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November 2021

As I write, the UN climate change conference, COP26 is taking place in Glasgow and the pressing need to decarbonise our economies is being made loud and clear.

Over the last 100 years the CO2 levels in the earth’s atmosphere have rapidly increased from a long term average of 280 ppm (stable over millennia) to a current level of 414 ppm1. Given that CO2 is known to absorb IR radiation (heat), good science and common sense dictates that we try to reduce carbon emissions. Engineering is clearly central to this task and lies at the heart of efforts to revolutionise future energy use and application, to bring electrification to all aspects of our lives, in power generation, heating our homes and providing transport.

Blog-port-talbot-steelworks.jpgWhilst headline stories tend to focus on electric cars, the role of air travel and other such personal aspects of our economy, the industrial production methods driving manufacturing of goods are also extremely important in tackling carbon emissions. Many reductions made in the advanced economies of the west are due to offshoring of production to the far east, thus the site of carbon emission gets moved but the amount remains unaltered. For example, China is responsible for > ¼ of global emissions2 but also manufactures ~ 30% of the world’s goods3.

Looking closer to home, companies in Wales produced 18.8% of all UK carbon emissions from major industries, despite the country only having ~ 5% of the UK population. A recent BBC Wales analysis of official emissions data from 2019 shows major Welsh industries pumped out the equivalent of more than 23.5 million tonnes of climate-warming gases. The emissions total for Wales was reported at 42 MTonnes CO2 equivalent in 20174, and so industrial sources are a major component of the nation’s carbon budget. The good news here is that focused efforts on a few sites with large emission levels can bring huge rewards.

Blog - Eng carbon reduction.pngTo discuss this with an expert in the field I met with Dr Ian Mabbett, an Associate Professor at Swansea University who is developing transdisciplinary research and systems approaches to unpick global challenges, including climate change. Ian is involved with projects such as SPECIFIC (www.Specific.eu.com) – whose vision is a world in which ‘Active Buildings’ can generate, store and release their own heat and electricity from solar energy; and SUNRISE (www.Sunrisenetwork.org ) - an international project working with partners in India to address global energy poverty through developing photovoltaic technologies.

I began by asking Ian to introduce himself and his interests on tackling climate change:

Blog - Ian Mabbett.jpg

I’ve found myself really going on a journey of discovery as my career has developed. I began working on how to speed up industrial processes and from there migrated to energy materials. During this I started to look at systems in developing nations and everything came together around the Sunrise project and work involving the global south and engagement with communities.

In coming back to climate change we’ve begun to realise that you cannot just have one approach and you have to think in a systems way – for example, from an engineering perspective we have to ask how our sanitation works together with water supply and energy systems and how all of these interface with food production and supply chains. Of course this means that the challenge becomes massively complex and then even more complex when we think about how to get people to engage with all of this.

In a Welsh context this translates to how we create an industrial decarbonisation network here and how we link that to Wales in general so that it goes beyond industrial processes into buildings, transport and influences people’s lives and jobs.

Given the discussion, and often argument, over different countries’ roles in emitting carbon and the historical dimension to this, how do you see the global dimension and trade-off’s in developing net zero technologies?

Of course this is where COP26 comes in and where the West can be slightly self-righteous. If you look at China and India yes, they are high emitters, but they are also the world’s factories now. So, if for example, we closed Tata steel at Port Talbot tomorrow, we’d drastically reduce Wales’s emissions but we would still be using the steel.  The global aspect is exciting though as it gives us a chance to try lots of different solutions - in our projects with India, particularly rural India, cost obviously becomes really critical and the ability to manufacture things there, you need to resource high abundance, low cost materials. But you also have a blank piece of paper for things, so for instance you can move away from a built-in assumption of a national power grid that has become the default model in the developed world and build micro-grids. This is especially true in island nations, like the Maldives for example, where emissions per capita have been low historically, yet they face some of the largest and most immediate climate risks. Wales is exciting because of its scale which gives us a great opportunity to be a pilot-project nation, we can build solutions here and then look to spread them to other nations.

It certainly seems that in Wales we do have a lot of momentum, backed up by political commitment, to make substantial change:

Yes, we’ve got a really interesting policy landscape, things like the Wellbeing of Future Generations Act which the UN has recognised as ground-breaking and the new school’s curriculum for Wales which has a vision behind it that is probably exactly what we need.

Looking at the predominance of large industrial plants in the make-up of carbon emissions in Wales, industrial decarbonisation does give us the opportunity to make gains:

Yes, and this is something that people don’t always get their head around when thinking about carbon reduction. If you look at aviation for example, in global terms it accounts for a small fraction of carbon emissions and it skews the debate a little bit in that people may feel good because they haven’t flown anywhere but in reality, are still producing carbon in other ways. So the messaging here perhaps need to change. Again there is an opportunity here as most messaging at the moment is dystopian and sees us headed to a ‘mad max’ type world, this makes people anxious and defeatist about the challenge. If we give a positive message of hope, then as scientists and engineers we have a stimulus to make a better future.

So looking to a hopeful future of decarbonised manufacturing what specific technologies are being considered?

Well there are quite a few and that’s one of the big challenges in that there is such a broad sweep of possibilities. Making choices on fuel switching to greener energy is, I guess, the primary step and then of course we have to source these alternatives. Again though we need to think in a system way, take Hydrogen for example, it has a lot of potential benefits, indeed I’m a supporter of its place in future systems. However, it’s not without its own issues. So called ‘blue hydrogen’, seen by many as a stop gap, is essentially a thermodynamically unfavourable way of using natural gas. You make hydrogen by steam reforming methane. ‘Green hydrogen’ is the ultimate goal, produced by renewables through water splitting, but on a global scale we must remember that many communities are water constrained and we don’t yet have all the renewable capacity we need. From a round trip efficiency perspective you have to factor in desalination and deionisation, electrolysis and then compression for storage, whilst ensuring compatibility with all the materials it comes into contact with along its journey. This is exactly why we have to think in systems terms. The biggest benefit is that it only releases water vapour, but even then we must be careful; anyone who has been out on a clear night knows that it is colder than on a cloudy night as that cloud is trapping heat!

We really need as well to look at the efficiency of our processes. In steel making we need to think about how we recover waste gases, and again we need to think about the complete process. We will still need carbon-based materials, so carbon capture and utilisation, mixed with bio-derived materials and bio-refining can avoid us having to go back to crude oil to source everything we make from petrochemicals. At the moment we might pass the gases through a scrubber, but this cools everything down and we lose all that energy and then have to add additional energy later in the process. So this leads us to think about what can we do with hot chemistry? We are also looking at the question of intensity alongside efficiency – e.g. can you run a blast furnace for 2 minutes instead of 5 hours?

With all of this we need to consider the circular economy and the idea of industrial symbiosis.

Finally, what inspired you to become a scientist and technologist?

I was always interested in science, and I’ve come to realise this is because I’ve never grown out of asking why? As an undergraduate student I spent a year in industry researching the resin on sandpaper! And the whole thing began to look different to me – if that much thought and effort goes into what sandpaper resin does then the scope science and engineering is suddenly much bigger.

Later on I found I enjoyed research so much that I’ve made sure I’ve continued with it, whilst interacting with industry as well.



1 U.S. National Oceanic and Atmospheric Administration

2 Earth Syst. Sci. Data, 12, 3269–3340, 2020

3 United Nations Statistics Division

4 Welsh Government - StatsWales