Thursday, December 10, 2009

Getting rid of carbon 1

This post is a follow up to Climate change and policies that work.

One thing that I had hoped that might come from the immediate defeat of the Government's emmission trading legislation was a more detailed discussion on options. There is now, I think, a real risk that this will not happen. The debate is too locked in to current ways of thinking.

This post and any follow-ups are an attempt to get people people thinking.

Statement of the Problem

Let's start by setting a context.

Say Australia's current emmissions of CO2 are 100, We want to reduce this to 70 over the next twenty years. During that time, economic growth means that, on current approaches, CO2 will increase to 140. So we actually need to reduce CO2 from 140 to 70, down 70 not 30.

The numbers have no meaning, of course. They are just there for illustration, to set a frame. Serious CO2 reduction is not a small thing.

I will deal with issues in current approaches later. In the meantime, I just want to outline a series of possible measures.

I have not attached numbers because I don't know them, nor can I guarantee that my suggested responses make sense. They are just based on things I have picked up in passing.

One of my personal drivers in writing this post is that I am not sure that CO2 reduction can be properly achieved just by current mechanistic approaches.My feeling is that we are going to have to do a whole lot of things.

The suggestions that follow are in no particular order.

Home Grown Electricity

As a case study, on Ochre Archives, Phillip Diprose has just installed a combination of solar and wind generation. You will find the story in order here, here, here, here and here.

In a way, Philip is a special case. The grid is some distance away. Yet we have already seen this type of approach in a domestic context.

Two sets of problems need to be addressed.

One is the front end cost. These systems can be expensive, and will become more so as any ETS drives up input costs. Further, green house gasses are themselved embedded in the equipment used.

The second is ensuring connection with the grid, so that surplus power goes into the grid. The technical issues appear to have been resolved. The remaining issue is ensuring that price paid for electricity gives a reasonable return for domestic and commercial building owners.

If every home, office or commercial building generated its own power, then we could use the newly created surplus power flowing from existing systems in industry, including higher polluting industries, thus giving us the industrial outputs we need including aluminium and steel without extra imposed cost, or at least at a reduced cost, because the emissions have been balanced.

Note, and as I commented in my last post, that the impact of current policies in this area appears to have disadvantaged green power generators.

Home Gardens

I accept that this one is a hobby horse of mine because of the way that NSW Government water restrictions stopped me gardening in a water effective way while allowing other people to top up swimming pools. As a result, we ended up using vegetables bought in from other places, importing water while adding to green house gasses through transport.

Not a big one, perhaps. However, encouragement of home gardens is likely to have not just a positive green house effect but other social benefits as well.

By the way, the emphasis on water saving on the Australian Department of Climate Change web site is very modern urban and really has very little to do with climate change as such.

Retrofitting Existing Buildings

This appears to be quite a big one if the discussion I have heard have any validity. However, there is an enormous range from the home to the commercial and industrial. Further, the imbedded greenhouse costs in materials and equipments used have to be factored in.

Still, I have heard estimates quoted, I cannot quote the source because of the elapse of time, that suggest very large gains.

Wood, Wood Fires and Forests

This is quite a complicated area from my perspective. Let's start by outlining my understanding so that it can be corrected if I am wrong.

Take an area of land and plant trees. The trees capture carbon. As they grow, they drop leaves and branches. As this decomposes, some goes to into the atmosphere as green house gases, some into the soil as soil carbon.

Upon full maturity the carbon gains are the carbon in the tree minus any carbon being saved under the previous land use system minus any carbon emitted from decomposed leaves and branches. When the trees die, they resend the carbon into the atmosphere.

Cut down say the Amazon rainforests and then burn the trees to clear the ground and the whole lot goes into the atmosphere.

Preserve an old growth forest and you come to something approaching a carbon neutral position in which carbon from tree decay is offset by carbon absorbed by tree growth.

You can leverage the gains from trees. Use dead trees in heating and you get the heat for the same green houses gases that come from natural decay. Cut down a tree and use it in heating but plant another one, you may bring green house gases foward a little, but the effect is longer term neutral. Turn the trees into wood for furniture or building materials, and you may extend the point at which carbon goes into the atmosphere.

So trees are good, but you have to take into account any carbon savings lost from previous use. You also have to take into account conflicts over land-use. There is a very strong view in the bush that current and prospective approaches are leading to inappropriate forestation.

I will look at these issues in my next post.



wood building materials said...

Always got to get rid of carbon there is alot of alternatives

Anonymous said...

offsets are a scam!