Plug-ins are also much more efficient than ethanol powered cars.
   Burning it directly at a coal plant would also not require betting the farm that cellulosic will one day become a reality (and even if it does I suspect we will eventually burn much cheaper carbon sink eating cane ethanol from South American instead).
   Unlike corn, cellulosic feedstocks are lignin rich, and therefore supply all the fuel they need to run the plant and even export power to the grid. Thus, where a corn-ethanol plant consumes significant amounts of natural gas and electric power, a cellulosic ethanol plant needs no additional fuel and exports power to the grid. The precise benefit is obviously a function of the specific biomass and technology selection, but is fairly universal. These power plants [would be] are pure cogen, way more efficient than the paltry 33 - 37% efficiency you get from co-firing
   We discussed this briefly when you were defending corn ethanol refineries because they can use cogeneration here and here.
   And as I said there, burning biomass to make electricity for the grid at one of these hypothetical refineries would be exactly the same paltry 33-37% efficiency as burning the biomass at an existing coal power plant. You would only gain efficiency inside that one hypothetical refinery, which because it created a demand for that extra energy that did not exist before, will therefore do nothing to drop CO2 emissions from the electric grid.
   
   In the end, it all comes down to biodiversity. Poison Darts--Protecting the biodiversity of our world

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10. 

    Sean Casten Posted 9:03 am
    25 Jan 2008

    BiodWe've gotten into this before, and lest you think I'm ducking the question, I find the thread frustrating.  Primarily though because at core, it is clear that you and I share the same goals, but come at it from a vastly different set of operating assumptions - and unfortunately, that is a hard circle to square in a stream of blog posts.  It is worth squaring though, because of our shared interests.  (I do not devote any time blogging on the right-wing websites because we don't share the goals.  But I do spend a lot of time blogging on Grist, primarily because I have been party to too many business- and policy-related events where the environmental outcomes were suboptimized by well-intentioned people using flawed assumptions, to all of our mutual detriment.)
    For what it's worth, this isn't meant as any personal attack on you, and I hope you don't take it that way.  Indeed, the assumptions of yours I disagree with (primarily related to corn vs. cellulosic comparisons and more broadly to assumptions about the pros and cons of making disfavored industries cleaner and more competitive) are pretty universal, and to that end, I will (one of these days) put together a more formal blog post to address.  
    So... sorry not to respond in detail here, or in your prior related comment, but one of these days I will.

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11. 

    Nucbuddy Posted 10:37 am
    25 Jan 2008

    Slavery = wealth. Are you sure?Biodiversivist wrote: Some "green" jobs will be created when plug in owners start hiring contractors to run power to the garage, driveway, or curb where their car gets parked. That's good.
    How do you figure it is good to create jobs?
    Saving labor, producing more goods with fewer man-hours, is widely perceived not as progress but as a danger. I call this the make-work bias, a tendency to underestimate the economic benefits of conserving labor. Where noneconomists see the destruction of jobs, economists see the essence of economic growth: the production of more with less.

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12. 

    Tom Konrad Posted 3:41 pm
    25 Jan 2008

    SeanI agree with all your points about how cellulosic ethanol with cogen would be far better than corn ethanol.  
    However, in the comparison between biomass cofiring and biomass/cellulosic cogen, I think we're both suffering from a paucity of numbers... the question we have to ask is how far we could drive in a PHEV powered by your cellulosic ethanol+electricity vs. how far you could get in an EV powered by electricty from cofiring.
    There's probably more energy in the cellulosic ethanol+electricity scenario, but would the lower efficiency of an ICE lead to lower miles?
    I don't know the answer to this... there are probably too many variables to pin down.
    On the subject of large CHP, I once had a tour of the Coors coal fired power plant in Golden... it provides all the electricity and process heat for the brewery, as well as providing some space heating to the School of Mines 1/2 mile away.

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13. 

    MissCanthus Posted 4:30 pm
    25 Jan 2008

    Cofiring biomass with coalHere in the UK, we are progressing well with developing systems with leading power companies for cofiring energy crops like Miscanthus with coal. I therefore agree with much of the comment in this article. Direct production of electricity with biomass could be an attractive and economic 'biofuel' for future transport.
    
    In the EU auctioning carbon from 2013 will provide a further economic driver OR accelerate closure of coal fired power stations.
    
    We have never seen Miscanthus and biomass as anything other than a useful contributor rather than a dominant one.
    
    But for generating small scale LOCAL heat and electricity through distributed generation, Miscanthus biomass definitely has a great future.
    
    Bical Miscanthus

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14. 

    amazingdrx Posted 4:42 pm
    25 Jan 2008

    Dumb and dumberCellulosic ethanol dumb.  Burning cellulose to generate power for the grid, even dumber.
    Biogas from waste, manure and biomass, with most of the biomass returned as a soil amendment/fertilizer, thus building the carbon sink ability of soil and providing clean kwh to backup the renewable smart grid.  Used in solid oxide fuel cell/turbines with triple the efficiency of combustion.
    With Vinod and his critics providing lame alternatives, where is the leadership for this energy revolution coming from?  Bloggers?  Amazing.
    
    http://amazngdrx.blogharbor.com/blog

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