"Net Zero"

[JohnW2]

I've never had the time/inclination to actually look into this, but I've often wondered how, say, the UK thinks that it might, one day, achieve "net zero" ('carbon emissions').

So long as human beings exist, and even if all domestic/industrial etc. carbon emissions could be eliminated (obviously impossible), there will always be at least some 'carbon emissions', since (an increasing number of) live human beings constantly breathe out CO2 (not to mention even more other animal life doing the same).

What, I therefore wonder, is it intended will be on the other side of the equation, 'to cancel' those inevitable emissions and thereby reduce the 'net' to zero - is it just a matter of 'planting trees' (and locking up carbon in concrete etc!), or are there other things?

Kind Regards, John

 

[ericmark]

I would think net zero means the carbon dioxide absorbed by plants equals the carbon dioxide released by animals or fires.

However country by country near impossible to measure, air circulates around the world, and plants give out carbon dioxide in the dark.

I also can't work out how you can weigh a gas, they talk of tons of CO² but one would need to cool and/or compress to make it a liquid before you could weigh it.

The new fuels I am sure are making it worse not better, never seen the smoke like that in previous years, only this year since supply of Welsh steam coal has dried up.

 

[mikeey84]

I think the main route is CCS, Carbon Capture Storage. There are very significant trials going on to move to hydrogen as a replacement for natural gas, which will likely be "blue" hydrogen, produced from natural gas, where the carbon is captured and stored. Lots of industry are at this moment trialling gas burners that either use 100% hydrogen, or a blend of natural gas and hydrogen.

 

[winston1]

I also can't work out how you can weigh a gas,

Our physics teacher at school did just that. He weighed a balloon on a balance and then blew it up and weighed it again. It was heavier.
Was never convinced. Supposing he had inflated it with hydrogen.

 

[mikeey84]

also can't work out how you can weigh a gas, they talk of tons of CO² but one would need to cool and/or compress to make it a liquid before you could weigh it

You can work out the weight of a gas using the gas laws.

Each molecule of CO2 is a known weight, so if you know how much there is, such as PPM, you can work out the weight

 

[mikeey84]

Our physics teacher at school did just that. He weighed a balloon on a balance and then blew it up and weighed it again. It was heavier.
Was never convinced. Supposing he had inflated it with hydrogen.

If he had, you would have been able to work out that the hydrogen weighed less than the air it had displaced

 

[Munroast]

if gas had no weight it wouldn't sit on the planet, like anything else with mass, gravity attracts it.

What, I therefore wonder, is it intended will be on the other side of the equation, 'to cancel' those inevitable emissions and thereby reduce the 'net' to zero - is it just a matter of 'planting trees' (and locking up carbon in concrete etc!), or are there other things?

Production of concrete is one of the biggest creators of CO2 on the planet. concrete is created from limestone and limestone is extremely rich in carbon (limestone is the remains of shells from sea creatures) to make concrete the organic material is burnt out of the limestone releasing vast amounts of carbon, in fact more co2 is released from the organic material than the oil gas or coal to heat it up. It is a disastrous material that we can't do without


Isn't it incredible to think that mountain ranges such as the Alps (and most of yorkshire) are all made out of limestone, there must have been a hell of a lot of shelled sea creatures once!

 

[ericmark]

Our physics teacher at school did just that. He weighed a balloon on a balance and then blew it up and weighed it again. It was heavier.
Was never convinced. Supposing he had inflated it with hydrogen.

Oh I remember that, and it was pointed out using compressed gas so retried with a plastic bag, and this time same weight.

I looked up Charlie's Law seems it helps parents get the support they need by providing for better access to advice on ethics and their rights, independent second opinions, and legal aid to ensure families do not face having to pay for costly legal representation and are not forced to rely on funding from outside interest groups.

And I thought it was one of the gas laws!

Does Net Zero mean if I put a net over my flue for the winter and the constants weigh no more at end of winter then it is net zero, then I am sure my oil central heating is net zero, as gas can escape through the net!

 

[JohnW2]

I would think net zero means the carbon dioxide absorbed by plants equals the carbon dioxide released by animals or fires.

Other than for the 'fires', you are talking about the biological carbon cycle, but the big picture is much wider that. In fact, what you say is incomplete even in relation to the biological cycle. For a start, it's not just CO2 - live animals also release other carbon-containing gases (e.g. methane), as can dead plants and animals when they decay (a process which released CO2 and/or methane etc., depending on conditions). Plants also release some CO2 into the atmosphere (but less than they absorb).

When I was at school, the 'natural' carbon cycle (i.e. excluding man-made components) was entirely biological, other than for naturally occurring fires and volcanoes etc.. However, I gather that it has been subsequently discovered/realised that geological and oceanographic components are a very significant part of the whole - CO2/carbonic acid falling on mountains etc.. can end up as new carboniferous rock, and oceans have the capacity to 'sequester' large about of CO2.

However, we aren't talking about those 'natural' processes, over which we have little/no control but, rather, about the real-world situation in which 'man-made' emissions are added to the biological ones.

