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Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
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    •  
      CommentAuthorfostertom
    • CommentTimeNov 19th 2021 edited
     
    https://www.theguardian.com/environment/2021/nov/19/uk-must-boost-recycling-of-materials-for-green-industries-report-says
    refers to
    https://green-alliance.org.uk/resources/Critical_point_securing_the_raw_materials_needed.pdf

    Dustin H in The Graduate got career advice from one of his parents' ghastly drunken middle-aged friends - 'Plastics my boy, plastics'. Me, I feel like advising 'youngsters' to get trained for a career in Recycling -
    not today's lo-grade municipal scavenging of 40% (if lucky) of packaging plastics to down-cycle into mud-coloured fencing and decking planks -
    but future hi-tec near-100% capture of almost everything, involving massive use of green energy to break chemical bonds (e.g. in electrolising) to up-cycle back into virgin feedstock. Rare elements yes, but also hydrocarbon/plastics, common metals, maybe even minerals locked into construction materials.

    This report makes the case for such near-100% recapture of rare elements, in massive demand for electrics and electronics incl batteries, presently causing 'rape of the earth' mining and social disaster around the world. This surely is an almost 'shovel-ready' hi-tec industry that every nation, developed and developing, could rapidly roll out, with some (but not huge, because automated) empoyment benefit and great value-added/cost-saved to the economy.

    I am puzzled though, in this report, that national energy saving especially housing insulation, seems a vital part of their theme. Of course yes, energy saving is right, but I'm missing how it fits with the main re-capture element - I don't see it spelt out.

    Is it that energy saving will lead to smaller demand for power generation, hence lower demand for rare elements? I don't think so - generating (and storage) capacity will proceed at high speed regardless.

    Is it that existing-purposes energy saving will free up generating capacity for the required input into breaking chemical bonds (e.g. in electrolising) to up-cycle back into virgin feedstock? Yes, but that energy input isn't mentioned in this report - they seem to think it's just a matter of sorting the waste stream.

    Am I missing something?
    • CommentAuthorJohn Walsh
    • CommentTimeNov 20th 2021
     
    Posted By: fostertomIs it that energy saving will lead to smaller demand for power generation, hence lower demand for rare elements?


    Agree it's not clearly spelt out - which is a big problem given their ambition. From the Green Alliance doc:

    "Our analysis shows that the amount of critical raw materials required could be sharply reduced by cutting energy demand and improving resource efficiency." (p4)

    "[there is a need to] support design innovations that reduce the need for critical raw materials in low carbon technologies." (p5)

    "By cutting energy use across buildings, transport, industry and food, cumulative demand for lithium and cobalt could be reduced by 55 per cent in 2030." (p12)

    So, yes, it is there opinion that lower demand for power generation is key to reducing use of rare elements. It seems to make sense. Hasn't there been a reduction in electricity use in the UK over the last 10-20 years? Wouldn't it make sense to factor in rare element consumption as another reason for accelerating decline in power consumption? But, are they streets ahead of where most people are in progressive climate/ecology/societal thinking?
    • CommentAuthorSimonD
    • CommentTimeNov 20th 2021 edited
     
    Posted By: John WalshBut, are they streets ahead of where most people are in progressive climate/ecology/societal thinking?


    Streets ahead of the mainstream, yes, but following some fairly established thinking in areas still largely left in the shadows.

    I keep on about how it's consumption together within environmental destruction that are the biggest problems we face rather than carbon emissions per se and those proponents of renewable energy don't seem to realise than even with renewable energy there must be a significant reduction in energy and resource consumption. This is also happening here on GBF where it's suggested that the reduction in carbon intensity means we don't need to put so much effort into improving the energy performance of homes.

    But we're many decades behind some of the leading thinkers in the area. Here's a qoute from Donella Meadows and others report to the club of Rome from 1972 based on the MIT's System Dynamics modelling:

    "1. If the present growth trends in world population, industrialization, pollution, food production, and
    resource depletion continue unchanged, the limits to growth on this planet will be reached sometime
    within the next one hundred years. The most probable result will be a rather sudden and uncontrollable
    decline in both population and industrial capacity.

