Climate Action and Green Hydrogen (GH)
Climate action involves complex transformations, with green hydrogen (GH) being a promising solution amidst the hype. A scientific perspective over hype is crucial.
Thermodynamics and Energy Efficiency
- Electricity is highly efficient for applications like scooters and cars, with 90% energy conversion, unlike internal combustion engines at less than 20%.
- Hydrogen becomes vital where electricity can't be used directly, such as in steel plants or giant cargo ships, which account for 20-30% of CO2 emissions that cannot be reduced through electric power.
- Renewable energy (RE) for GH should come from incremental capacity, not from existing capacity.
India's Hydrogen Policy and Targets
- India aims for 125 GW for generating 5 million tonnes of GH, in addition to the 500 GW target by 2030.
- Current GH costs are about $5/kg, needing reduction to below $1.50/kg for commercial viability.
Energy Security and Electrolyser Production
- India must avoid substituting fossil fuel with electrolyser dependence by producing a significant share domestically at lower costs.
- The government invested over $2 billion in domestic electrolyser manufacturing.
- Hydrogen leakage poses a risk, capturing 37 times more heat than CO2 over 20 years, potentially reducing climate benefits by up to 25%.
GHG Emissions and System-Wide Impact
- If RE for GH is not additional, electricity might be replaced by natural gas or coal, increasing warming by a factor of 3-4.
- Minimizing transportation, monitoring leakages, and engineering improvements are needed to mitigate leakages.
Export Potential of Green Hydrogen
- Export potential to countries like Japan, sub-Saharan Africa, and Southeast Asia where RE costs are higher or capacity is lower.
- Theoretical potential exists but threatened by leakage risks offsetting climate benefits.
Overall, India holds environmental, economic, and strategic advantages in pursuing green hydrogen within the outlined considerations.
