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Cement is 3 times more polluting than aviation fuel


NSS

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6 hours ago, NSS said:

According to this article - https://www.bbc.co.uk/news/science-environment-46455844

 

I guess it's a good job aircraft are not made of concrete then!

 

 

the thing is we do not have to fly .

 

when world government has the balls to tax aviation fuel --then usage of it will change ---same goes for heavy oil used in ships .

 

 

we do have to build things 

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16 minutes ago, scottishjohn said:

the thing is we do not have to fly .

 

when world government has the balls to tax aviation fuel --then usage of it will change ---same goes for heavy oil used in ships .

 

 

we do have to build things 

Sure, but ICF, passive slabs.... ?

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any thing that cuts down total energy usage must be good .

I read somewhere that the amount of energy used to make a PV panel is more than it will give back inits full life -

there are no free lunches  .

maybe when we get orbital production -when we can take energy direct fron sun outside our atmosphere  and manufacture in a vacumn and zero gravity-then things will change maybe

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At least the green lobby are turning away from entirely blaming transport fuel.

 

What are they going to do about agriculture, can't have all those flatulent cows in the countryside can we?  The "industrial revolution" is widely blamed for mmgw, but I don't see a countryside full of cows as an industrial revolution problem.  Rather that other problem that nobody will talk about, that is the unsustainable and still increasing human population figures.

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David Attenborough is of the opinion that over population is the greatest threat to this planet. Going back to cement/concrete I have heard the argument that because it can last so long (Romans’ invented it and some of their stuff is still standing). The pollution is relevant to its lifetime so as long as we use it to build stuff that is allowed to remain usable for decades it’s not so bad. I suppose that if a concrete structure is demolished if it is crushed and used as hardcore is saves digging out stone, so still being used?

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1 hour ago, scottishjohn said:

I read somewhere that the amount of energy used to make a PV panel is more than it will give back inits full life - 

 

Then you've read some bullshit. Peer reviewed articles show that, at least from the CO₂ perspective, PV panels “pay back” (in the sense of displacing emissions) in a small number of years depending on the way they're manufactured and where they're used. For some cases it can be as little as about a year, in others a few years.

 

To be honest, I'm getting almost as sick of the anti-renewable bullshit as the AGW-denying bullshit. And the idiots who repeat it uncritically when some simple arithmetic should tell them it's wrong. 200 W panel, 800 hours a year generation for 20 years gives 3'200 kWh. Even at 5p/kWh that'd be £160. That's most of the cost of the panel which isn't primarily energy costs to start with (who knows the break down but mostly it'll be the capital cost of the manufacturing plant).

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1 hour ago, Ed Davies said:

 

Then you've read some bullshit. Peer reviewed articles show that, at least from the CO₂ perspective, PV panels “pay back” (in the sense of displacing emissions) in a small number of years depending on the way they're manufactured and where they're used. For some cases it can be as little as about a year, in others a few years.

 

To be honest, I'm getting almost as sick of the anti-renewable bullshit as the AGW-denying bullshit. And the idiots who repeat it uncritically when some simple arithmetic should tell them it's wrong. 200 W panel, 800 hours a year generation for 20 years gives 3'200 kWh. Even at 5p/kWh that'd be £160. That's most of the cost of the panel which isn't primarily energy costs to start with (who knows the break down but mostly it'll be the capital cost of the manufacturing plant).

 

Good post and analysis.

Similarly, wind turbines can repay themselves in under a year- depending on site conditions etc.