    2. It is possible to alter these growth trends and to establish a condition of ecological and economic
    stability that is sustainable far into the future. The state of global equilibrium could be designed so that
    the basic material needs of each person on earth are satisfied and each person has an equal opportunity to
    realize his individual human potential.

    If the world's people decide to strive for this second outcome rather than the first, the sooner they begin
    working to attain it, the greater will be their chances of success."

    In this paper the primary risk of system collapse lies in non-renewable resource depletion.

    Link to the paper which seems today to be rather prescient https://web.ics.purdue.edu/~wggray/Teaching/His300/Illustrations/Limits-to-Growth.pdf
    •  
      CommentAuthordjh
    • CommentTimeNov 20th 2021
     
    Posted By: SimonDBut we're many decades behind some of the leading thinkers in the area. Here's a qoute from Donella Meadows and others report to the club of Rome from 1972 based on the MIT's System Dynamics modelling

    I agree with you that reducing use of resources is vital, including too-cheap-to-meter-fully-renewable-power if it ever comes to pass, and as you say unlike the apparent attitude of some on here. But there's a danger in quoting such old papers, however right they may still be, in that they are based on an old evidence base that needs to be updated and the conclusions revalidated before you can rely on it. For example in this case, population projections have changed very significantly from then until now.
  1.  
    Mining is undoubtedly problematic for electric cars and storage batteries, and opponents are using that as a stick against them, but that shouldn't be an option for opponents of renewable electricity.

    The wind turbine manufacturers are well aware of the downsides of rare earths in permanent-magnet direct-drive generators, so they are protecting themselves against supply or pricing problems by keeping up development of earlier and alternative technologies.

    They can use high speed (geared) drives which use smaller generators with smaller permanent magnets, which are also lighter than direct drive generators and so are being used for the very tall 10MW range offshore turbines. Or they can use doubly-fed induction generators without permanent magnets, which are common for onshore (<3MW) turbines. Superconducting generators at sensible temperatures are moving into demonstration at 3MW+ scale.

    Given that the technologies exist for renewable generators without rare earths, their customers (governments and power companies) perhaps need to insist/pay for them to be used now, rather than saved as insurance against supply problems later.

    Larger generators (hydro, tidal, nuclear) do not use permanent magnets.


    Removal of rare earths from the grid supply, should obvs be 'as well as' conservation of primary energy (hence carbon) with heatpumps and insulation, not 'instead of'....


    Edit: Interesting article about eliminating silver from PV panels, though still very early days https://www.bloomberg.com/news/articles/2021-09-09/sundrive-solar-startup-beats-china-s-giant-manufacturers-in-efficiency-test
    • CommentAuthorSimonD
    • CommentTimeNov 21st 2021 edited
     
    Posted By: djhBut there's a danger in quoting such old papers, however right they may still be, in that they are based on an old evidence base that needs to be updated and the conclusions revalidated before you can rely on it. For example in this case, population projections have changed very significantly from then until now.


    Yes totally agree. It should be taken in the spirit of the post, merely to illustrate history of relavant thinking in the area. It was also based on early systems dynamics models. Hopefully readers will only hold it fairly lightly in the context rather than rely on it :smile:
  2.  
    Sorry if getting off topic, but if anyone is interested and doesn't already have it, the official version of 'The Limits to Growth' is still available from the late author's website

    https://www.donellameadows.org/wp-content/userfiles/limits-to-growth-digital-scan-version.pdf

    The authors never intended the outputs of their economic model to be taken literally, the value comes from altering the inputs and seeing how they affect the outputs. A few years ago I came across a spreadsheet implementation of their economic model, which was fun to play with, but I've lost the link - anyone got it?

    As DJH mentioned and as the book discusses, they had to make an estimate of how birth rates would respond to increasing wealth, and based on then-available evidence they assumed fertility would always remain above the 'replacement' rate of ~2 children per couple. This steered all of their models into an exponential population growth, until a Malthusian collapse was predicted due to food shortages.

    However, the birth rates in even moderately-wealthy countries (China) have turned out to be well below 'replacement', such that population is already declining in some wealthy countries, and others such as UK are fortunate to still have immigration to replace the working population.

    https://www.bbc.com/news/health-53409521 "'Jaw-dropping' global crash in children being born"

    So the predicted population declines are locked-in to happen, but fortunately for reasons of affluence rather than starvation, after the remaining lifetime passes of the 'peak humans' generation.

