Why low-carbon cement isn’t enough
Cement accounts for 8% of global carbon emissions. Low carbon cements are a step in the right direction but a focus on carbon savings alone will not save the world. There are several other concerns with the construction industry that need to be addressed in tandem. The sector needs to revisit its consumption of primary materials for many reasons. Aggregates (sand and gravel) make up 60 - 75% of the volume of any concrete mix and low carbon cements still do not address the current overconsumption of these materials. In addition to concrete, flat glass - the kind of glass that is used to make glass panes, and other architectural glass, contains about 70% of silica sand. Also, vast tracts of precious coastal forests, some of which are endemic, old-growth forests, are being razed to the ground in order to source heavy mineral sands that yield minerals that go into paints and plastics. The built environment sector consumes 50% of all raw materials mined and harvested annually. It is time for this industry and its suppliers to radically reinvent themselves. Recent research has shown that ‘The 20th century saw a 23-fold increase in natural resources used for building’. The year 2020 marked the crossover point, when the Anthropogenic mass (concrete, asphalt, metals etc.) surpassed the amount of Biomass (the mass of all living things) on Earth. ‘Humanity has become a dominant force in shaping the face of the Earth.’
Key impacts on local communities and the environment are unfortunately still treated as mere ‘negative externalities’ and extractive industries rarely address ‘cumulative impact’. In July 2021, Sweden’s construction industry was thrown into turmoil because its largest cement factory was denied permission by the country’s Supreme Land and Environmental Court to continue mining limestone beyond 31st October. If the ruling stands, it means the factory would have to shut down by November 2021. Some say that could have wide-ranging impacts on the economy and employment in Sweden. The Swedish steel industry stands to be affected too because cement is used to stabilize underground mines. Others think that the cement industry’s claims are overblown and ‘should be taken with a pinch of salt’. Nonetheless, that the ruling came as a nasty surprise to some (more here and here) speaks volumes and demonstrates that the construction industry and allied extractive industries need to pay more attention to socio-environmental justice if they hope to maintain the social licence to operate. Mining limestone for cement has a massive impact. In many regions, it is dismantling nature’s ecosystem services (e.g. groundwater provisioning, habitat for critical pollinators and other wildlife) and destroying the lives and livelihoods of indigenous communities. But there’s also growing awareness and expanding movements of cross-border solidarity especially with regard to the action of multi-national corporations.
The decision to turn down the cement company’s application to continue mining limestone in Slite, Gotland came after several organisations including the Swedish Environmental Protection Agency (Naturvårdsverket), Gotland’s Botanical Association, the County Administrative Board of Gotland, and the Swedish Society for Nature Conservation (Naturskyddsföreningen) appealed the mining consent. This particular cement plant was meant to be Sweden’s first carbon-neutral plant. The plan was to capture carbon and transport it for storage in Norway under the North Sea in old oil fields, 3,000 meters below sea level. It is unclear what happens to these plans. But to put carbon capture and storage into the current global context, a coalition of 500 international, US, and Canadian organizations have sent an open letter to policymakers, calling on them to reject carbon capture and storage schemes as they are ‘unnecessary, ineffective, exceptionally risky, and at odds with a just energy transition and the principles of environmental justice.’ In the UK, key progressive industry leaders see the decision by the Swedish Court as a landmark decision. They suggest ‘cement-makers should see this as a warning that EU legislators are no longer willing to support industries that drive climate change.’ Could this serve as a useful example elsewhere too?
