Direct Air Capture or Fuel from Thin Air

Direct Air Capture (DAC) may become an important weapon in the battle to mitigate CO2 emissions. In this technology machines and chemical processes are used to remove CO2 directly from the atmosphere. In basic terms the air is blown through a radiator type grid where, aided by catalysts, the process of CO2 capture and extraction takes place. I saw recently work being done to extrace CO2 form the sea. The argument for this is that the sea has a higher concetraton of the gas and can absorb before saturation.

The UN Inter Governmental Committee states that 13Bn Tonnes of CO2 will need to be removed from the atmosphere by 2050 to keep the rise in planets temperature under control.

Iceland is operating a plant to take 4,000 tonnes of CO2 out of their atmosphere,powered by geothermal energy.

Costs are still being assessed and can be as high as $580 per tonne. So, it is important, if this technology is to play a significant role that the cost of the energy needed is low.

My dream is that in hot, sunny countries, the rich world could build DAC plants for the locals to operate. This idea could follow the building of desalination plants where there is a desert is close to an ocean and irrigate currently barren earth.

There are many industrial uses of CO2 in industry, so in addition to a plant using this gas, the addtional siting DAC installation near a factory creating CO2 could be both an environmental and economic win.

Fuel Synthesis

This is another process, sucking in air providing it with chemical catalyst and energy and the CO2 content reverts to fuel for a car. Air Fuel Synthesis is modern-day alchemy?

In an isolated community with a windmill or solar panel that does not use all the energy produced, the surplus can drive the air synthesis for an hour or two before reverting to the normal load. The owners can then go and pick up the fuel just as they might with their hen’s eggs.

Of course, the cost of the fuel is inflated over that of the market, so unless the energy used has little economic value, which is usually unlikely, or it cannot be used at that period of time (termed Stranded Energy). Or the cost of fuel at that market location is high, such as on an island, an isolated hillside farm.

If the community is very remote, then the cost of shipping the fuel will be inflated. The extreme situation of that was in military bases in Afghanistan, where drinking water and petrol both cost $100 per gallon!