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Biofuels can help solve climate change, especially with a carbon tax

Posted on 14 March 2018 by John Abraham

Facing the reality of human-caused warming, we now look for ways to reduce the problem so that future generations will not inherit a disaster. So, what can we do now to help the future?

The easiest answer is to use energy more wisely and quit wasting our precious resources. Second, we can increase our use of clean energy, particularly wind and solar power. These are great starts but we will still need some liquid fuels and for those, we can make decisions about the best fuels for the environment. There has been extensive conversation recently about biofuels and how they may help solve the climate problem.

The term “biofuels” has many meanings, but basically they are grown fuels (like corn ethanol) that we can use instead of fossil fuels (like petroleum). While biofuels can be any fuel produced from plant material, historically they have been produced from food crops such as corn and soy. But, new technologies are enabling biofuel production from non-edible gases, wood, and other plant waste material.

The beauty of biofuels is that they suck carbon dioxide out of the air as they grow. When we burn them in our automobiles, we release carbon dioxide, but it is the same carbon that the plants absorbed while growing. Just on that basis, biofuels appear to be zero net emitters.

But this view is too simplistic. It takes energy to grow biofuels; it takes fertilizer, tractors, transportation, and energy to convert the plants to liquid fuels. Planting and growing these crops can also change how much carbon is stored in the soil. And using existing food crops or arable land for biofuel production might lead to deforestation if farms are expanded elsewhere to make up for lost food production.

So, if you want to accurately assess the impact of biofuels, you need to look at what’s called a “life cycle analysis,” which basically means the effort it takes to grow the crops, harvest them, convert them to fuel, transport them to distribution sites, and combust them. 

I have done some research in this area. Back in 2009, I did a study with my former student Fushcia-Ann Hoover, and we compared different feedstocks for ethanol. You can have corn, soybeans, sugarcane, switchgrass, poplar trees, and others. What is the best crop? Which is easiest to grow? Which is best for the environment?

What we found, way back in 2009, is that if non-commercial crops were grown, you could actually end up with fuel that was significantly cleaner than petroleum. The trick was finding clean crops that don’t need a lot of fertilizer, water, and other inputs. Corn ethanol for instance is not the best choice. You need so much water, fertilizer, and other costs, that it almost doesn’t make it worthwhile. But other crops such as switchgrass, grown on marginal lands, have real a potential. Marginal lands are farmlands that are not optimal for growing crops.

Our conclusion in 2009 was straightforward. Don’t use good cropland for biofuels. Rather, use marginal croplands, with minimal water and fertilizer, to create plants that can be converted to biofuels. 

But our conclusion wasn’t the end of the story. There are other details that researchers should consider. For instance, how far from the croplands to the refinery? How much energy is needed to transport the fuels? All these issues matter and they were the focus of a recent research paper just published in Nature Energy. This study used an actual biofuel refinery located in Kansas for the basis of the study. And the authors counted all the emissions that occur during the lifecycle analysis of these biofuels. They realized that marginal croplands give lower yields, so there are competing issues of productivity and greenhouse gas reduction.

Then there’s the complicating factor of economics. The price of biofuels and the price of greenhouse gases matter. If society is willing to pay a small pollution charge like a carbon tax, it supports the producers of clean energy. But if society doesn’t put a premium on clean energy, it’s harder for clean industry companies to thrive.

In the new study, the authors discovered something fascinating. The found that the choices a farmer may make regarding what land to use for biofuels and how much fertilizer to use depend strongly on the price of clean fuels and the cost of greenhouse gases. Simply put, it we put a reasonable price on carbon pollution, farmers will be able to grow switchgrass, poplars, and other species, reduce greenhouse gases, and make money.

But, if there is no cost to carbon pollution, farmers will be motivated to spend more money on fertilizer and that, in the end, will lead to more emissions. While all the scenarios resulted in large emissions reductions compared to gasoline, the reductions were especially large for the scenarios that included a carbon price.

So, there is a delicate balance. The balance is made more clear when we realize that farming location matters. If biofuels are grown close to refineries, less pollution is created in transporting the fuels to the refinery. However, this limits cropland choices to those nearer to refineries. 

With this balance of competing factors, the authors find room for improvement; currently we are not optimizing the performance in terms of both economic and environmental factors. In order to do this right, we have to balance all these mentioned issues. We can’t just focus on transportation costs, fertilizer costs, and land quality costs; we have to consider these costs all together as a system.

I spoke to the lead author of the paper, Dr. John Field, from Colorado State University and asked him about the significance of this work.

Click here to read the rest

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Comments 1 to 6:

  1. This article makes a very good case in all respects,  however using biofuels in blended fuels for cars is senseless to me.  I suggest limit use of biofuels to air travel and shipping which are hard to electrify, to minimise intrusion on forestry and agricultural land. 

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  2. I agree with nigelj but would add out-of-the-box developments such as letting long distance transportation take longer along with reducing the enegry needed to accomplish the transport.

    That would mean considering ideas like sails to assist ocean transport (already being developed) and using derigible-plane hybrids to allow natural winds to assist the transport when possible (also already being developed).

    The key is to be willing to have things happen Slower when Slower is understood to be Better for the Environment and Resource Management.

    However, the correction of the incorrectly over-developed unsustainable and harmful aspects of the existing economy should not be 'Slower to avoid penalizing people who do/did not care about the impacts of their chosen way of obtaining Personal Benefits', people who ignored warnings that what they enjoyed benefiting from was unsustainable and harmful, warnings that were undeniable 30 years ago and have continued to become less deniable with each new year of increased awareness and understanding.

