Friday, November 03, 2006

Curbing Car and Plane Use.

There seems to be a full-on conflict between the insistence for cuts in CO2 emissions and securing fuel supplies on the one side, but pitted against inexorable growth on the other. In the lead article of the Independent yesterday "Plane Crazy" (2 November) the intention is cited to treble the number of air flights by 2030. The U.K. uses 12.3 million tonnes of oil annually to supply its current demand for aviation, from a total of 57 million tonnes used for transportation altogether. Hence, quenching this rising thirst for plane travel would require an extra 24.6 million tonnes, or an increase of 43% in our overall consumption of imported oil. How does this square either with breaking our dependency on imported fuel in the U.K. or meeting the government's CO2 emissions targets (since this "oil" will of course be burnt and end up as CO2)? In today's Independent (3 November) I read that fish stocks will have disappeared by 2048, but that presupposes there will continue to be enough oil-fuel to run the fishing fleet to catch them. We are now close to the peak in world oil production, beyond which supply will actually fall, hence projecting continued growth in aviation or fishing ignores the matter that all such activities are underpinned by a declining energy source. It makes no sense.

The following letter and reply was published in this month's Chemistry World. The text in the [brackets] was edited out, but is of course the crux of the matter.

From Chris Rhodes.

The RSC Policy Bulletin article entitled Growing energy (Issue 4, autumn 2006, p5) notes the commitment to biofuels by the US and UK.

To replace even 5 per cent of the fuel consumed annually in the UK with bioethanol would require turning over around 6300 square kilometres of arable land for the purpose, or 10 per cent of the total arable area of the UK, which would conflict with food production.

The article talks about converting waste products from existing agriculture to ethanol, for example wheat straw. This sounds like a perfect solution. In fact, it would at best provide the equivalent of just 6.5 per cent of the total fuel currently used. At first sight, the figure seems rather feeble, and so it is. There is no way we can produce enough ethanol to match our current level of fuel use, either using biomass waste or without compromising food production. On the other hand, if we move to systems of energy efficiency: living in localised communities, which would cut fuel demand by 90 per cent, then 6.5 per cent of that remaining 10 per cent begins to look significant.

[Otherwise we can neither break our dependency on imported fuels nor meet the government's targets to reduce CO2 emissions].

I am reassured that survival is possible for the UK in terms of intrinsic fuel supplies, but only given a paradigm shift in the way we live our lives.

Details of calculations on energy provision can be found on the Energy Balance website.

C Rhodes CChem FRSC
Reading, UK

Jeff Hardy, Environment, energy & sustainability forum, RSC, replies:

The RSC agrees that energy efficiency is critical in enabling the UK to meet carbon emission reduction targets and to cut fuel demand. This was one of several key messages in the RSC response to the DTI energy review.

However, if the UK is to meet the imminent targets of the renewable transport fuel obligation (5.75 per cent by 2010 and perhaps 10 per cent by 2015) without significant imports of biofuels and with minimum competition for arable land then biofuels must be produced from agricultural and forestry waste. Significant research challenges remain before biofuels from this route are economically competitive.

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