There were two main takeaways from the Global Future Cement Conference that took place in Brussels last week. Firstly, there are not any obvious alternatives to using cement and concrete. Secondly, serious at-scale commercial investment on capturing CO2 process emissions from clinker production is still waiting for the right economic conditions.
Graph 1: Embodied energy versus embodied CO2 of building materials. Source: Hammond & Jones, University of Bath, UK.
Although the conference was heavily focused on Europe, the graph above explains why the cement and concrete industries are sitting pretty right now in the face of mounting environmental activism. The sector may be responsible for 5 - 10% of annual CO2 emissions but, put bluntly, there is simply no alternative. As Karen Scrivner from the Ecole Polytechnique Fédérale de Lausanne (EPFL) explained during her presentation, concrete uses some of the most abundant minerals present on earth, notably silicon and calcium. Alternative chemistries are simply not backed up by available materials. The cement and concrete associations have strongly promoted the unique position by focusing on the whole lifecycle of building materials.
The energy and emissions research needs to be scrutinised much more closely but, if it’s correct, there is no way to maintain modern standards of living without concrete. And, judging from the response by the French public to a badly handled meagre carbon tax on diesel by the so-called Yellow Vest movement, whacking up the price of housing or infrastructure might go down badly, especially in developing countries.
Two immediate ‘outs’ presents themselves. Cement doesn't necessarily have to be made from clinker as Robert McCaffrey’s presentation reinforced (also given at the IEEE/IAS-PCA Cement Conference this year). Future research may find alternatives to clinker and wipe out the cement business in the process. Also, the graph above is based on per kilogramme amounts of each building material. It doesn’t indicate how much of each material is required to build things. Even if clinker-based building materials are irreplaceable, there is no reason why their market share might not decrease. This could have large consequences in a market already burdened by over-capacity.
Graph 2: Comparison of cost of carbon capture technology for the cement industry. Source: European Cement Research Academy (ECRA).
Solid research into carbon capture technology is proceeding apace, from the LEILAC project at HeidelbergCement’s Lixhe plant, to oxyfuel kiln development and other methods, as Jan Theulen from HeidelbergCement demonstrated in his presentation. Off-the-shelf technologies from other industries also exist ready to be used. Today, for example, Inventys has announced plans to test its own CO2 capture technology with Lafarge Canada. Yet there are no commercial-scale installations in Europe. most likely due to the price burden it would place on the end product.
With the European Union (EU) Emissions Trading Scheme (ETS) entering its fourth phase and the carbon price holding above Euro20/t the question is: when will the serious investment begin in Europe? Notably, more than a few major European cement equipment manufacturers attended the Global Future Cement Conference, yet none are offering mature products to capture CO2 emissions. Most or all have projects up their sleeves ready to be developed and sold but orders aren’t being received. The carbon price in Europe is the problem here. If it's too low then nothing happens outside of government subsidy. Too high and cement plants start being shut down because they become too expensive to run. To be fair to the cement sector other carbon emission mitigation strategies are being employed from alternative fuels usage to lowering the clinker factor and other methods but the endgame is based on reducing process emissions.
The challenge for the cement and concrete industry is to show legislators that their materials are essential and irreplaceable. They are doing this. The legislators then need to concoct ways of encouraging mass scale rollout of carbon emissions abatement technology without destroying the cement industry. This is far from certain right now. If nothing else it’s in governments’ interest to get this right because, as the Yellow Vest protests show, if they get it wrong their voters become angry. All of this is happening against the clock as CCU/S is required to get the cement industry past the 2050 2°C maximum warming target set by the Paris Agreement. In the meantime the cement industry is essentially in a holding position on the more far-reaching aspects of CO2 emissions mitigation. Its products are likely irreplaceable but its carbon capture technology has to be encouraged by governments. This means that, for most cement producers, waiting to see what happens next is the way forward.
The 3rd Future Cement Conference and Exhibition is scheduled to take place in Vienna, Austria in 2021