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In defence of gasification

Engagement Manager

Assessing the sustainability of new technologies: can we ever find one perfect solution or will it always remain a grey area? 

I am now almost fourth months into working at RIG, so the time has come for me to contribute a blog. I knew immediately that I wanted to discuss an area that I hadn’t initially predicted as a challenge: the lack of black-and-white opinions on sustainable technology. The first technology I have had the pleasure of working with is a gasification technology processing municipal solid waste (MSW). The immediate question that comes to mind is ‘what is gasification?’ The easiest comparison is to incineration: during incineration, combustion is carried out with large amounts of oxygen, producing heat which is used to power a steam turbine generator, producing electricity and heat. With gasification, the waste is processed in a high-pressure, low-oxygen environment to produce a synthetic gas (a syngas composed primarily of carbon monoxide and hydrogen), which can then be used to produce heat or electricity or upgraded to produce higher-value products such as advanced fuels (e.g. hydrogen, biodiesel, ammonia, methanol, etc.).

I was interested to learn that the technology was somewhat divisive, with some authors arguing that gasification discourages reducing and recycling waste and poses significant risks based on previous failures with the technology –  these risks are centred around the challenges of processing waste economically and achieving contracted operating hours, processing a non-homogenous feedstock (i.e. MSW) and mitigating various technical issues. Due to the plastics in MSW, it is also argued that this is not a ‘green’ feedstock since it is partially fossil-based; though turning waste into advanced fuels via gasification produces less CO2 and pollutants than incineration, CO2 is still being released due to the plastic content, which is detrimental given the urgent need to reduce global emissions.

Yet there are two sides to every story. The advanced fuels produced are intended to assist in defossilising the transport sector which contributes a significant percentage of global emissions (making up 16.2% of global emissions in 20201). Whilst there are solutions such as electric vehicles (EVs) already being rolled out, shipping, aviation and long-haul trucking are significantly harder to decarbonise, partly since many of the necessary technologies (e.g. solar-powered jet engines or hydrogen fuel cells) are not yet commercially available. For these hard-to-decarbonise areas, hydrogen is seen as an area of great potential.. Despite this global interest (with 50 targets and policy incentives that directly support hydrogen in place as of 2019, the majority of which were focused on transport2), it is not yet cost-effective to produce hydrogen renewably; as of 2019, 95% of hydrogen was produced from fossil sources3. In comparison, gasification is able to produce defossilised hydrogen and advanced fuels at competitive costs now. Thus, whilst the process of commercialising the above technologies is carried out, the use of defossilised, circular fuels remains better than the status quo.

One point to highlight from the above is the use of the word defossilisation rather than decarbonisation. As MSW will have a fossil-based fraction until plastics etc. are removed from our day-to-day lives, it is true that these fuels are partly fossil-based. Although they contribute to a circular economy by upgrading the usefulness of our waste and reducing our dependence on fossil fuels, it cannot be said that they are decarbonised fuels. This leads me to the subject of the counterfactual – considering the emissions offset on both sides of the value chain. Whilst, in accordance with the EU waste hierarchy, prevention, reduction, reuse and recycling always should and will be the priority, this change will not happen overnight. Therefore, alongside pushing for these changes, we should also be looking to optimise recovery processes; comparing gasification to incineration (specifically in the case of advanced fuels), optimised gasification technology is able to offset a larger percentage of emissions than existing incinerators.  

The final topic often discussed in this context is CCUS – why develop alternative solutions to incineration when you could just capture the carbon produced? Unfortunately, it is not yet at a stage where it can be universally rolled out, with challenges still to overcome (such as the need for investment into pipeline infrastructure) to see widespread adoption of the technology. Therefore, although there is significant value in the technology, it can’t be relied on to instantly resolve the industry’s problems; so, whilst the technology is being developed, we should continue to push for better solutions than the status quo.

So what are my thoughts four months later? There is not a silver bullet that will solve the world’s problems. We need to continue to push for technological improvements compared to the status quo, even if the replacement technology is not perfect – and whilst doing so, we need to simultaneously push for societal change (reducing waste and plastic use and increasing recycling) to address the root of the problems. Working towards resolving the climate crisis will require a multitude of solutions (technical or otherwise) – and for now, I’m just grateful to be working on one.