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Green Building Bible, Fourth Edition
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    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2021
     
    https://www.theguardian.com/environment/2021/aug/12/uk-replace-fossil-gas-blue-hydrogen-backfire-emissions

    "“fugitive” emissions from producing hydrogen could eclipse those associated with extracting and burning gas when multiplied by the amount of gas required to make an equivalent amount of energy from hydrogen"

    “This is a warning signal to governments that the only ‘clean’ hydrogen they should invest public funds in is truly net zero, green hydrogen made from wind and solar energy,”
    •  
      CommentAuthordjh
    • CommentTimeAug 21st 2021 edited
     
    Here's an interesting analysis that tends to reinforce the grauniad article, making an alternative analysis of the data:

    https://energy-surprises.blogspot.com/2021/08/comparing-blue-hydrogen-with-natural.html

    AFAICT hydrogen is a bad idea and I don't understand why it is being promoted. (except by vested interests, I mean)
  1.  
    The analysis quoted in the Graun is skewed fairly heavily against hydrogen-from-methane, as was fairly obvious from the paper, and as is unpicked in the blog.

    It claimed to be a lifecycle analysis, but most unusually it only considered a 'lifecycle' of 20 years. It compares fugitive methane (which has a lifetime of a decade or so) against combustion CO2 which will persist for 10,000years+. So by only considering the damage done during the first 20 years, it compares all of the damage from methane, against a tiny fraction of the damage that the CO2 will go on to do.

    I can't think of any charitable explanation for why this was done. The newspaper might have printed it as click bait, or as a stick with which to hit their readers' political opponents, or because they lack the knowledgeable journalists who could smell the trick, or all of those.

    During the early phase of covid, many people were rightly critical of those who spread dubious advice for those kinds of reasons, but it seems it is acceptable to spread it about climate change, including by quoting it on here.

    The blog reworked the analysis and suggests that "Blue hydrogen is now only one third the emissions of natural gas". So much better than fossil fuels, but not zero-carbon.

    The overall conclusion that green hydrogen is preferable to blue hydrogen, is like saying that gold is preferable to lead. Yes it obviously is, but as there is no prospect of having gigawatts of 'spare renewable electricity' anytime soon with which to make the green hydrogen, then we might have to make do with blue hydrogen and use it wisely and sparingly to displace heavy industrial fuels, so not for burning for space heating.
    •  
      CommentAuthordjh
    • CommentTimeAug 21st 2021 edited
     
    Posted By: WillInAberdeenmost unusually it only considered a 'lifecycle' of 20 years

    That's because (a) twenty years is the most important timescale, rather than 100 years and (b) the lifetime of CH4 in the atmosphere is better measured in that timescale. Charity has nothing to do with it; the welfare of the planet absolutely does.

    The blog reworked the analysis and suggests that "Blue hydrogen is now only one third the emissions of natural gas".

    No it doesn't.That's on the basis of 100 year equivalent, which is irrelevant.

    Yes it is, but as there is no prospect of having gigawatts of 'spare renewable electricity' anytime soon with which to make the green hydrogen, then we might have to make do with blue hydrogen and use it wisely and sparingly to displace heavy industrial fuels, so not for burning for space heating.

    What she actually says is :

    "My conclusion is that producing blue hydrogen production at scale is going to have the opposite effect that we are trying to achieve. I am more convinced than ever that we have to stick with cleaner methods such as electrolysis. This means we will have less of it and we must use it wisely."

    i.e. She says we should not make do with blue hydrogen because it will make things worse instead of better.

    We must try harder to generate enough green hydrogen for those cases where it is essential, and find ways to use something else (renewably-sourced) for those case where it is not absolutely required.
  2.  
    So please explain, why is it that damage from CH4 in the next 20 years (IE affecting you and me) is more important than the much greater damage that will inescapably continue to be done by our CO2 in 100 or 1000 years from now (IE not affecting you and me)?

