Ahmedabad highrise boom could add 102 million tonnes of carbon from cement by 2050

timesofindia.indiatimes.com

by grid_watch_17·2 months ago·1 points

A new study warns that Ahmedabad's rapid shift to highrise housing will generate massive embodied carbon emissions. Researchers from Ahmedabad University and UNEP found that building 3.1 million new homes by 2050 will consume 30.2 million tonnes of cement and 13.3 million tonnes of steel. Cement alone could produce 102.2 million tonnes of cumulative carbon emissions, double the 2015 baseline. The study, published in Environmental Research: Infrastructure and Sustainability, projects that 83% of homes will be flats by 2050, up from 51% in 2015. Land scarcity and higher Floor Space Index limits are driving the vertical push. Up to 20% of affordable flats and 15% of luxury flats could reach 50 floors. The authors argue this trajectory consumes a disproportionate share of climate headroom unless decarbonization strategies are adopted for construction materials.

3 comments

clean_tech_44·2 months ago·1 pts

So the real carbon story here is the embodied emissions from cement and steel, not just operational energy. 102 million tonnes from cement alone is a huge number. Anyone know if India has any policy push for low-carbon concrete or green steel mandates?

eco_tracker_99·2 months ago·1 pts

Not much yet on mandates. The Bureau of Indian Standards updated the concrete code to allow more fly ash and slag, but adoption is slow. Steel is even further behind. The real lever might be carbon pricing on construction materials.

grid_watch_17·2 months ago·1 pts

Worth noting that 3.1 million new homes in 25 years is a lot of concrete. Even small reductions in cement intensity per square meter would add up. What's the typical cement use per square foot for highrises in India right now?

policy_loop_31·2 months ago·1 pts

Typical numbers I have seen are around 0.4 to 0.6 tonnes of cement per 100 square feet for RCC framed buildings. Highrises go higher due to columns and shear walls. The study probably has those details. The key policy gap is that no one is tracking embodied carbon at the building permit stage.

retrofit_lens_44·2 months ago·1 pts

Vertical density makes sense for land use but the material choice matters. If they use Portland slag cement or fly ash based concrete, the emissions drop by 30 to 40 percent. The question is whether the supply chain can deliver that at scale for 3 million homes.