Whether you believe climate change is a natural occurrence or completely man-made, you have to admit that it’s a real problem the globe is facing today. The sea levels are rising, wildfires are breaking out, and the globe’s overall temperature is almost continuously “unseasonable.” So how can we begin to solve this problem?
BBC Science Journalist Gaia Vince highlights the importance of offsetting carbon dioxide emissions by planting more trees, but what happens when there just isn’t enough space on the planet to plant the trees for the problems we have today? When the natural way isn’t an option, then efficient artificial trees may be the solution.
Vince points out the work of Klaus Lackner, the director of the Lenfest Center for Sustainable Energy at Columbia University, who has developed an artificial tree that can absorb carbon dioxide emissions 1,000 times more efficiently than real trees. The bonus for such a development is that Lackner’s “trees” do not require sunlight to work. Vince explains:
The leaves look like sheets of papery plastic and are coated in a resin that contains sodium carbonate, which pulls carbon dioxide out of the air and stores it as a bicarbonate (baking soda) on the leaf. To remove the carbon dioxide, the leaves are rinsed in water vapour and can dry naturally in the wind, soaking up more carbon dioxide.
Lackner calculates that his tree can remove one tonne of carbon dioxide a day. Ten million of these trees could remove 3.6 billion tonnes of carbon dioxide a year – equivalent to about 10% of our global annual carbon dioxide emissions. ‘Our total emissions could be removed with 100 million trees,’ he says, ‘whereas we would need 1,000 times that in real trees to have the same effect.’
Lackner’s “trees” are a potentially ingenious solution, but what should happen to the stored carbon dioxide byproduct the “trees” absorb? Vince suggests that the carbon dioxide be converted into liquid fuels to power cars, generators, airplanes, and ships. A process can turn carbon dioxide, when reacted with water, into carbon monoxide and hydrogen. Then it could be converted into hydrocarbon fuels like methanol or diesel.
This seems to be a great solution to the Earth’s climate change problems, but what gets in the way of this plan is, first, admitting there is a problem, and secondly, actually footing the bill to pay for Lackner’s “trees.” Vice suggests oil companies can take on this burden:
We have the technology to suck carbon dioxide out of the air – and keep it out – but whether it is economically viable is a different question. Lackner says his trees would do the job for around $200 per tonne of removed carbon dioxide, dropping to $30 a tonne as the project is scaled up. At that price – which has been criticised as wildly optimistic (the American Physical Society’s most optimistic calculations for direct air capture are $600 per tonne of carbon dioxide removed, although the UK’s Met Office is more favourable) – it starts to make economic sense for oil companies who would pay in the region of $100 per tonne to use the gas in enhanced oil recovery.
The problems we face today will be the problems we face tomorrow, so understanding that climate change is something that needs to be managed and something that will never go away is important. Maybe looking for an artificial solution is the best way to supplement the natural ones.