Monday, 2 June 2008

If biofuels are the answer, what is the question?

One of the biggest problems with both climate change and the growing threat of peak oil is that it's all too easy to fall into the trap of subsidizing special interests, rather than actually tackling the real issues.

Either we accept that these problems are real (singly or collectively) and we focus on solutions, or we don't. In either case spending good money on non-solutions is idiotic. If there is a real problem, we need to solve it. If there isn't, why are we wasting valuable resources on unnecessary research, industries that don't stand up to competition and that, in any case, wouldn't solve the problem if it were real?

My own position is that there is far too little cause for doubt on climate change to mess around: we should stop navel contemplation and get on with solving the problem.

I am a little less certain on peak oil. Hubbert's original theory worked well for a single market, the US (he accurately predicted the US peak as 1970-5975). When US oil discovery peaked, it made sense for oil companies to switch their focus to other parts of the world, rather than pursue diminishing returns (oil that was harder to find, harder to extract, or both). The same equation does not apply worldwide: oil companies can't start exploring another planet for oil. So more expensive exploration and extraction in combination are very likely to push the peak well out beyond Hubbert's calculation.

However: the key issue is that we are starting to deplete the cheaper resources, coincidentally with massive growth in new economies (especially China but also India), so prices have only one way to go, and that is up. Add that to climate change, and there is a powerful argument to look for alternatives to fossil fuels.

Biofuels are at best a small part of the solution because there isn't unlimited agricultural land available to turn over to fuel production. At worst, they exacerbate the problem, as in countries like Malaysia and Indonesia where massive amounts of greenhouse gases are emitted through deforestation for oil palm plantations.

Wikipedia has an informative article on the world leader in ethanol, Brazil.

To put matters into perspective, world ethanol production in 2004 was 10,770-million gallons. In the same year, the US alone consumed nearly 14 times that amount of petrol (gasoline for American readers: over 3 billion barrels, about 140-billion US gallons).

Brazil is in a favourable position for growing a lot of sugarcane for fuel; it is unlikely that their production could be scaled up through enough other countries to make a meaningful dent in the problem, even if so doing would not displace food crops, or result in other environmental disasters.

The US could significantly increase available agricultural area for biofuel crops with a total cessation of feeding food, grown on land that could produce human food or energy crops, to farm animals. Not only would this be a more efficient form production, but the cows would have less fat, reducing the human obesity problem. However, it is only in comparatively wealthy countries that this kind of land exists for conversion. In poorer countries, cows eat grass. And not many countries are in the position of Brazil, with a significant fraction of farmland available for sugar cane.

In any case, oil, coal and biofuels are an incredibly inefficient way of storing solar energy. A plant stores between 3 and 6% of the incident solar energy, compared with solar cells, which are supposedly inefficient because they 'only' covert 15-20% to electricity (do a search on "solar cell efficiency": there are some far better efficiencies in research labs). Add in all the other losses from converting plants to a usable form of fuel and the losses from burning them to create the form of energy we actually want (motion, electricity, etc.) and they turn out to be incredibly inefficient. In the case of fossil fuels, the stupendous inefficiency of their production is masked by the fact that we waited hundreds of millions of years before bothering to use them.

If we can find an efficient way of storing electricity, we will solve the entire energy problem with the exception of the real hard case, air travel.

The long-term solution is energy sources that do not require burning carbon or hydrocarbons. If we are serious about dealing with climate change and the threat of peak oil, we should be putting massive resources into solving this problem. In any case, it's stupid to put waste big money on non-solutions.

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