    I still can't think of any charitable explanation for why that could be true. It smells like it's nothing to do with the welfare of the planet and everything to do with 'I'm alright Jack'. Or maybe for the 'editorial policy' reasons I mentioned above.
    • CommentAuthorjms452
    • CommentTimeAug 22nd 2021
     
    Posted By: WillInAberdeenSo please explain, why is it that damage from CH4 in the next 20 years (IE affecting you and me) is more important than the much greater damage that will inescapably continue to be done by our CO2 in 100 or 1000 years from now (IE not affecting you and me)?


    20, 50 and 100 years are all commonly used so the paper isn't doing anything unusual (although it is on the lower end) - Which to use depends on the timeframe we estimate the climate response is to become non-linear.
    Basically it comes down to tipping points - If we pass (what I'll dramatically call) a point of no return we've passed it.

    From an accounting perspective we are given the 'astronomical' costs (of climate action) over time frames of 20 or 30 years all the time (with little mention that after that we'll be receiving dividends). Stretching out the time frame we look at the damage to 50 or 100 years seems like an accounting trick to incentivise inaction to me.
    • CommentAuthorCliff Pope
    • CommentTimeAug 24th 2021
     
    <blockquote>

    Stretching out the time frame we look at the damage to 50 or 100 years seems like an accounting trick to incentivise inaction to me.</blockquote>

    A bit like worrying over the scale of the National Debt. It's been horrendous for centuries. But as it's impossible to reduce it we might as well go on letting it increase - it doesn't seem to matter.
    • CommentAuthorSimonD
    • CommentTimeAug 25th 2021
     
    Posted By: jms452

    From an accounting perspective we are given the 'astronomical' costs (of climate action) over time frames of 20 or 30 years all the time (with little mention that after that we'll be receiving dividends). Stretching out the time frame we look at the damage to 50 or 100 years seems like an accounting trick to incentivise inaction to me.


    TBH I think it's less an accounting trick, more of a system inertia. Historically the problem with investment in renewables, and especially large projects like hydro, has been discount rates which to obviously relate to time frame. Much of the traditional discount rates use a period of 25-50 years for financing whereas large renewable projects pay dividends for a lot longer. However there have been questions about wind/solar and how to model those, particularly when it comes to costing decommissioing as these cost are so far only estimate on loose predictions.

    As costs of RE are nearing parity with fossils there's more interest in this from private investors and as such Grant Thornton has recently published a global study to help investors understand geographical discount rates.

    There are future problems about to hit us on this front as a whole generation of solar panels is about to be pulled out and replaced. Currently the cost of chucking it all in landfill is about 1/10 of the cost of recycling.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 25th 2021 edited
     
    The downside of blue hydrogen seems to be “fugitive” emissions from continued methane production, transport and production of the hydrogen (i.e. more of it than if blue hydrogen wasn't creating demand for methane).

    In first 20yrs, that methane has 20x (is it?) the GHG efect of CO2. After that (crudely) it becomes mere CO2. So add the 20yr GHG effect of this study to yrs 21-100 of other studies of CO2 GHG effect. Seems to me, doing that can only add to the 100yr GHG effect of the blue hydrogen route.

    Making this a 20yr study in fact under-estimates GHG effect compared to making it a 100yr study.
    • CommentAuthorSimonD
    • CommentTimeAug 25th 2021
     
    Posted By: fostertomThe downside of blue hydrogen seems to be “fugitive” emissions from continued methane production, transport and production of the hydrogen (i.e. more of it than if blue hydrogen wasn't creating demand for methane).

    In first 20yrs, that methane has 20x (is it?) the GHG efect of CO2. After that (crudely) it becomes mere CO2. So add the 20yr GHG effect of this study to yrs 21-100 of other studies of CO2 GHG effect. Seems to me, doing that can only add to the 100yr GHG effect of the blue hydrogen route.

    Making this a 20yr study in fact under-estimates GHG effect compared to making it a 100yr study.


    I think it's worse at 28x CO2.

    Having only read the G. article, and not the actual study, it pains me to see a life-cycle study only looking at the life-cycle of CH4 rather than the cradle to grave of CH4 which would properly account for the remnant CO2 in the atmosphere. Lets face it, most properly conducted life-cycle assessment would do so, although life-cycle assessments I've read about gas boilers and heat pumps, for example, don't appear to explicity consider such things as fugitive emissions as part of global warming potential. However, as seems to have become popular, they'll often only look at GHG effects rather than wider total environmental impact, which is problematic.