    A significant carbon tax would be the motivation for very creative development of alternatives, more than biofuels. For creativity to produce wonderful results, it has to be motivated to be prioritized over 'creative attempts to delay the development of awareness and understanding in the general population of the need to correct many existing developed popular ways of enjoying life and profiting'.

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  3. Biofuels take a lot of energy to produce and with the best will in the world, tend to use resources that could better be put into producing food.  Let's cut the gorgon knot and just go straight for batteries.  In a car, for instance, it is far more energy efficient to simply charge a battery than to produce biofuel and transport it to the petrol station.  The network already exists.  Hydrogen, of course, as Elon points out (admirably keeping his cool) is simply a not starter for transportation use.  Electrolize, liquidify or compress, transport and then get a product that doesn't have the energy density of liquid fuel.  No way.  As for a carbon tax, great if you use the tax and dividend formula.  Carbon trading simply leads to corruption.  A carbon tax at the point of exit from the ground or entry across your boarder is clean, easy to administer and unavoidable.  While we are at it, let's stop subsidizing fossil fuel.  What a joke.  So I've had a cathartic blowing off of steam but none of what is needed will come to pass.   There is one solution and only one solution to all our problems.

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  4. This is an endorsement of William's "one and only solution", which I would prefer to describe as a "pre-requisite to many solutions" in an even more foundational way than carbon fee and dividend (CF&D); in fact, it's probably a pre-requisite to getting CF&D passed; end private payments to legislators, i.e. give them modest amounts to conduct election campaigns funded by tax-payers.  Our return on investment would be huge in terms of getting policy passed that actually benefitted us 99% rather than Big Coal or Big OIl.  I hope you don't delete this as a political comment, even though it is a bit, because surely you realize that solutions to climate change are inevitably political, e.g. we need legislation to enact CF&D.  When we've got CF&D, the best solutions will arise and it don't matter whether they involve sustainable biofuels, batteries or sheep dung (which, I don't know but, may be a contender in New Zealand where William appears to reside).  Early on in the last US election there was a contender for President who espoused that platform but he didn't get very far, probably for lack of campaign funds.  But might this be done with crowd-funding through the internet?  Personally, I'm not at all wealthy but just on principle I'd send something to such a candidate even though I'm not even American.  If a good portion of 7 billion people did the same, maybe he or she could succeed next time.  I'm too old, but this is a call to arms, a great opportunity, for all you young aspiring politicians, full of piss and vinegar, who understand climate change to get on with this.

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  5. Carbon fee and dividend is revenue neutral, flexible, and treats people fairly. We wont find a better form of tax mitigation strategy in environmental, economic and social terms. Theres no magic bullet.

    Money in politics is a huge problem. It only takes one large wealthy lobby like the fossil fuels lobby to distort things enough to have a disproportionate influence. Environmental and citizens groups can't compete with this form of corporate funding.

    We really do need to get money out of politics, or even just have some form of limit. I'm fairly sure Norway has publicly finded election campaigns, and Britain has some sort of limit on campaign spending. New Zealand has upper limits on campaign spending. 

    However things are unlikely to change in America, and attempts to put caps on spending have been struck down by the courts as unconstitutional. Hopefully more environmentally conscious millionaires contribute to election campaigns in America, to dilute the effect of people like the Koch Brothers.

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  6. Regarding the troublesome child of biofuels.

    While the article makes a good case for biofuels and a carbon tax makes sense, I have always been a little bit sceptical of biofuels. For example, to scale biofuels up to fuel significant parts of the entire transportation sector is going to undeniably intrude massively on forestry and agricultural land, because scrub lands are limited in area ( I vaguely recall about 10% of land and much of this wont be in suitable growing climates).

    Using established forests for biofuel crops simply doesn't make sense given forests are good carbon sinks, provide timber and biodiversity. Do we really want to replace the Amazon Rainforest with fast growing grasses and small trees? 

    Using crop land for biofuel planting is senseless,  given a population heading towards 10 billion by 2100 is going to require more food.

    The more likely and preferred path for biofuels is grazing land will be used for biofuel planting. This is plentiful land, and cattle are not the most efficient form of provision of food energy, so some could be replaced with biofuel crops and also food crops.

    However grassland soils are already very effective carbon sinks with potential to be even more effective if managed well. In some parts of the world carbon rich grassland soils are ten metres deep. So someone better be analysing whether biofuels are a better strategy than this already established soil potential to sequester carbon.  

    At the very least we need to be considering how much grassland is viable to be used for biofuel crops. I would suggest a limited ammount is feasible.

    Therefore I think we have to make basic choices about how much land is viable for biofuels and what parts of the transport sector would benefit most form their use.   Someone need to develop a global plan or strategy for biofuels and use of land in general for negative emissions schemes.

    In this respect, using biofuels as blended fuels for cars is senseless, given the speed electric cars are developing. You don't need modelling to show the obvious.

    Yes I realise biofuels are about the only way of improving the carbon emissions of older cars, but if you were to look at the advantages of something like a 20% blend and all the other issues involved biofuels are probably achieving almost nothing. The whole petrol fleet of cars could be replaced in decades by electic cars if we wanted.

    Instead apply biofuels to those things where alternative approaches are limited, like air travel and perhaps sea travel which are hard to electrify. Even there, we do have an alternative approach of simply using fossil fuels, and offsetting this with conventional forestry planting or garicultural soil sinks. Has anyone modelled using biofuels as against using fossil fuels with forestry carbon sink offsets or soil cabon offsets?

    And hopefully OPOF is right and alternative ways are found for powering ships that don't require biofuels or reduce thier use.

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