Is Model Engineering “green”?

[Michael GilliganParticipant @michaelgilligan61133]

Thanks for replying, Dave

Unfortunately, I remain very suspicious of ‘assertive’ but unsubstantiated plots which conveniently demonstrate what the author wants us to see.

Some ‘uncertainty’ bands would make it far more convincing.

MichaelG.

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P.S. __ What’s the source of that graph ?

Edited By Michael Gilligan on 01/12/2021 17:56:52

[Andy StopfordParticipant @andystopford50521]

There have been a lot of comments re. the recent storm, power cuts etc. to the effect of "And now they want us to switch to electric heating. No thanks, I'll stick with gas"

So if there's a power cut, they'll still be able to run the gas boiler. Best of luck with that.

edit: In the 1970s few/no serious climate scientists believed in the "new ice age" scenario, this seems to have been mostly in the imagination of (non-scientifically trained) journalists.

Edited By Andy Stopford on 01/12/2021 20:13:50

[Michael GilliganParticipant @michaelgilligan61133]

This is a little more explanatory :

Ref: __ **LINK**

https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide

MichaelG.

[Grindstone CowboyParticipant @grindstonecowboy]

I expect the scientists know better than me, but if I was asked to measure carbon dioxide, I wouldn't choose to do it on the side of an active volcano…

Rob

[Ex contributorParticipant @mgnbuk]

I would have expected a bigger "hump" in the CO2 graph between 1938ish and 1945 – huge industrial production from largely coal based manufacturing + very high fuel & explosives usage + huge amounts of destruction.

Talking to the crew of the Canadian Lancaster fund raising to cover their fuel cost some years ago at Oshkosh, they used 50 US gallons of high octane fuel per engine per hour travelling unloaded – we sent 1000 bomber raids of heavily loaded Lancasters, Halifaxes etc. regularly. And a period documentary about a US B29 raid on Japan I watched recently quoted 7000 US gallons per aircraft for the round trip & there were over 500 B29s on the raid + a substantial Mustang escort force & these raids were also conducted regularly.

Such levels of fuel consumption alone over a 6 year period worldwide + ground force & naval usage would surely have caused an emissions "blip", yet the graph shows a dip just after 1930 & not much of a climb immediately thereafter ?

Nigel B.

[Nigel Graham 2Participant @nigelgraham2]

Interesting point, why an apparently small effect from WW2.

The 1930s saw a very large Depression which might account for the slight drop in CO2 levels, and there is a vague hump that might be from the War. It's possible the measurements of the time were not themselves not sufficiently accurate and international for large but short-term, temporary changes to be very apparent. If any were taken, of course.

To some extent too, wartime use of fuel for non-important purposes would have dropped drastically, possibly off-setting some of the military uses and effects. WW2 was also followed in many countries by the "Austerity Years", again reducing fuel use.

It looks almost as if economic depressions had more effect than the wars and destruction.

What is particularly significant though is the overall rise, and its steepening in the 1960s, combined with the traces merging to show human activity having become the primary source of atmospheric CO2 overall since WW2.

==

Ice-cores are a major source of palaeoclimate evidence. Another important one is cave deposits, by analysing sediments left by streams, and layers in calcite (stalagmite). Because caves take hundred of thousands of years to form, with some being possibly a few million years old, and their deeper conditions are fairly stable, they act as natural climate-evidence archives.

[SillyOldDufferModerator @sillyoldduffer]

Posted by mgnbuk on 02/12/2021 10:29:31:

I would have expected a bigger "hump" in the CO2 graph between 1938ish and 1945 – huge industrial production from largely coal based manufacturing + very high fuel & explosives usage + huge amounts of destruction.

Talking to the crew of the Canadian Lancaster fund raising to cover their fuel cost some years ago at Oshkosh, they used 50 US gallons of high octane fuel per engine per hour travelling unloaded – we sent 1000 bomber raids of heavily loaded Lancasters, Halifaxes etc. regularly.

…

Such levels of fuel consumption alone over a 6 year period worldwide + ground force & naval usage would surely have caused an emissions "blip", yet the graph shows a dip just after 1930 & not much of a climb immediately thereafter ?

Nigel B.

Not necessarily – most countries involved in WW2 saw massive dips in civilian consumption as their economies were directed into warfare rather than business as usual.

