The self-price elasticities of demand are fairly well-defined, at around -0.20 for ε !",!" 31 and -0.18 for steel. It is generally assumed that the two cross-price elasticities (ε !",$%&&" and ε $%&&",!" ) are the same, and we use an estimate The hydrogen cost is for hydrogen produced from electrolysis. The emissions intensity of coal, natural gas, and the petcoke-based carbon anode for aluminum are known. The grid emissions intensity of electricity varies widely with geographic location and electricity source. The value shown is the US average from 2021, per the EIA. The hydrogen emissions intensity assumes US average electricity grid intensity, with an electrolyzer eDiciency of 0.75.