    As the authors discussed, these long-term models are very difficult to adapt to small changes in inputs, such as people's ability to invent better ways of producing food or energy when the limitations of the previous methods become overwhelming. They illustrated this with the possibility that nuclear power might replace fossil fuels causing nuclear waste, but they were working a little too early to include the rise of renewable electricity.

    "If man's energy needs are someday supplied by nuclear
    power instead of fossil fuels, this increase in atmospheric C02
    will eventually cease, one hopes before it has had any measur-
    able ecological or climatological effect."
    • CommentAuthorSimonD
    • CommentTimeNov 21st 2021
     
    Posted By: WillInAberdeenSorry if getting off topic


    Off topic is really useful but I think what you say does pertain to the conversation, in light of which, I think it's useful to focus on the purpose of The Limits Growth which is encapsulated in this:

    "We hope that The Limits to Growth will command critical
    attention and spark debate in all societies. We hope that it will
    encourage each reader to think through the consequences of
    continuing to equate growth with progress. And we hope
    that it will lead thoughtful men and women in all fields of
    endeavor to consider the need for concerted action now if we
    are to preserve the habitability of this planet for ourselves
    and our children"

    As for the population growth element, this is seen as a key part of the model, as is alternative energy where is it discussed in the following nuanced light:

    "Some experts believe that abundant energy resources will en-
    able mankind to discover and utilize otherwise inaccessible
    materials (in the sea bed, for example); to process poorer ores,
    even down to common rock; and to recycle solid waste and
    reclaim the metals it contains. Although this is a common be-
    lief, it is by no means a universal one, as the following quota-
    tion by geologist Thomas Lovering indicates.
    Cheaper energy, in fact, would little reduce the total costs ( chidly
    capital and labor) required for mining and processing rock. The ~nor­
    mous quantities of unusable waste produced for each unit of metal in
    ordinary granite (in a racio of at least 2,000 to 1) are more easily dis-
    posed of on a blueprint than in the field .... To recover minerals
    sought, the rock must be shattered by explosives, drilled for input and
    recovery wells, and flooded with solutions containing special extractive
    chemicals. Provision must then be made to avoid the loss of solutions
    and the consequent contamination of groundwater and surface water.
    These operations will not be obviated by nuclear power."

    ""Unlimited" resources thus do not appear to be the key to
    sustaining growth in the world system. Apparently the eco-
    nomic impetus such resource availability provides must be ac-
    companied by curbs on pollution if a collapse of the world
    system is to be avoided. "

    Part of this, which mustn't be forgotten is that it is an excercise in modelling system dynamics and therefore considering the multitude of factors involved in the behaviour of a system. In this light, it is impossible for one part of the system not to affect, through positive or negative loops, other parts of the system. What they were looking for in their modelling exercise was:

    We are searching for a model output that
    represents a world system that is:
    1. sustainable without sudden and uncontrollable collapse; and
    2. capable of satisfying the basic material requirements of all
    of its people.
    Now let us see what policies will bring about such behavior
    in the world model.

    To illustrate the complexity:

    "Apparently, if we want a stable system, it is not desirable
    to let even one of the two critical positive feedback loops generate uncontrolled growth. Stabilizing population alone is not sufficient to prevent overshoot and collapse; a similar run with
    constant capital and rising population shows that stabilizing capital alone is also not sufficient."

    I do agree that the purpose of the exercise was not to take its outputs literally, but to better understand the relationships between critical factors involved within the model and how they relate to each other dynamically in a way that positively or negatively affects the environment on a global scale.

    If anything, it has indeed helped to spark debate :smile:
    •  
      CommentAuthorfostertom
    • CommentTimeNov 22nd 2021 edited
     
    It's good to see a revival of awareness of Limits to Growth, which was largely forgotten for decades. As said above, not to use as scientific base today, but to highlight how hugely environmental awareness has changed for the better, while other things got far worse than anticipated, and some, like the persistence of market capitalism, 'scientific' (not!) Economics, interest-bearing FIAT currency etc, haven't budged at all.
  3.  
    The TLTG conclusions did make sense from the viewpoint of the 70s - it seemed outrageous when they raised the idea of reducing fertility rates from >3 children per couple down to the replacement rate of ~2 , in search of a 'stable' population.

