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Removing carbon from the atmosphere, or stop it from getting there in the first place?

I have the pleasure of introducing Fabian as the guest writer for this week's blog. Fabian is currently completing the same Bachelor's degree at LSE that I graduated from (5 years ago!) and is really making the most of it.


This all started after a fascinating conversation over coffee a few weeks ago about negative carbon and using sequestered emissions for industrial processes. We explored the commercial benefit of it as well as the obvious environmental need. Without further ado, over to Fabian below.


My interest in carbon capture and storage, and carbon dioxide removal (CCS and CDR from here on out), spiked when my professor at the London School of Economics highlighted that the amount of atmospheric CO2 reduction needed to stay below 1.5°C must be negative, not neutral or flatten, by 2050.

I was shocked to learn that even if the entire world switched to renewables overnight, there would still be far too much atmospheric carbon dioxide to stay under the UN’s targets for climate change.

Demonstrated in the diagram below, the only way to stay under 1.5°C of climate change is to pull carbon dioxide out of the atmosphere. That’s where CDR, and to an extent CCS, comes in.

Currently, it takes massive amounts of energy to pull CO2 out of the atmosphere, not to mention the double negative of deforestation, Earth’s natural CDR project, so finding commercial applications for CDR is difficult. However, below are some areas where strides are already being taken to commercialise CDR and CSS and its intensive processes.

Firstly, let’s start by defining CDR and CSS as two unique approaches to limiting atmospheric CO2.

CDR

Carbon dioxide removal, refers to the removal of anthropogenic emissions by human innovation or ingenuity.

The basics methods of CDR are planting trees that naturally absorb and store CO2, known as a carbon sink. However, human innovative approaches, or ‘negative emissions technologies’, are still in relative infancy.

When people think of CDR they tend to associate it with Direct Air Capture, which is the perceived ‘holy grail’ of CO2 removal strategies. Carbon Engineering, a company backed by Bill Gates, has developed a method of literally sucking CO2 out of the atmosphere. One Carbon Engineering plant, using giant fans and complex chemical processes, does the work of 40 million trees. This is a truly negative carbon technology.

However, it is not without its flaws. Carbon Engineering have partnered directly with some of the largest emitters in the world, the Supermajors of the Oil & Gas industry.

Some experts believe this partnership will give the largest emitters a ‘free pass’ to continue pumping CO2 into the atmosphere with the hopes of commercialising the direct air capture technology in the future.

One plant may be equivalent to 40 million trees, but just to put this in context, there are an estimated 3 trillion trees on Earth. A quick calculation tells me we’d need 75,000 of these plants to match the sequestration capacity of the world’s natural CDR process. That’s double the amount of McDonald’s restaurants globally.

CCS

Arguably more controversial, the Carbon Capture and Storage approach is very simply putting a lid on coal fired power stations and burying that captured CO2 deep underground where it will be stored again acting as a ‘carbon sink’, or used for processes discussed below.

This technology is not additional, it is not carbon negative, it is arguably carbon neutral, but more likely it will still lead to a longer time horizon of relying on fossil fuel generation. Larger plants will remain open on the notion that they may adopt CCS technology in the future when it becomes affordable, rather than switching to a renewable solution.

Nevertheless, we are still heavily reliant (over 85% of energy generation) on fossil fuels, and therefore an intermediary solution to capture that carbon is essential.

It is worth noting, that if the technology is implemented at a biomass power plant, it would technically be carbon negative. Providing the biomass is from sustainable forests, the burned woodchips would not emit the majority of the carbon sequestered over the lifetime of that particular forest, therefore the carbon sequestration would be additional.

Agriculture

CO2 has already long been used to fuel plant growth in greenhouses, moreover an interesting large-scale project is being done in the USA, turning captured carbon into fertiliser. Wabash Valley Resources is turning captured carbon dioxide into ammonia, a key fertiliser, to sell to local farmers. The reason this holds a lot of potential is because fertiliser plants comprise 2% of all global greenhouse gas emissions.

Industry

The potential for carbon capture in industry is near limitless, from aggregates to chemicals, captured carbon has the potential for wide-scale use in industrial processes. TATA is already investing £16.7 million into a carbon capture plant, or CDR plant similar to the Carbon Engineering prototype, in order to create sodium bicarbonate, a common ingredient in pharmaceuticals and food.

There are also a number of companies creating aggregates and construction materials from captured carbon dioxide. This offers a promising application of carbon capture not only because the carbon is sequestered and stored for long periods of time, but because it’s the least energy intensive application of carbon dioxide, overcoming a serious economic and environmental hurdle.

The Hydrogen Economy

The hydrogen economy, I believe, is the most fascinating area for carbon capture development. While the cross-over between carbon capture and the hydrogen economy is a very new area of study, promising research from UNIST, South Korea, has found a way to turn captured carbon into hydrogen using electrolysis. This process is demonstrated below.

Pairing carbon capture with the hydrogen economy could pull huge amounts of CO2 out of the atmosphere because of the huge, future level of demand and the need to regularly refuel. Just recently, a study found that 99% of all container ships crossing the pacific, could be powered by hydrogen, if this hydrogen was created using carbon capture then we would see a paradigm shift in the shipping industry, often seen as the leading polluter.

However, this new fuel economy hasn’t arrived just yet, so in order to create this effective relationship, investment into the hydrogen network must come first.

The Main Problem Facing CDR and Carbon Capture

The current price for carbon is about $25 per metric ton (under the emissions trading scheme) while it costs about $100-$200 to extract a metric ton of CO2 from the atmosphere (as of 2018). If governments really want to incentivise carbon captures schemes, the price of carbon must be raised significantly.

Nevertheless, the future looks bright for the atmosphere due to the promising forecasts of CDR and carbon capture. McKinsey & Company estimates that by 2030 CO2-based products could be worth between $800 billion - $1 trillion, and the use and application of CO2 could reduce greenhouse gas emissions by a billion metric tons annually

Final Thoughts

Commercialising carbon capture and CDR is a multi-faceted challenge, but if surmounted, there are many practical ways, as demonstrated above, that we can utilise this untapped resource.

For me personally, I’m most interested in the future relationship between carbon capture and hydrogen, because in a post-fossil fuel world, meeting the demand for hydrogen with captured carbon could be a game changing partnership and would help us remain within the 1.5 degree IPCC forecast.

Sources

Wabbash Valley Resources Turning CO2 into Ammonia

https://www.feedstuffs.com/news/largest-carbon-capture-sequestration-project-produces-ammonia

TATA installing £16.7 million carbon capture project

https://www.ft.com/content/b45d94b6-97fc-11e9-8cfb-30c211dcd229

UNIST Researchers turn captured CO2 into hydrogen

https://www.sciencedirect.com/science/article/pii/S258900421830186X#!

Hydrogen 'can power virtually all container ships crossing the Pacific'

https://www.rechargenews.com/transition/hydrogen-can-power-virtually-all-container-ships-crossing-the-pacific/2-1-767073

Carbon priced at $25 under EMS

https://www.en-former.com/en/metric-ton-co2-cost/

Carbon costs $100-$200 to extract a metric ton

https://www.environmentalleader.com/2018/06/carbon-capture-technology/

Mckinsey and Company’s predictions for the future of carbon capture

https://blogs.ei.columbia.edu/2019/05/29/co2-utilization-profits/

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