Carbon Capture and Storage

So I ran a poll on Instagram and 2/3 of people said we should invest in this. Not surprising as it does feature in pretty much every climate strategy and model we have. A few raised the issue of trees, absolutely we should have more trees! Trees and CCS are not opposites though, we need both. Even the 1 Trillion Tree Foundation say we need CCS. Trees can (counter intuitively) release more carbon than they absorb and cannot just be planted everywhere at will. We do of course need to reduce emissions but this post is taking that as a given.

CCS is very viable in some situations.

However, CCS comes in many forms and is misunderstood and unfairly maligned.

Bioenergy CCS

This is when you grow an energy crop (like elephant grass) which absorbs carbon dioxide as it grows (photosynthesis). You then burn it for electricity and capture the carbon from the smoke with carbon dioxide scrubbers which essentially “grab” CO2 molecules from the smoke.

Direct or Air Capture

When you suck CO2 through a fan and scrubbers again grab the molecules out of the sky.

These are the two types you see in the news. Bioenergy is a bit “icky” sometimes due to land use, fertiliser, pesticides etc. Direct is equally dubious as CO2, although very high for human life, is relatively low in the atmosphere at 410 parts per million of air. It’s not the most efficient use of a scrubber. They work really well in smoke stacks and chimneys because the CO2 level is high and the efficiency is higher.

Sort of like how you could hoover more sand from the beach than in the air. If you wanted to hoover sand (I don’t know why), you would go to the beach. You want CO2, you go to the chimney.

So it doesn’t work then?

It can, there is a more common method but it is not new, the first commercial carbon capture plant was in 1974 and the earliest mentions of it are the 1920’s. It was made by an oil company. This is where climate some activists start getting a bit upset. If you capture CO2 from a chimney with a scrubber the CO2 is absorbed in a liquid, this liquid can then pumped underground which forces oil up. It’s a more efficient way of getting oil out and it does work. If you take this away then oil exploration would be more polluting than it is.  

The principal works and is being expanded widely with a slight tweak. Instead of using it to force oil up, we just store it underground. We can capture it from any polluting building, there is a transport cost to putting it back in the ground but it is significantly less than not capturing it so the raw carbon economics do work. The technology does work. For all that oil and gas has done, their ability to invent and implement infrastructure is impressive. They are still heavily involved but now are alongside huge corporations like Microsoft and Google who are putting billions into this. Technology moves quickly and money and competition make it move even faster.

Carbon tax and CCS together is a game changer. It turns CCS into a far more viable prospect. If you pay for every tonne you emit, and get credit/reduction for sequestration then emitting becomes more expensive. The cost of “reducing emissions” becomes lower relative to the cost of continuing at a higher tax rate.

CCS also has spillover effects when mixed with tax. Electric cars become far more viable, same with trains etc.

CCS is absolutely possible, viable and necessary. Not on its own, climate change is a 1000 problems rolled into 1 and we need 1000 solutions. It’s not trees or CCS, it’s both.

Success! You're on the list.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: