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What risks does society want to manage? Well let’s get the facts before we jump to conclusions

The initial response to my blog, Is LNG the solution for our more complex world? which was originally a Lloyd’s List article seems to miss the point.

There are very clearly, as I state, considerable local benefits in using LNG as a marine fuel. Other observers (journalists?) may be sceptical as to the benefits of using LNG as a marine fuel – we are not. As I wrote, LNG is very suitable for certain applications such as ferries in ECAs. But the claims of those marketing LNG as a solution to greenhouse gas emissions requires caution, it would seem. It may be part of a solution to GHGs. But on one level we must accept that LNG is just another fossil fuel.

I have not read the TNO research referred to but our reading of the referenced Chalmers report conclusions is that the authors are rather more equivocal than the response to my blog suggests.

The Chalmers authors wrote: ‘LNG as marine fuel has a global warming potential from a life cycle perspective of the same order of magnitude as today’s marine fuels.’ And the report adds that there are still areas where relevant information is limited or non-existent: ‘There are still areas where information is limited or even non existent. Two important knowledge gaps have been identified: fugitive emissions of methane and volatile organic compounds during distribution and the performance of gas engines during operating conditions.’

That’s not to say that technology and regulation can’t help assure 20-25% CO2 reduction benefits from LNG combustion (before a life cycle analysis). But as it seems I must repeat, even if the most optimistic claims for LNG are true and even if the lifecycle impact is less than existing fuels we will not realise overall reductions in GHG emissions – in the face of growing demand for energy we are probably going to have to do something more radical than just switch fossil fuels.

However, much of the excitement around LNG’s prospects devolves from the prospect of abundant, cheap, gas as a result of gas from new reserves of ‘unconventional’ gas exploited through technologies such as fracking. And there are certainly legitimate question-marks over lifecycle GHG emissions from unconventional gas reserves that have been raised by academics (and some of which has been reported by leading newspapers).

For example, Cornell University’s Howarth, Santoro and Ingraffea’s work, Methane and the greenhouse-gas footprint of natural gas from shale formations (March 2011) is an interesting read.

The authors emphasise the importance of methane emissions, or rather not under-estimating methane: ‘Given the importance of methane in global warming, these emissions deserve far greater study than has occurred in the past. We urge both more direct measurements and refined accounting to better quantify lost and unaccounted for gas.’

‘The large GHG footprint of shale gas undercuts the logic of its use as a bridging fuel over coming decades, if the goal is to reduce global warming. We do not intend that our study be used to justify the continued use of either oil or coal, but rather to demonstrate that substituting shale gas for these other fossil fuels may not have the desired effect of mitigating climate warming.’

And of course we have read DNV’s recent technology outlook with interest which states, ‘Although natural gas combustion can reduce CO2 emissions by up to 25 % compared with bunker oil, emissions of unburned methane represent a problem. Methane is 21 times more potent greenhouse gas (GHG) than CO2. Depending on engine type, the change in CO2- equivalent emissions range from a reduction of 20 % up to a net increase.’  (Presumably this excludes life cycle analysis and opens the door – at least a little – to legitimate concerns that LNG does not [significantly] reduce CO2 emissions on a like-for-like basis with other fossil fuels).

As I say in the Lloyd’s List article – and this is the main point – there is a lot more work to be done in addressing the question as to whether the replacement of HFO by LNG in marine bunkers really can significantly help address the problem of greenhouse gas emissions as well as local air quality issues.

It’s not about spin or perception. It’s about establishing the facts and making choices based on real performance (not manufacturers’ or marketers claims) and deciding what to do about global warming. We need an utterly impartial approach to the question of technical and operational measures, including future fuels, and what to do about the big (and much more difficult to manage than local emissions) issue of managing greenhouse gas emissions while we still expect world trade and shipping to continue to grow massively.

As Yvo de Boer said at the Sustainable Shipping Awards dinner last week, ‘We as an industry can choose’ what we want to do about GHG emissions and other environmental issues. But it is best we do so based on the best factual information and advice available.

For more information on LNG as a Fuel go to www.lr.org/lng

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