carbon or carbon dioxide ??

[matt_xyz]

yes, and also because CO has a short atmospheric life so only causes local problems. I agree it is theoretically a greenhouse gas.

CH4 has 60x the global warming potential of CO2, per unit, according to some estimates.

I've never heard carbon neutrality interpreted as implying zero emissions, but rather that any emissions are offset. Hence carbon neutral albums by Coldplay , carbon neutral construction projects, flights etc. All great until somebody cuts the trees down....

Matt

[eeyore]

quite so - or half of them die because they were planted way to close and then not given any aftercare.

On the other point take a look at govt proposals (or rather journo reporting of govt proposals) for things like wind farms and nuclear powerstations - these are littered with refferences to carbon neutral generation etc. I agree with you that co2 is the largest thing in the public eye but lazy reporting leaves journos using carbon and cor interchangably. ( and dont even lets get started on their conflation of global warming, GHE, and climate change )

edit : presumbably CO has a short atmospheric life because it "wants" another oxygen ion - thus out putting CO will contribute to GHE because when the CO will eventually become Co2

[eeyore]

Originally Posted by pressld2

You need to burn them to free the atoms from the molecules that they are currently in. A lump of coal is pretty inert and does not give off CO2 on it's own.

I takes ridiculously high temperatures to burn a diamond but yes, it too would produce CO2 if you did.

Dave P.

another really big outputter of Co2 is the manufacture of cement - the underlying issue being that you have to cause carbon to react with oxygen - or cause a carbon containing molecule to react with oxygen (in this case calcium carbonate (CaCo3) - being reduced to calcium oxide then calcium hydroxide. You dont necessarily have to "burn" anything for this to happen.

[pressld2]

Originally Posted by eeyore

You dont necessarily have to "burn" anything for this to happen.

That's true Pete, although my original comment was specifically in relation to carbon based fuels.

Plus I remember a chemistry teacher (many, many years ago) who delighted in describing all oxidising reactions as "burning". Even the rust on his car: "The steel is burning but very, very slowly"!

Dave P.

[Paul mabbott]

Originally Posted by eeyore

another really big outputter of Co2 is the manufacture of cement - the underlying issue being that you have to cause carbon to react with oxygen - or cause a carbon containing molecule to react with oxygen (in this case calcium carbonate (CaCo3) - being reduced to calcium oxide then calcium hydroxide. You dont necessarily have to "burn" anything for this to happen.

I think so ... the process involves releasing the carbon dioxide (of the eponymous carbonate) and it uses heat, thus producing more carbon dioxide.

[Paul mabbott]

Originally Posted by eeyore

I agree about creating sinks for Co2 (I also agree that most of these schemes are little more than a con) - however a lot of people use carbon neutral to mean that a product or activity doesnt generate any Co2 - and i was just pointing out that in this context it would only be accurate if you didnt generate other greenhouse gasses either.

We've debated the meaning of 'carbon neutral' before. I don't think it can be used to describe things like offsetting car/plane travel using fossil fuels - people might think that they're being 'carbon neutral' but they're not, they're attempting (usually not very well) to compensate for their fuel use.

What is carbon neutral, in my reckoning, is to coppice trees and use the wood for fuel - chopping the wood removes a carbon sink and burning it releases carbon dioxide but as the coppice regrows it uses up the equivalent amount of carbon dioxide that was released so over an annual cycle the process is carbon neutral.

Yes, methane is as significant a greenhouse pollutant as carbon dioxide - produces in the intestines of ruminant animals in particular. Again, it's one of those things that humans can reduce massively by eating far less meat. There is no way that intensive cow farming can be carbon neutral.

[eeyore]

Originally Posted by Paul mabbott

What is carbon neutral, in my reckoning, is to coppice trees and use the wood for fuel - chopping the wood removes a carbon sink and burning it releases carbon dioxide but as the coppice regrows it uses up the equivalent amount of carbon dioxide that was released so over an annual cycle the process is carbon neutral.

.

you have a good point - in fact a coppiced tree absorbs slightly more co2 than that released by burning the coppice product because each stool will grow slightly larger with more biomass.

however even this would only be truly carbon neutral if the wood was cut by hand and conveyed to the fireside by carbon neutral means - if (as is common) it is cut with petrol fueled chainsaws, then hauled out using quads and tractors, logged up with chainsaws , then conveyed to the customer in trucks or vans then it still has a carbon footprint - which illustrates that it is virtually impossible to achive true carbon neutrality in the modern world.

[Ipso Facto]

Originally Posted by eeyore

... it is virtually impossible to achive true carbon neutrality in the modern world.

I think that we are losing the plot a little here. Yes, the phase 'carbon neutral' is an ideal but this isn't about counting the number of decimal places.

Carbon neutrality is about communities or individuals striving to reduce their carbon footprints to an absolute minimum and as a totum I think that 'carbon neutral' focuses the mind better than the phrase 'nearly carbon neutral'. In other words, whilst a 100% saving may be unattainable in practise, an 80% saving in the net carbon released is still better than 0% and 81% is better than 80! None of us know what our individual limits are until we try so why lower the bar before we have?

Personally I managed to reduce my own carbon footprint by 47% last year and whilst the next savings are going to be more difficult it doesn't mean that I have stopped trying.

[eeyore]

Originally Posted by Ipso Facto

I think that we are losing the plot a little here. Yes, the phase 'carbon neutral' is an ideal but this isn't about counting the number of decimal places.

Carbon neutrality is about communities or individuals striving to reduce their carbon footprints to an absolute minimum and as a totum I think that 'carbon neutral' focuses the mind better than the phrase 'nearly carbon neutral'. In other words, whilst a 100% saving may be unattainable in practise, an 80% saving in the net carbon released is still better than 0% and 81% is better than 80! None of us know what our individual limits are until we try so why lower the bar before we have?

Personally I managed to reduce my own carbon footprint by 47% last year and whilst the next savings are going to be more difficult it doesn't mean that I have stopped trying.

i understand that and for individuals i agree - however for those advertising comercial services or products it is unethical (and possibly contrary to the sales of goods act) to describe your activity as "carbon neutral" if it isnt 100%

[Ipso Facto]

Originally Posted by eeyore

i understand that and for individuals i agree - however for those advertising comercial services or products it is unethical (and possibly contrary to the sales of goods act) to describe your activity as "carbon neutral" if it isnt 100%

I understand where you are coming from but let the market develop and then clamp down on the offenders I say. I think publicity is probably the most important criterion at the moment: let's wait to criticise the gross 'untruths' when a few more suppliers have been attracted into the market place and the public is a bit more switched on. I the short term, let the educated users judge the claims for themselves. I would assume that there will be some sort of 'carbon efficiency' mark coming out at some point.

I seem to remember something similar happening when organic food first made a splash on the market.