Can’t see the Future for the Trees
I think both contribute to the very problems they seek to address.
As the world heads towards the peak in global oil production, we find ourselves desperate for replacement liquid fuels. Environmentalists want a closed-cycle carbon-neutral energy source, farmers want a fair price for their produce, while car companies and mainstream politicians are looking for a way to promote a greener vision of unabated consumerism.
However, despite all the hype, we must stop and consider carefully before rushing headlong into what might prove a tragic irony of the most devastating proportions. In pursuing an apparently ‘green’ fuel we may inflict more damage than we circumvent.
According to Earth Policy Institute President Lester Brown’s calculations, the amount of grain needed to fill a single 4WD 100-litre petrol tank with biofuel could feed a person for an entire year. As new ethanol refinement plants have come online in recent years, food production has not risen to meet the added demand. Biofuel demand is already creating a global grain prices ‘chain reaction’.
Mainstream biofuels advocates, many with the best intentions, are therefore essentially promoting the radical expansion of industrial agriculture, which, as I argued last week, is the most destructive practice humans have so far inflicted on the biosphere.
On top of this, our food system has long been a voracious consumer of fossil fuels. Fossil fuel energy is used to produce pesticides and herbicides, in machinery fuel and production, in electricity for cooking, processing and packaging, and in transportation and irrigation. In the US, it takes around 10 calories of fossil fuel energy to deliver every calorie of food to the consumer. Around one third of the proteins in our bodies are the indirect product of the nitrogen fertiliser industry, which uses natural gas as its feedstock.
If these unseen fossil fuels are embodied in our food, two obvious questions present themselves. Do industrially produced biofuels actually deliver more energy than it takes to produce them? And, how are we going to even feed ourselves in an energy-scarce world, let alone produce biofuels?
The first question is a point of some contention.
Professors Tad Patzek from the University of California, Berkeley and David Pimentel of Cornell University say no; in everything from switchgrass to corn ethanol, more energy is used than is produced. They are harsh critics of an industry Patzek refers to as ‘laundering fossil fuels’. It’s a position supported by the fact that in 2005 the US National Corn Growers Association called on the US Government to increase natural gas drilling to support ethanol producers.
If Pimentel and Patzek are correct, then these so-called green fuels are worse than their fossil fuel equivalents. But their findings are not without controversy.
Biofuel advocates claim that ethanol and biodiesel produced from corn and soybeans offer energy returns in the realms of 30 to 70 per cent more energy than is invested. This concept of Energy Returned on Energy Invested is crucial. Historically, oil has offered returns of up to 100 to one. That is, for every barrel of oil used in exploration and production, 100 barrels were brought to market (although that figure is probably below 10 to one now).
A society based on a resource that offers returns as low as 1.7 to one — one of the more optimistic levels claimed by ethanol promoters — would look profoundly different to anything we know today. In such a society, the biofuels industry and the essential services which support it would use 10 units of energy for every seven units available to the rest of society. So, even if we take the optimistic figures, we are still faced with a serious problem.
On the other hand, some of what we might traditionally consider to be unenvironmentally friendly practices may turn out to be our best options.
Thanks to Fiona Katauskas.
Former forest protestor and a natural resource manager, Mark Feltrin, promotes gasifying wood (where wood is heated without the presence of oxygen, releasing flammable gases) for heat and electricity production.
In the same breath, Feltrin talks about the importance of integrating ourselves into the Australian ecology. The juxtaposition might sound unfathomable, yet similar perspectives have been put forward by other serious environmentalists, from permaculture co-originator David Holmgren, and former Australian Commonwealth Scientific and Research Organization (CSIRO) scientist, biofuels expert and co-founder of the Victorian Greens, Chris Mardon.
As a nation, it’s difficult for us to imagine sustainable forestry. ‘Currently we deal with forestry in the same way we deal with mining for coal’, says Feltrin. Yet in Europe and other parts of the world there are long established cultures of sustainable harvests and caring for forests for future generations.
David Holmgren says that carefully managed forestry is the most viable source of biofuels. ‘Cellulose from existing and regenerated forests, managed on long rotations for multiple values, represents the most sustainable biofuel option — and also the best net energy return on energy invested, mainly because no fertilisers are needed to grow forest trees,’ he says.
Chris Mardon’s paper ‘The feasibility of producing alcohol fuels from biomass in Australia’, will soon be published in the International Journal of Global Energy Issues. He notes that ‘the potential for planting trees to control salinity is huge, and just the thinnings from those areas would support a substantial methanol industry.’