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are you a politican 

"Then you've read some bullshit. Peer reviewed articles show that, at least from the CO₂ perspective, PV panels “pay back” (in the sense of displacing emissions) in a small number of years depending on the way they're manufactured and where they're used. For some cases it can be as little as about a year, in others a few years."

that statemnt is so open ended  it does nothing to  convince me that as I stated --(nothing to with emissions --never mentioned co2) --that the energy required to make them -- in KW 

I do not know the exact costs ,as power in china will be alot cheaper than here as its coal fired - thats why they not made here .

without definatvie data  you cannot  say its bullshit ,well no more than the other side of the argument--where production rates and life span is all guessing --pv has not been going 20 years yet

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I seem to have awakened the green energy trolls .

again we will see in20years how many of those turbines are still working and repaired ,once the FITS are no more .

turbine pay back in a year !!!!.  if it did it would be worn out in 2 years 

lots of them in scotland,on farms etc  no longer working due to cost to repair them .

none of them will last as long as a good hydro set-up 

the ones round here were built in 1937--still going --80years +

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@scottishjohn, the Peer Review process is a commonly accepted corner stone of all informed, objective discussion throughout the world.

It provides an opportunity for  informal feedback among peers. Peer Review actively hinders vested interest  (because reviewers don't know who else is on the review team) . It isn't perfect. But it's the best that exists.

 

So, about that list, then. Got one?

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One of our chosen lines of keeping threads informative is to only reference information wherever practicable. Linking to such information is of further benefit to the post / thread. 

Stating ones own opinion as if it were fact, requires said facts to back it up.  

Lets please keep it factual, AND informative please :)  

Mods. 

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3 hours ago, joe90 said:

Going back to cement/concrete I have heard the argument that because it can last so long (Romans’ invented it and some of their stuff is still standing).

 

I believe part of the problem is many concrete structures will likely not last anywhere near as long, mainly due to corrosion of the steel reinforcement - which the romans didn't use.

See https://theconversation.com/the-problem-with-reinforced-concrete-56078

 

Thinking about our own build (rather than bridges, skyscrapers, etc) our SE says if kept dry and protected, any reinforced concrete should last 'a long time' so it shouldn't be an issue. However, given we're aspiring to a design life of more than 150 years I'm keen to explore options to reduce the risk, given re-inforced concrete will form crucial parts of the structure. Replacement of any steel rebar with stainless steel looks like a realistic alternative, with really a fairly small cost considering it might (?) double the life of the structural element, though TBH I've not investigated yet. Basalt another option.

 

Roman concrete also superior to modern due to their use of volcanic ash 

https://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/15190/The-Secret-Ingredient-in-Ancient-Roman-Concrete-is-Seawater.aspx

 

Concrete block is another matter and there's a variety of possibly more sustainable options such as types made by http://www.lignacite.co.uk/ but I've not looked into that fully either.

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2 minutes ago, kxi said:

 

I believe part of the problem is many concrete structures will likely not last anywhere near as long, mainly due to corrosion of the steel reinforcement - which the romans didn't use.

See https://theconversation.com/the-problem-with-reinforced-concrete-56078

 

Thinking about our own build (rather than bridges, skyscrapers, etc) our SE says if kept dry and protected, any reinforced concrete should last 'a long time' so it shouldn't be an issue. However, given we're aspiring to a design life of more than 150 years I'm keen to explore options to reduce the risk, given re-inforced concrete will form crucial parts of the structure. Replacement of any steel rebar with stainless steel looks like a realistic alternative, with really a fairly small cost considering it might (?) double the life of the structural element, though TBH I've not investigated yet. Basalt another option.

 

Roman concrete also superior to modern due to their use of volcanic ash 

https://www.engineering.com/DesignerEdge/DesignerEdgeArticles/ArticleID/15190/The-Secret-Ingredient-in-Ancient-Roman-Concrete-is-Seawater.aspx

 

Concrete block is another matter and there's a variety of possibly more sustainable options such as types made by http://www.lignacite.co.uk/ but I've not looked into that fully either.

re bar made from grp  is available --just expensive 

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1 hour ago, recoveringacademic said:

@scottishjohn, the Peer Review process is a commonly accepted corner stone of all informed, objective discussion throughout the world.

It provides an opportunity for  informal feedback among peers. Peer Review actively hinders vested interest  (because reviewers don't know who else is on the review team) . It isn't perfect. But it's the best that exists.

 

So, about that list, then. Got one?

that should be aimed at the man stating he has read peer reviews ,he should have posted links . then the scope of the review could be judged 

 

 

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