    But the fertility rate has actually fallen to 1.53 in the EU, which is far below any inputs they modelled, and simply cannot produce the exponential growth cycles they were concerned about - instead it means an exponential decline. In the 70s this was seen as a catastrophic 'population collapse', but actually not many people seem to have noticed yet!

    Is unknown whether the fertility rate will recover in the future, so any such forecasts are close to meaningless.


    The other big 70s perspective was that economic growth must be based on digging non-renewable stuff out of rocks (even from granite, in the passage quoted above).

    Economic growth these days is overwhelmingly in services, from human resources. There is still too much residual rock-digging, whether for coal or neodymium, but it is feasible to replace those with renewable energy and induction-generators - if we push hard enough!

    When there are limiting resources, that human ability to switch over to more sustainable alternatives, is itself a powerful feedback loop. Population forecasters have always found this loop difficult to include in their models - as the book discusses! :bigsmile:
    • CommentAuthorEd Davies
    • CommentTimeNov 22nd 2021
     
    Tom Murphy's “Do The Math” blog is of some relevance here. I used to read it when it was active years ago then he stopped posting and I've only just discovered he's started again.

    https://dothemath.ucsd.edu/

    He's also written a textbook “Energy and Human Ambitions on a Finite Planet” which I'm just starting to read:

    https://escholarship.org/uc/energy_ambitions
    • CommentAuthorSimonD
    • CommentTimeNov 22nd 2021 edited
     
    Posted By: Ed DaviesTom Murphy's “Do The Math” blog is of some relevance here. I used to read it when it was active years ago then he stopped posting and I've only just discovered he's started again.

    https://dothemath.ucsd.edu/" rel="nofollow" >https://dothemath.ucsd.edu/

    He's also written a textbook “Energy and Human Ambitions on a Finite Planet” which I'm just starting to read:

    https://escholarship.org/uc/energy_ambitions" rel="nofollow" >https://escholarship.org/uc/energy_ambitions


    Brilliant. Another great link for reading, thanks. It distracted me so much I started immediately reading the book only to tell myself off because I've got work I have to do! :bigsmile:

    Edit:

    I've just read the tentative Foundational Principles of the Planetary Limits Academic Network (https://planetarylimits.net/) part founded by Tom Murphy, all of which resonated very much with me:

    "
    Humans are a part of nature, not apart from nature.
    Non-renewable materials cannot be harvested indefinitely on a finite planet.
    The ability of Earth’s ecosystems to assimilate pollution without consequences is finite.
    Energy throughput is essential to all human activities, including the economy.
    Technology is a tool for deploying, not creating energy.
    Fossil fuel combustion is the primary cause of ongoing global climate change.
    Exponential growth, whether of physical or economic form, must eventually cease.
    Today’s choices can simultaneously create problems for and deprive resources from future generations.
    Human behavior is consciously and unconsciously shaped by mental models of culture that, while mutable, impose barriers to change.
    Apparent success for a few generations during a massive draw-down of finite resources says little about chances for long-term success.

    "
  4.  
    Posted By: WillInAberdeenthe fertility rate has actually fallen to 1.53 in the EU, which is far below any inputs they modelled, and simply cannot produce the exponential growth cycles they were concerned about - instead it means an exponential decline....
    When there are limiting resources, that human ability to switch over to more sustainable alternatives, is itself a powerful feedback loop. Population forecasters have always found this loop difficult to include in their models
    Posted By: Ed Daviesa textbook “Energy and Human Ambitions on a Finite Planet”


    It's been bothering me that so much of the "environmental" community is worrying about an exponential population growth, whereas the "population dynamics" people are all worried about collapse in fertility. Been trying to understand why it is they don't agree with each other.

    It seems that 20thCentury population models were along the lines of the 'logistic equation', explained in Tom Murphy's well written textbook

    Population (P) growth = dP/dt = rP - rP²/Q

    where r is the fertility rate = (births per parent, so half the usually quoted births per couple value) and
    Q is the maximum population that the natural resources can support.

