Monday, March 31, 2008

Carbon & its history

You didn't realise how basic peoples understanding of a well known problem can be at times.

Yes, not all carbon was created equal. History counts!

Here is part of a thread on the subject.

My initial post, part of a wider thread.

> One issue is how much GH gases you release, but more important is where the carbon (including embody energy) came from in the first place. Is a fire better that an electric light? Would the depend of if the electricity is solar or gas or oil or coal fired. Is the fire a wood fire or brickettes?
> I always ask, "where was that energy a year ago, 10 years ago, a hundred years and a thousand years ago?" Ultimately you're going to end up in one of four places. The sun, heat in the crust or below, the moon (tidal) or in a since mined crust deposit (I use this wording to cover exhaustible fossil fuels & radioactives).
> I'll leave you to work out witch 3 are exceptable and witch one isn't!

The initial response.

Hi there I'm still a newbie with lots to learn. So correct me if I am wrong you are saying condensed burning a 10 year old tree is more acceptable than condensed burning a 10 million year old tree and of the same ammount ?

I think the question was is the release greater at the power station than if every household was burning ?. There is simply no space on standard household blocks to have a huge array to produce their own solar energy to meet the same loads, that would also be the argument that appliances not just lights are just as inefficient as current solar technology :)

My reply, on why I think carbon is not all equal. History (source) counts.

The carbon in the tree is carbon that is in the carbon cycle. It moves through different parts of the biosphere over time. Moving between plants, animals, the atmosphere, the oceans and soils. Each of these five can be though of as a 'pool'. This carbon is constantly on the move. Part of the ongoing cycle of the biosphere and life. This carbon has fuelled human societies since we could rub two sticks together and this movement is generally fuelled by the sun.

Fossil carbon has been out of the above pools for ten if not hundreds of millions of years. When you burn fossil fuel you’re releasing 'new' carbon on the biosphere, and it usually ends up in the atmospheric or oceanic pools.

So when you burn carbon to make light (or movement or heat etc), it’s the history of that carbon that is important.

When it comes to removing carbon, it don't matter which carbon you remove.

How we farm, graze, forest and fish is important, but to a lesser degree. These processes determine how carbon is distributed between the five 'pools'. We need to move carbon to the plants, animals and the soils 'pools' from the atmospheric and oceanic 'pools'. The atmosphere and the oceans are so closely coupled in some ways they are just one 'pool'.

When I use the term solar, I'm referring to all sun powered systems, photovoltaic, thermal (dish & rheostat systems), biomass, wind and waves. Remember waves are driven by the wind. Wind in turn is driven by differential heating of the earth by the sun. You’re right, photovoltaic are still so poor on a system lifetime basis, that they are still effectively at the research & prototype stage. We got to start somewhere. Edison is said to have tested 10,000 configurations to get an appreciable one.

The reply about my thoughts

Thanks knoll. I never saw it that way, but oil has been referred to as

ancient sun energy or something like that. I would see it worse off
though if everyone started mass polluting from their homes don't you
think ? Thats why incinerators were banned, wasn't it. If incinerators

were banned that is a double standard for the industries then heh :)

Sorry i send this offlist so I don't bore the list with my ranting so
people don't get the wrong idea of me as i'm new :\

My second reply. Here I try to tease carbon out of other pollution issues. This case local ones.

Yep, oil has been referred to as ancient sun energy (coal too), the operative word is ancient. What this means is that the carbon is not in one of the biospheric carbon ‘pools’, but is in the geologic carbon ‘pool’.

There is normally very little movement between the biospheric carbon ‘pools’ and the geologic carbon ‘pool’. Some oil tars seeps to the surface here, some dead vegetation and animals sink to the bottom of a swamp, lake or sea and is buried there. The last 250 years ain’t normal.

The bans on incinerators, leaf burning etc are spot bans to stop local pollution hot spots. As with any activity, there are likely to be GH effects. There are two ways to look at leaf burning. You’re just releasing back to the air, carbon that was taken out last spring & summer. The other was is that you’re diverting carbon. You’re releasing carbon back to the air via near instant combustion instead of via slow decay, absorption into plants etc. You’re changing the distribution between the ‘pools’, at least in the short term.

I posted the comment, hoping they help people understand the cycle of life (particularly carbon) better.


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