Anthropogenic activity has increased carbon dioxide (CO2) concentrations in the atmosphere to unprecedented levels; approximately 414 parts per million just last year. Fossil fuel consumption for electricity, transport, heating and industry contributes 3.7 gigatons of CO2 annually. Consequently, global warming devastates our climate, demonstrated recently by heat waves in Europe and flooding in South Asia. Limiting the rise in the Earth’s temperature to 2 degrees Celsius will be a herculean task, requiring determined action to achieve net Carbon zero emissions. This may be achievable if we systemically decarbonize each industry gradually. One sector is the steel and iron industry, which contributes to 9% of CO2 emissions. With existing technology, Steel production requires substantial quantities of carbon, obtained from Coal, in the chemical process. Production occurs in 2 steps – Iron Ore is ‘smelted’ to create Pig Iron. Then oxygen is bubbled through the melting Pig Iron in a blast furnace. This results in oxidization, removing excess carbon. Around 75% of steel is made in coal-fired blast furnaces. 1 Ton of Steel produces 1.85 Tons of CO2 – 1,951 Million Tons of steel equates to 3609.35 Million Tons of CO2. Decarbonizing this process is conceivable and would require supplanting carbon/carbon monoxide with another gas such as hydrogen. Using hydrogen would produce water vapour, eliminating the production of CO2 and reducing carbon emissions. However, commercial and industrial hydrogen is produced in limited quantities by Steam Reforming i.e. reacting Natural Gas with high-temperature steam. If the price of Natural Gas rises then this process becomes too expensive. There is an alternative solution – producing Green Hydrogen by electrolysis. Electricity is passed through water to produce oxygen and hydrogen. The electricity for this process may come from renewable sources e.g. Wind or Solar Power. Typically an expensive process, the production cost of green hydrogen has decreased by 60% – from 3.6 to 5.3 Euros / Kg. This price is anticipated to fall further to 1.8 Euros / Kg, as investment costs of facilities dwindle due to mass adoption and the costs of renewable energy continue to decrease – or even half by 2030. We would require an estimated 53 kWh of electricity to produce 1 Kg of Hydrogen, and 50 Kg of Hydrogen for 1 Ton of Steel. A timely shift from carbon to hydrogen in the steel industry will require coordinated action. Again, the problem is pricing – 1 Ton of Steel costs roughly 400 Euros, including 50 Euros for Coal. Replacing Coal with Hydrogen at current prices (3.6 Euros / Kg) would necessitate 180 Euros worth of Hydrogen, increasing total costs by 32.5%. However, if projections for the fall in Hydrogen prices are correct then this process becomes economically viable. There is some good news; the EU has undertaken bold initiatives to establish pilot plants in Austria, Sweden and Germany that utilize the hydrogen-based route, enabling operators to gain expertise. Scaling up this scheme would require establishing new hydrogen production facilities at an unprecedented scale, and producing hydrogen at the lowest cost. Achieving this would warrant the shift away from traditional methods of steel production. Additional efforts are underway to experiment with these strategies. Larsen & Toubro has commissioned an 800 Kw Green Hydrogen plant in Gujarat, India to produce 45 Kg of Hydrogen daily. Tata Steel has partnered with Canadian firm Hatch to adopt CRISP+ furnace technology in plants in the Netherlands for the production of green steel. By 2045, Tata hopes to convert all of its steel mills to the ‘green’ hydrogen-based route, phasing out coal and carbon dioxide in steel production. Accelor Mittal Europe has also publicized its plan – producing 30,000 tons of green steel in Germany, scaling up to 600,000 Tonnes in a few years and eventually achieving net carbon zero in all of its facilities by 2050, at $40 Billion. The lessons learnt from these pilot projects will be essential if we wish to decarbonize the steel industry. These projects could optimize this technology’s efficiency and safety by the middle of the decade, followed up by demonstration projects at a commercial scale by 2030. At that point, the price of green hydrogen will likely have decreased so much that hydrogen-based steel production may also be economically advantageous. A timely shift from carbon to hydrogen in the steel industry will require coordinated action in a wide array of sectors. We would have to reduce the costs of producing hydrogen, resolving the supply side of the equation and ‘encourage’ steel manufacturers to adopt these processes through tax cuts and carbon credits, resolving the issue on the demand side. Initially, the cost of steel production would rise but with time, as mass production of green hydrogen kicks in and renewable energy prices drop further, the process may even become cheaper than the coal and carbon dioxide process. The writer is a freelance columnist.