    This logistic equation predicts an exponential population growth, slowing down only when resource competition causes enough extra deaths to balance out the births. So after that the population becomes unchanging, with most individuals dying of hunger in middle age. That's what scared the 20thC forecasters.

    This doesn't fit the observed reality that most animal populations are not unchanging, they can decline even without mass die-offs from resource competition. In fact now the number of children is lower than the number of their parents' generation in most countries, and especially in all the resource-rich countries where most people live well-fed into old age!

    So by using simple equations, we ended up with predictions that haven't worked, the world is more complex than we thought.


    The population researchers seem to think the limitations with the logistic equation are:
    -it assumes all the population are actively reproducing (but most of us humans have got too old for that sort of thing)
    -it assumes that the fertility rate stays constant (but fertility has halved from the boomers to the millennials)
    -it assumes natural resources will be unchanging (but we have massively damaged many natural resources, and developed new resources such as renewables)
    -it predicts that the population can never overshoot the natural resources (ditto)
    -it assumes individuals will compete for scare natural resources, rather than cooperate in tribes to develop new resources (ditto)


    To fix these, people have tried altered forms of the logistic equation, where fertility and resources are allowed to vary over time, and with time delay feedback effects.

    This one seems quite popular, it predicts population can grow in steps, oscillate, switch between different stable states, expand, collapse or stay unchanging. Tricky bit is to work out which!

    https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2224539
      Screenshot_20211126-151350.png
    • CommentAuthorSimonD
    • CommentTime4 days ago
     
    Posted By: WillInAberdeen

    This one seems quite popular, it predicts population can grow in steps, oscillate, switch between different stable states, expand, collapse or stay unchanging. Tricky bit is to work out which!

    https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2224539
      http:///newforum/extensions/InlineImages/image.php?AttachmentID=8106" alt="Screenshot_20211126-151350.png" >


    I think you're always going to get a mixture of all those across the global population, albeit with some more consistent phases each way. There's the typical complexity that in many instances you'll see simultaneous competition and cooperation rather than binary one prevails over the other.

    I took a look at the paper and models and was intrigued I couldn't find anything about the assumptions regarding the underlying meanings of competition/cooperation, other than 'individuals competing for resources,' for example. That always troubles me. There must be some social theory behind the equations because we know that society, culture, politics, and ideology (e.g.neoliberalism) play their significant hand in population growth and decline, not just physical resources, births and deaths. Given the mention of 'individuals competing for resources' it does seem to be a neoliberal view assuming individualism as a driver but that is only currently socially dominant in primarily western countries (well, it's assumed to be dominant but that's another discussion entirely) and thus doesn't account for more social cultural perspectives such as those across south east Asia.

    It's certainly a model that shows promise and matches some of the real world historical trends, which is always helpful. :smile:
  5.  
    AIUI,
    -the 19thCentury models accounted only for reproduction (Malthus et al) and predicted exponential population growth;

    -the early 20thCentury models accounted for reproduction and competition (TLTG) and predicted exponential growth restrained by starvation;

    - these newer models account for reproduction, competition and cooperation.

    They are for modelling animal/plant populations (Murphy's textbook uses the example of modelling the deer population in a forest) so I don't think there's a generalised social theory of what "competition" or "cooperation" means. That would be specific to the species you are modelling.

    So for example, the deer might compete with each other for food in the winter, but they might also cooperate by gathering in a herd to resist predators, and passing on knowledge about where to find shelter or water. Red deer do that more than Roe deer so each might thrive in different environments. Competition might work better than cooperation for the Roes in woodland where lone individuals can hide from predators; the Reds might need to work as a herd on open moorland.

    I don't think they depend on a world view such as neoliberalism or north/south cultural generalisations. If we are exchanging knowledge on GBF, that would presumably count as a teeny nudge up in the cooperation coefficient in the model!

    So the previous theories predicted that humans are doomed to a population explosion followed by an environmental collapse, but the more nuanced theories allow the possibility that humans can use alternative resources in more sustainable ways. That's encouraging!
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