Insects add 4th generation to biofuels debate

Good news from Norway. Sustainable biofuel production is perhaps another tiny step closer. Soon we may be able to start burning bugs.

Biofuels received a lot of bad press over the last three or four years. That is because it seemed to be the plan we would be driving our cars at the direct cost of food (US corn bioethanol) or rainforest (Brazilian sugarcane bioethanol) – or both actually, for global agricultural land demand is on the increase anyway, and as always at the expense of forests. More farmland anywhere, means less forest elsewhere, is the rule of thumb.

With rising food prices and a speedy decline in biodiversity that may seem bad enough, but the matter reached irony when calculations started to show these classic biofuels actually came at a bigger (US corn) or more or less equally high as Saudi oil (Brazilian sugarcane) net CO2 emission per gallon or per mile.

The total amount of carbon locked in the actual biofuel molecules is not the problem here. That carbon sort of belongs in the atmosphere anyway, as part of the fast, natural carbon cycle – supposedly in balance. You have to remember it was sequestered by the actual crop you’re burning just the year before. The inefficiency of the production process is the problem. That is the sum of the energy use and the GHG emissions of the agricultural machinery, the large transport lines, soil oxidation, the fertilizer production and use – and not to forget about the increased deforestation, still responsible for some 15 to 20 percent of global anthropogenic CO2 emissions. To go short: upscaling agriculture proved not to be the right answer to combat the side effects of modernity.

As criticism on biofuels grew, so did the hopes for electrification of road transport. So, have biofuels become redundant even before we ever managed to mass-produce them? Well, you can’t make an intercontinental flight on a battery. You can fly a 747 on biokerosine. Biofuels may still have their role to play.

Fortunately alternative biofuels are being developed at present – the ‘second generation’. These are harder to produce, but come at a much smaller carbon footprint, making use of biowaste, crop residue mostly. You don’t need extra acres for that. Once you manage the chemistry and are able to turn the straws, the chaff and the wood chips into sugars – with help of microorganisms – you’re just a last easy step away from having ethanol.

Biofuels from algae are perhaps even more promising, as the production of biomass can be fast – and the transition from algae biomass to actual fuels is relatively easy. As algae don’t necessarily require any (agricultural) land space, the algae biofuels are sometimes dubbed the third generation – equally CO2 extensive as the second generation.

Now on Thursday a group of scientists from the Norwegian University of Life Sciences added another cheerful bit of science news to fuel the debate. Helped by a special enzyme they managed to break down nature’s second most prevalent polymer, chitin (the first is cellulose, building block of all things wooden – the big challenge for the second generation biofuels) into a sugary substance – within two hours, according to lead author (they published in Science) Gustav Vaaje-Kolstad.

Chitin you should know is that hard substance insects use to shield themselves. And also the remains of lobsters, crabs and shrimp can now be thrown on the big biomass pile.

It should be said chitin and cellulose are not that different. The Norwegian research does not focus on insects – it focuses on creating carbon extensive biofuels from biomass in general. But then again, one day, every gram will count. Biomass is money.

(c) Rolf Schuttenhelm | www.bitsofscience.org

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