BBC - The Broadcasting Bollocks Corporation
07 Aug 2007 - Bruno Prior
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Home Planet today, Dr Lynn Dicks, pronouncing on the relative merits of recycling and landfilling, in terms of energy-consumption and carbon-footprint, said:
"Various people have looked at this from the point of view of greenhouse gas emissions, and again there are various different estimates from different people, but one particularly academic piece of research that I found was a full Lifecycle Assessment of the greenhouse gas or the CO2 emission from waste - either disposal of paper, including manufacturing of new paper and disposal to landfill, or recycling paper [Presenter interjects: And the lorry-loads that would be involved in that because that's something that Phil mentioned] and including taking the waste to the recycling facilities, disposing the residual waste after recycling... This was done by a consortium of people at UEA (University of East Anglia) and University College, London in 1995. It was all based on Milton Keynes, and what they found was that... oh well, I'll give you the figures - recycling paper produced about 50 kg of CO2 per tonne; if you disposed of it in landfill and made new paper, 550 kg of CO2 per tonne. So, it's much better to recycle."
1995! Our information and waste disposal techniques haven't improved since 1995? Oh well, if this is what the recycle-nuts want to hang their hats on, let's have a look at it. You can download it from here.
Take this, from p.11:
A second problem that occurs at the manufacturing stage is the scarcity of data, particularly with regards to the manufacture of products using secondary plastic materials. Whilst information concerning energy use is sometimes available, data for the remaining environmental inputs and outputs is either commercially sensitive or simply unreported. In this exercise, the process data (emissions arising directly from the process) has been taken as being identical for both primary and secondary plastics, but an energy saving (and thus the associated emissions of generation) of 77% is obtained by using secondary materials, as suggested by White, Franke and Hindle (1995).
Or to put it more succinctly, "we don't know how much energy is used in production of items from recycled feedstock, so we're going to assume it's 77% less than in the same processes using raw materials." That's how to get the "right" result. Use assumptions that make sure you get the desired outcome.
Even more questionably, from p. 13:
For each average tonne of waste which is disposed of to landfill in the UK, 81% by volume of the gaseous emissions are released to the atmosphere, 13% are flared, and 6% are used in landfill gas generating schemes (Williams, 1994 and Bellingham et al, 1994). This paper uses this average data when calculating the amount of electricity recovered. The electricity generated will displace emissions from old coal-fired power stations, and this study gives credit for these.
This probably wasn't even true in 1993 (the most recent year for which the Williams and Bellingham papers are likely to have had data). As I have mentioned before, I ran (until recently) the company that sold many of the flarestacks used on British landfills, so I know that a lot more flares went into landfills before 1993 than is usually assumed in government studies aiming to maximize the claimed reductions in landfill-gas emissions since then (which undermines the Government's claims that we are on target to meet our Kyoto obligations, but that is another story).
Whatever the case in 1993, nowadays this is absurd. The usual figure quoted for the capture-rate of methane from landfills over the lifetime of a modern, engineered landfill is about 85%. This is the figure used as standard in the government-approved model (GasSim) for estimating emissions from landfills. During the period when the gas is contained (i.e. after the phase has been "capped") and being converted (i.e. until the gas quality falls so low that it can no longer be flared), the capture rate is probably close to 100% in modern, engineered landfills. The 85% represents an allowance for emissions from the uncapped phase being tipped at any one time (the usual source of any odour), and slow seepage of the tail-end gas once it is no longer possible to flare it, by which time you are talking low volumes and low percentages of methane. Given sensible incentives, it would be possible to further reduce these emissions so that the overall capture-rate was over 90%, but let's take 85% as a reasonable average. Of that, provided that sensible incentives are maintained for its utilisation, the vast majority will be converted to electricity.
The impact on the LCA of assuming 19% capture, of which 6% utilisation, rather than the current figures of 85% capture of which perhaps 80% utilisation, is enormous. Methane (CH4) has a Global Warming Potential 23 times higher than carbon dioxide (CO2). If you assume that most of the carbohydrates in your waste are converted into landfill gas (roughly 50:50 CH4 and CO2), that most of that gas gets out, and that very little of it is used to displace fossil-fired generation, the comparison between landfill and any other form of waste disposal will be a no-brainer. Of course landfill is the worst technique if it's simply belching methane into the sky.
But this is bollocks. Methane isn't belching out of modern landfills - it is being captured and used to provide the largest single source of new renewable electricity in the country. Last year, landfill-gas generators produced nearly 4 TWh of renewable electricity. Onshore wind projects produced 2.8 TWh, offshore wind less than 0.7 TWh, while co-firing of biomass with coal, and refurbished hydro plants produced almost 2 TWh each.
The authors of the paper carefully ensured that it was not possible to trace their calculations from their assumptions to their conclusions. So it is not possible to reconstruct their calculations with more accurate assumptions. But even where they state their results, without showing how they were calculated, further errors intrude. On p.17, it is assumed that 13,000 grammes of methane are released per tonne of plastic landfilled (around a quarter of the methane emission-rate of paper). Ah yes, that famous putrescible plastic. This is such a beginner's error, that you have to wonder whether the authors had ever set foot on a landfill, or spoken to a waste-disposal operator.
And there is more. Landfilling of aluminium is assumed on the same page to produce 206.5 kilogrammes of methane per tonne of aluminium. Biodegradeable aluminium joins biodegradeable plastics in these academics' parallel universe. And thanks to what I can only assume is a labelling error, it is magnified by a factor of one thousand - not 206.5 g/t, but 206.5 kg/t in their scheme, or four times as much methane as is released from landfilling paper.
This study is so wrong that it isn't even in the right ballpark and so obfuscated that it is impossible to correct. And yet it is on studies like this that recycle-nuts like Dr Dicks rely to justify their brain-washed mantra of "reduce, reuse, recycle". That may be the right approach, in some circumstances, but where appropriate (as indicated by relative costs), not as a rule. The current EU Directives on waste disposal, the Government's dirigiste waste strategy (in compliance with the EU), and councils' complex collection schemes (in compliance with the Government's strategy), are based on nothing more than incompetence and distortion.