Direct Air Capture Carbon Sequestration Technologies

Hi Mark another thought that might make its way into the building code initiatives:

This is in response to an email about Mitsubishi’s new modular carbon capture technology. 

Hi Jan, I am skeptical. Not because of the chemistry – there are dozens of chemistries for sequestering CO2, for instance NASA used lithium hydroxide on the Apollo moon rockets – but because of the cost. Current estimates are about $100-$200 per ton captured. You can buy a carbon offset in the regulated market for about $50 a ton and about $15 a ton in the unregulated markets. They have the same effect.

Unlike solar panels and wind farms where there is no consumable cost, all these carbon capture technologies use a consumable (Lithium hydroxide in NASA’s case, some source of amines in this Mitsubishi example) which means there is a cost you cannot get below for chemical-based carbon capture. Hence economies of scale, that have been so successful in solar and wind, cannot reduce the marginal cost to zero. The cost of the consumable chemicals sets a floor on the cost per ton of the carbon capture. 

The cheapest way to sequester carbon is to cut down a mature tree, plant a new one to replace it, saw the tree into planks and use them to build a house. This sequesters the carbon for about 100 years. There is no incremental cost as we do this already and people are perfectly happy paying $4 for a 2×4. What it needs is a building mandate to use wood rather than steel and concrete. Wood can be made into glued/laminated beams that can build up to 4 stories high.