    I must look into their methodology.

    I do keep hoping to see the development and use of more systemic methodologies.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 25th 2021
     
    Not sure what cradle or grave mean, for elements of chemicals, which aren't created or destroyed. If there's a recurring cycle, you can look at a complete cycle. If it's a merging/mixing, it's hard to pick a definitive 'lifetime'.
    • CommentAuthorSimonD
    • CommentTimeAug 26th 2021
     
    Posted By: fostertomNot sure what cradle or grave mean, for elements of chemicals, which aren't created or destroyed. If there's a recurring cycle, you can look at a complete cycle. If it's a merging/mixing, it's hard to pick a definitive 'lifetime'.


    I think it's fundamentally a question of methodology here. Life-cycle Assessment as a methodology was developed to quantify environmental damage caused by products or services, or processes (sorry if I'm teaching to suck eggs?). If we consider the process of extracting, distributing and processing methane, then there is a chemical reaction that is a natural part of the life-cycle of that methane - i.e. it breaks down into CO2 - thus if that methane was not released by the process, this CO2 would not be released into the atmosphere as a consequence of that process. Even if you consider this process of breaking down into CO2 a secondary effect, it would be an incomplete, or too narrow, LCA of the methane process, as there is a another environmental damage caused (or if considered weak, correlated) as a result, one which one could argue may be worse over the long-term due to the extend life span of CO2 in the atmosphere.

    From what I'm able to read, however, the study referred to isn't a life-cycle assessment as such as I can only find reference to global warming potential and ghg emissions whereas a LCA would include other environmental damage.

    There is also one rather major omission which is that the estimate for fugitive emissions from natural gas production are probably rather low as they only consider direct leakage from the process itself. There is significant additional CH4 leakage caused by wider production processes, such as accidents and uncontolled leakage from decommissioned sites etc. that don't make it onto the official emissions figures for Europe, or the US. I can just imagine what it might be like in other parts of the world. For instance:

    "For example, a recent paper published in Nature examined historical ice cores and found that prior to 1950, natural geological sources of methane were much smaller (around 1-2 Mt/year) than has been generally assumed (between 40-60 Mt/year). As a result, the paper concluded that the aggregate level of methane emissions from fossil fuel production and consumption in recent years has been closer to 175 Mt/year rather than 120 Mt/year (as in IEA estimates).

    What is clear is that the concentration of methane in the atmosphere has risen steadily since the mid-2000s. However, the cause of this increase is the subject of an active debate in the scientific community. Possible explanations include:

    The natural mechanisms that break down methane in the atmosphere are becoming weaker
    There has been a rise in biogenic sources of methane (e.g. from agriculture or waste)
    There has been a rise in natural sources of emissions (e.g. wetlands and other flood zones)
    There has been a rise in emissions from the extraction of fossil fuels"

    https://www.iea.org/reports/methane-tracker-2020/methane-from-oil-gas

    Nevertheless, the study is at least useful in adding to and reshaping the debate, and hopefully the direction of a future hydrogen strategy.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 26th 2021 edited
     
    That's all helpful.

    What we really need to know, is a comparison between the GHG (plus all the other?) impacts of:

    1. substituting blue hydrogen for some existing fossil burning (releasing no GHG in use, but releasing some CH4 in production, eventually becoming CO2);

    2. substiuting green hydrogen for some existing fossil burning (in theory releasing no GHG);

    3. carrying on fossil burning (releasing lots of CO2 in use and some CH4 in production (no doubt similar quantity to 1), eventually becoming CO2).

    The Guardian article suggests that 1. in actually worse than 3.

    Example of 2. https://boingboing.net/2021/08/26/a-swedish-company-figured-out-how-to-decarbonize-steel.html
    Hydro electric of course. Used for one of those purposes (like powering trucks, producing cement) which are hard to wean off fossil - unlike wasting it on 'easy' domestic heat (or its inverse, house insulation)
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