Kjell, for the rebar Tally baseline, are you using the CRSI Fabricated Steel Reinforcement EPD? That would be a baseline of 0.98 MTCO2e/MT. The 1.48 MTCO2e/MT value looks like it’s from MBMA’s Primary Structural Steel Frame Components EPD. The CRSI EPD is what CLF is adjusting to the 2 MTCO2e/MT.
If we compare the unadjusted CRSI EPD to the unadjusted Nucor Seattle EPD, we’ll see a reduction of 50%. Now the 69% reduction using the CLF method does start to look different.
That’s one of my questions - in such industry vs product comparisons - does the CLF methodology artificially inflate the CO2e savings by penalizing the industry-wide EPD for more uncertainty?
My other concern is about the absolute numbers which will get inflated upon using the CLF methodology. Right now for our core-and-shell LCAs, take offices for example, we’re seeing a GWP intensity of ~500 kgCO2e/m2 for optimized buildings, and ~630 kgCO2e/m2 for baseline buildings. If we add in uncertainty-adjustments, these may go up by 20-50%. This might then create issues when comparing against absolute benchmarks, such as ILFI Zero Carbon’s maximum of 500 kgCO2e/m2. Or even comparing embodied carbon to operational carbon. Although perhaps these aren’t ‘issues’, they’re now ‘truer’ reflections by adding in the uncertainty.