Mardon believes that truly sustainably produced biofuels could be a significant contributor to the Australian liquid fuel mix. ‘Producing ethanol from crops is not a sustainable way of producing renewable fuels for use as urban transport fuel. However, the production of methanol from wood or cellulosic crop wastes could produce very substantial quantities, albeit at a higher cost than petrol is now.’
These efforts would require decades of reafforestation and investment, and while they may soften our fall at the end of the age of cheap oil, they cannot support the continuation of a full-blown consumer society.
‘The production of biofuels on farms to ensure farmers can plough, sow and harvest food for Australians and our customer abroad is a prudent and wise move in an energy scarce world,’ says Holmgren. ‘However, the idea that we should plough more land or reduce food production so Australians can continue to go shopping for food they could more efficiently produce at home, is just one of the many mad ideas that has currency as we contemplate the peak and decline of global energy supply.’
Very short rotation (less than 15 yrs) monocultures of soil depleting trees such as pines or eucalypts could be more damaging than pastoral farming on the same land. Very large scale clearfelling and total biomass harvesting of native forests with large machinery would be a stupid mistake but no worse than plowing all our pasture land to grow fuel crops. But the technical difficulties in sustainable forestry are simple compared with the very serious problems of how we make agriculture sustainable. Despite the poor track record and reputation of forestry in this country, it is easier to practice sustainable forestry than it is to make agriculture sustainable. If we don't develop the small scale examples of sustainable forestry now that can be replicated to sustain relocalised economies, then our descendents will curse us for burning all of oil and gas as they clearfell the national parks and reserves we created in our affluent naivety.David suggested a way of tackling both forestry sustainability and future reduced availability of nitrogen fertilisers:
If reafforestation includes a predominance of fast growing nitrogen fixing trees palatable to livestock (mostly legumes) this will help alleviate the future shortfall of nitrogen fertilizers by creating agroforestry systems that use animals to cycle some of that nitrogen in foliage back to cropping land. The farm forestry and permaculture networks in Australia have pioneered small scale examples of such multipurpose reafforestation.Mark Feltrin went deeper into the tensions between human energy wants and intrinsic environmental values:
I've had to grapple with the emotive side of it, but also intellectual side of forestry. The emotive side of it in one respect is loss, loss of beautiful things. The intellectual side is understanding that these beautiful things also have intrinsic human value, not just environment ones. I've tried to, I've got myself a forest property. It's manifested in me trying to find the middle way – where the human can actually be incorporated into a natural environment. Almost like a modern version of what indigenous might be. How can modern humans live for 50,000 years, particularly within this environment? I guess what we're trying to do in Gasification Australia, is promote a philosophy in which the human being fits into the environment, in an ecological and societal sense.He also thinks that the discussion on sustainable biofuels is more complicated than making an agriculture bad / forestry good divide:
We don't necessarily favour wood over agriculture. We favour natural systems, polycultures over monocultures. In a grassland it might be preferable to utilise biomass via grasslands, if you're living on the coast... I know somewhere in Asia they're using mangroves. In the Australian context we're quite keen on utilising forest types along the divide, because it's marginalised land, we we see a benefit there.I should also have mentioned Chris Mardon co-wrote "Beyond 2025: Transitions to a Biomass-Alcohol Economy using ethanol and methanol" with Barney Foran of CSIRO. The report can be downloaded from: http://www.cse.csiro.au/publications/1999/biomasseconomy-99-07.pdf
I am forced to point out that David Pimentel, whose research contends that corn ethanol is a net energy loser, doesn't think wood ethanol is any better, mostly because of steam costs in the conversion to ethanol process. I discussed this with Chris and I also contacted Pimentel about it. Pimentel said while he still thinks ethanol is not an energy winner for wood, he has seen promising research regarding methanol, while wood fuel for electricity production offers even higher returns. So I'm still a bit concerned about that. However, trees, and perennial polycultures, are going to be inherently better at capturing sunlight and soil resources than industrial monocultures, while requiring radically less maintenance (and energy inputs) to grow. At point of harvest the ER/EI is massively higher for forestry than industrial agriculture. It is in the processing to liquid fuels that the ER/EI potentially goes down a lot, but there is a lot more scope for improvement and other creative uses than there is for agricultural products. Chris believes the methods he has studied also favour methanol, "and that would cost about 90 c/L ... for a plant producing 100,000 tpa." Considering that, and David Pimentel's response, I felt satisfied enough to make the case promoting sustainable forestry in this way. -AF
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