- intro – need to shift to cleaner technologies.
- Mention the types of Hydrogen available.
- Discuss the challenges associated with “green” hydrogen.
- In conclusion, mention India’s opportunities.
To meet its Paris targets, the world needs to shift focus to more difficult options like hydrogen, direct carbon capture and carbon capture, utilization and storage (CCUS). Unless these new technologies are adopted, it is hard to abate climate change.
Hydrogen have different forms – “green” hydrogen is derived through electrolysis of water using renewable energy sources for generating electricity. Hydrogen from fossil fuels is either “brown” or ‘grey” depending upon whether it is coal or gas based. “blue” hydrogen is produced from fossil fuels, but part of the C is absorbed using CCUS technology. Today, less than 1% of the world’s hydrogen is “green”.
- Hydrogen from fossil fuels costs between $1 – $2 per kg, compared to “green hydrogen” costs of $4 – $6 per kg – thus expensive. It is expected that green hydrogen will become competitive by 2030 as the cost of electrolysis is deemed to come down. Also, efficiency is expected to improve.
- Converting electricity to hydrogen, shipping it, storing it, and then converting back to electricity will deliver energy below 30%. Also, this will need huge electricity from renewable sources which will put pressure on land.
- Transporting hydrogen is problematic. While H has a very high energy content per unit mass compared to natural gas, its energy density is low per unit volume. This implies need for huge containers to transport H having equivalent energy content.
- Converting H to liquid form to facilitate transportation will require cooling to – 253 degree Celsius and then reconverting will require lots of energy. Converting to H-based fuels before transportation will require additional energy.
- Using electricity from grid is fossil-fuel based, which will negate the entire purpose of producing green H.
- Existing pipelines can be used for transportation, however, there are limits to the distance hydrogen can be transported. Worldwide, about 85% of green H is produced “on-site”.
- Hydrogen has limitations in certain sectors – while it is best suited to industrial sector, it has restricted use in transport & power. It is not compatible for smaller distances fuel cells, but useful in long-distance transportation where batteries have low energy-to-weight ratios. It is also good for storage in power sectors, which is ideal for inter-seasonal storage and over several weeks/months.
- It is not always economically viable to produce “green” H.
Acc. to TERI, the demand for green H is expected to increase in India from 6 MT today to 50 MT by 2050. Also, India is ideally placed for making “green” H domestically. India has the advantage of producing cheap electricity from renewable sources and thus, have the potential to become hydrogen exporter. A roadmap needs to be drawn in R&D to lower cost of electrolysers and make India manufacturing hub. Standards should be laid down for large scale use of H, besides framing safety regulations. The recent Hydrogen Mission is an important step in that direction.