A 1000 bomber raid might sound like major fuel consumption, but they weren't all that common. Yes, lots of activity, but WW2 was small compared with the growth of commercial aviation. This source quotes an average in 2017 of 9,728 planes carrying 1,270,406 people being in the air all the time. And many of these are long-haul jets.

It may seem surprising, but the energy consumed by WW2 was relatively small compared with what's happened since. For example, in 1951 more than 80% of UK households didn't own a car. Today ownership averages about 1.4 cars per household – about 40,000,000 of them, averaging 10000 miles per year each.

Worldwide, about 1.5 billion cars are on the road. A little over 3 new cars are made every second.

Dave

[Ex contributorParticipant @mgnbuk]

WW2 was also followed in many countries by the "Austerity Years", again reducing fuel use.

But also a time of extensive rebuilding of damaged infrastructure & increased manufacturing effort (Export or Die ? ) plus the US & USSR expanding military production & excercising, so would the immediate post war period have seen much of a reduction ?

One graph that I did come across that seems to follow the trend of SoD's example suprisingly closely is this one :

So one may conclude that the increase in emissions appears to follow the increase in population quite directly ?

Other organisms in the natural world that expand at a rate that their environment cannot sustain tend to see rather dramatic reductions in their numbers – I doubt very much that science can do much to prevent a similar correction taking place for the human organsm at some point, even if the various "powers that be" could actually agree on a sustained course of action to try to alleviate any climatic effects.

And I equally doubt that my stopping my workshop activities would have much effect either (to try to get back to the original question ).

Nigel B.

[John AbsonParticipant @johnabson65530]

This article in Grist outlines the results of research into arguments denying climate change, in particular how denials are diminishing and criticism of solutions increasing.

Closer to home, has ME thought of using biodegradable mailing bags rather that polythene? My Chartered Quality Institute journal does, so it would appear to be perfectly possible .

[Mike PooleParticipant @mikepoole82104]

I doubt that the impact of all the Model Engineering or home workshop activity could be measured even if we all stopped partaking. It is also unlikely that we would do nothing if we gave up engineering. Many of the tools are quite likely to serve multiple generations. As devastating as the Coronavirus has been especially on a personal level for those affected it has made a tiny dent in the world population. This has probably already been compensated for by people in lockdown engaging in their favourite pastime and I am not thinking model engineering. I suspect that the Earth will survive with quite a diverse flora and fauna even if man does not. Man has had a wonderful gift of a beautiful planet so lets hope we can succeed in living in harmony with all the inhabitants, so far it has not gone well.

Mike

[Clock polisherParticipant @clockpolisher]

Good evening,

As I sit in my small workshop, in a house that uses about 24 MW of gas and 3 MW of electricity each year I feel very guilty about my working career.

I spent 35 years as a combustion engineer at a steel production facility where that amount of energy wouldn't keep the pilot light of a boiler running. The place as a whole could use more than 50 GW a week.

This brings me on to a subject that seems to be sadly lacking from any government plans for the energy future of Britain.

Steel undergoes a multitude of processes to turn either iron ore or scrap metal into the material we all take for granted. Many of those processes use gas. Whilst it is theoretically possible to do some of these with electricity, in practice it's impossible, the infrastructure would cost a king's ransom.

They could however use hydrogen.

All that I see happening is the government will use this to tax heavy industry out of existence in this country, which will push steel production further around the globe into other countries with less stringent pollution rules.

What then?

regards,

David

[duncan webster 1Participant @duncanwebster1]

I got rid of my last car when it had done somewhere north of 150,000 miles. This because of the government subsidised scrappage scheme. It went off to the crusher, and substantial amounts of energy were no-doubt used to shred it, re-melt, re-roll etc into new material from which to make a new car. There was actually very little wrong with it (needed new alternator bushes), I reckon that a lot less energy would have re-conditioned the engine (top end overhaul minimum), re-bushed all the suspension, and a reprogrammed engine management system would have got another 10 years out of it.

The mantra is Reduce, Re-use, Re-cycle, but we only seem to want to do the third. Similarly wine bottles, they re-use milk bottles so why not wine? If there was a substantial tax on non standard shaped bottles they would soon be all the same. As it is they are broken up and re-melted. Wine imports from Aus to UK comes in bulk and is bottled here, so it is within our control

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