Burning biofuels instead of fossil fuels reduces the amount of carbon dioxide we pump into the atmosphere.
But there’s a downside. Growing biofuels uses land that could be used for growing food, and there’s already barely enough land for growing all the food the Earth’s human population needs, and what about some habitat for the world’s beleaguered wildlife?
Those are basically the cases for and against biofuels, but neither of them is really the whole truth. As so often, it’s not as simple as that.
The big error in the first statement is that it’s only true if the biofuel is being replenished by new growth as fast as it’s being burnt. (Some folks will try to tell you that as much fossil fuel is used to produce the biofuel as the amount of biofuel that’s produced, but that would only be true if the farming and processing were spectacularly inefficient.)
But if you’ve cleared an area of rainforest to make space for an oil palm plantation, for example, it’ll take many decades for the CO2 saving from using palm oil instead of mineral oil to outweigh the CO2 produced in clearing the rainforest. And that’s not considering the other objections to clearing rainforest – particularly loss of biodiversity.
The big error in the second statement is that it simply isn’t true. There’s plenty of land to grow all the food the Earth’s human population needs. The key word there is needs – as Gandhi famously said, “Earth provides enough to satisfy every man’s need, but not every man’s greed”. Actual consumption of food – and everything else – expands greedily to consume all that is available, however much that is. People on Earth are starving not because there isn’t enough land to grow what they need, but because someone else is eating it, or wasting it.
Meat consumption is the most glaring example. In some (rich) parts of the world, people eat far, far more meat than they need – in fact, so much that it’s seriously damaging their health. Yet meat production is grossly wasteful, and accounts for the bulk of the world’s primary agricultural produce, despite producing only a small proportion of the food eventually consumed by humans.
The world most certainly could not feed its human population an American diet, but it could feed several times its present population a good, healthy diet. No, I’m not suggesting a starvation diet of the kind some poor people have to subsist on today – a healthy diet, with some meat for those who want it.
And therein lies the key. The world could provide that healthy diet for the current global population, and have substantial spare capacity left over to grow biofuels.
The priority is clearly that healthy diet for everybody. We currently don’t even meet that priority. After that, we can choose what to do with the “surplus” land: do we want to eat a little more (particularly meat), use some biofuel, or have more wildlife habitat? Those are the real choices. It’s a political question. We could perfectly well choose to grow a biofuel crop instead of some of the grain we grow to feed to animals – but we shouldn’t clear rainforest to grow biofuels, or for animal feed. To be responsible, we should cut down our meat consumption correspondingly instead.
The real situation at present is that poor people are being driven from their land (in India) and rainforest is being destroyed (in Malaysia and Indonesia) to plant biofuel crops. Just as poor people have in the past been driven from their land to provide sheep farms, cattle ranches, sugar plantations, rubber plantations, peanut farms or shrimp farms for the benefit of the rich. “Driven from their land” is often actually literally murderous.
People say that international trade is good for poor countries. Well, it’s generally good for the rich in poor countries, but it’s often a total disaster for the poor in poor countries. Trickle down? You don’t want that kind of trickle.
As an energy source, biofuel is pretty good. There are liquid biofuels (biodiesel, ethanol and methanol) that can be used for transport. When biodiesel is produced, there’s a substantial by-product of solid biomass that can be burnt in an electricity generating station. The value of this solid residue is often ignored by biofuel’s detractors. Simple methods of producing ethanol also leave solid biomass that can be used in this way. Alternatively, in either case, there are more advanced methods by which the solid residues can be used to produce either ethanol, or methanol, fuel gases, and a smaller burnable solid residue.
For electricity generation, biomass (whether as a byproduct of liquid biofuel, a byproduct of food production, or as the primary product) is less efficient in terms of megawatts per hectare than solar panels or solar thermal electricity. However, its capital costs are much lower and its energy can be easily stored, so it’s a good complement to intermittent sources of power like wind and solar.
Biofuel is carbon neutral – that is, as much carbon dioxide is absorbed by the growing plants as is produced when they’re used as fuel. This is only true if you don’t use fossil fuels to run your tractors or in fertilizer manufacture, but it uses much less fossil fuel than the amount of biofuel produced, unless you’re incredibly wasteful. You can manage with a small percentage of your biofuel product to run your tractors, and use no fossil fuel whatsoever for them. You can manage without any artificial fertilizer at all, either accepting a somewhat lower yield of biofuel per hectare per year, or using manure and sewage as fertilizer.
One thing this essay has not touched on is growing algae in tanks. That’s a whole different game, and may well have some promise – particularly if it can use salt or brackish water, and especially if it can be done in places where nothing else would grow. I’ve not researched this – but I know a man who has, and might get him to contribute a piece...