Hence my question - in the quest for "net zero" what changes are on the side of the equation which increases atmospheric carbon-containing gases other than "planting trees". So far, @mikeey84 is the only person who has addressed that in this thread.

I also can't work out how you can weigh a gas,

As has been said, you could do so 'in a balloon' etc., but, in context, one doesn't need to. As has also been said, since we know the density of the gases of interest (CO2, methane etc.) we can calculate the weight of the emissions from the volume and concentration. If I knew the average amount of air you breathed out per minute and the average concentration of CO2 in it (both easy to measure), then it would be child's play to estimate the total weight of CO2 (hence 'carbon') you were putting into the atmosphere per year.

Furthermore, since we have a reasonable understanding of the chemistry which results in CO2 production in animals and plants (and a very good understanding of the chemistry which results in 'industrial emissions') it is very easy to ('theoretically') estimate the weight of CO2 (hence 'carbon') released into the atmosphere by those processes.

Kind Regards, John

 

[JohnW2]

I think the main route is CCS, Carbon Capture Storage.

That was obviously the sort of thing I was thinking of when I talked of "locking up carbon in concrete etc.", although I had not thought about what @Munroast has said about the large amount of emissions created by concrete production.

However, there are presumably countless other ways of achieving 'CCS' which are not, in themselves, major creators of emissions, but the scale of the atmospheric CO2 we are talking about (I would guess 'gigatons') is so 'astronomical' that I wonder how realistic it is to believe that we could appreciably impact on this by 'capture and storage' - apart from anything else, there could be a problem of 'storage space'!

However, as I've just written, I understand that 'nature' is doing a fair bit of this for us, by converting atmospheric CO2 (delivered by rain) intto 'rocks'.

Kind Regards, John

 

[ericmark]

(a process which released CO2 and/or methane etc., depending on conditions)

I thought methane was one of the paraffin series, CnH2n+2 and is a fuel rather than a waste product from burning?

 

[JohnW2]

I thought methane was one of the paraffin series, CnH2n+2 and is a fuel rather than a waste product from burning?

Well, yes, it's a hydrocarbon. It's not a "waste product of burning" but, as I said, is one of the potential products of decay of dead plants and animals.

It's a considerable over-simplification but, in general, when there is plenty of air/oxygen around ('aerobic' decay, as in frequently-turned compost heaps) decay of biological material will produce CO2, whereas if air/oxygen is absent/sparse ('anaerobic' decay, as in landfills) will produce CH4 (methane). One doesn't need a chemistry PhD to understand why - converting organic materials into CO2 obviously requires the "O", but converting to CH4 doesn't

Although there are now often attempts to capture and make good use of it you surely must have seen pipes sticking out of landfill sites with the methane burning as a perpetual flame at the top?

I think methane is much worse as a 'greenhouse gas" than is CO2.

Kind Regards, John

 

[mikeey84]

apart from anything else, there could be a problem of 'storage space

The main idea, as I understand it, is to pump it I to empty gas fields, which is somewhat ironic IMO

that we could appreciably impact on this by 'capture and storage

CCS will only work when captured at source, and then, only when CO2 is produced in significant quantities, so power stations, and hydrogen production sites. Fitting CCS to a car or a domestic boiler is a non starter, as the concentration gradient isn't high enough.

The idea is that if we can capture carbon at source, and use it to produce non carbon producing fuel, such as electricity or hydrogen, we can decarbonise significantly, which along with tree planting and other more "natural" measures will lead to net zero

 

[ericmark]

The problem is the amount of miss information, the gas used to insulate green houses is argon gas, as with any other double glazed unit, but argon gas is not what we think of as a green house gas.

I don't think anyone would make that error, but we see so many silly statements we or at least I take them all with a pinch of salt.

The gases used for refrigeration was clearly bad, causing a hole in the ozone layer, but the Pterosaurs it seems likely could not fly today due to lack of CO² so clearly a change in the atmosphere will change the planet, taking back to how it was long ago, even in man's life time on the planet we know things have changed, the sphinx as signs of water erosion due to rain, and when I went to work in Algeria in Hassi'r mel it was found the smoke from the gas plant resulted in the land below becoming cooler, this in turn resulted in a little rain, so the land became greener due to the smoke.

The result of burning fossil fuels is in the main guess work, no harm in reducing the amount burnt, but one needs to look at easy methods first, far easier to electrify a railway than road transport, so rail should come first, the fact that not all the railways are electrified points to economic rather than planet saving being the reason for the CO² push.

When people have done the sums, we see results which don't seem to make sense, all the narrow gauge railways of Wales use less CO² to one plane to USA, I can see the reason for people to move around by plane, but air fright? Why have we not returned to using the mail train?

 

[mikeey84]

Why have we not returned to using the mail train

A lot of money is being invested in DIRFT and similar facilities, and one of the main factors in favour of HS2 is removing passengers from the WCML so that more freight can hauled.