By Paul Homewood
Matt McGrath is finding out there is no such thing as a free lunch!!
Technologies that can remove carbon dioxide from the air could have huge implications for future food prices, according to new research.
Scientists say that machines that remove CO2 from the air will be needed to keep the rise in global temperatures in check.
But these devices will have major impacts on energy, water and land use.
By 2050, according to this new report, food crop prices could rise more than five-fold in some parts of the world.
In the wake of the Paris climate agreement signed in 2015, researchers have tried to understand what keeping the world under a 1.5C temperature threshold would mean in practice.
The Intergovernmental Panel on Climate Change (IPCC) reported on this question in 2018, and found that keeping below this temperature rise would require the world to reach net zero emissions by 2050 but would also need the removal and storage of large amounts of carbon dioxide from the atmosphere.
One of the ideas on how to achieve this is called BECCS – bioenergy with carbon capture and storage. It means growing crops that soak up CO2, then burning them for electricity while capturing and burying the carbon that’s produced.
Image copyright Getty Images Image caption A Direct Air Capture (DAC) machine installed in Iceland
Critics say this idea would need the deployment of huge amounts of land which would reduce the amount of land for agriculture at a time of increasing global population.
Another technology that has raised much interest is called Direct Air Capture (DAC), where machines pull CO2 directly from the atmosphere.
A number of experimental installations of this idea have been successfully implemented, notably in Switzerland and Canada.
But there has been little research to date on how the deployment of DAC would impact crop and food prices.
This new study looks at the large-scale deployment of a range of negative emissions technologies including DAC.
The report says that the energy and water resources needed to drive these machines will be on a very large scale.
DAC will need large amounts of heat to make the process work, say the authors. This would require energy equal to 115% of current global natural gas consumption.
https://www.bbc.co.uk/news/science-environment-53891414
In any sane world, this would put an end to the whole idea of removing CO2 from the atmosphere.