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Electricity is needed as an energy input to the In short, CCS technologies are mandatory to produce
water electrolysis process, and electricity can be clean Hydrogen, and renewable-based water
economically produced using renewable sources. electrolysis methods can become a financially attractive
Therefore, water electrolysis using renewable energy option for hydrogen production. This provides an
sources can produce Hydrogen and reduce carbon essential direction for research efforts in future for
footprint in hydrogen production. With technological developing hydrogen infrastructure. As Hydrogen
advancements, electricity production costs from is currently produced mainly in central processing
renewables are continuously declining, and more facilities in select industrial areas, an extensive
capacities are being added. Due to non-availability distribution network is needed for making it available
of renewable sources for 24 hours in a day, electricity across the country. Adaptation of CCS technologies
produced from renewables often has energy storage will also help in the nationwide spread of hydrogen
requirements. production locations and ensure Hydrogen availability.

Hydrogen can be used for energy storage as well. There Coal gasification process produces syngas which can
is significant scope for setting up dedicated renewable be used for power generation. CCS technologies are
electricity generation facilities for environmentally usually integrated with coal gasification units; thus, they
clean hydrogen production and storage. can produce clean electricity. Hydrogen production
from syngas (obtained from coal gasification) can be
Another way of reducing carbon dioxide emissions from enhanced using water gas shift technologies. Entire
hydrogen production processes is carbon capture and coal gasification unit can be further optimised and
sequestration (CCS) technologies. Natural gas-based or configured for a flexible switch between electricity
coal-based hydrogen production processes can amend generation and hydrogen production.
the techniques to capture carbon dioxide.
Biomass is another alternative source for hydrogen
Presently, the operating costs and CAPEX production. However, the limited availability of biomass
requirements for CCS technology are high due to and higher production costs are the significant barriers
which commercialisation of technology is yet to to mass-scale commercial production. Considering the
mature. Worldwide, CCS technologies are being difficulties in hydrogen storage and transportation due
rigorously researched, and developed economies are to its low molecular weight, it can also be converted
seriously promoting research, testing, marketing and into other chemicals such as synthetic natural gas,
implementation at select locations. ammonia, jet fuel, etc. which can be used as fuels.
This may not be an economical option at current price
Hydrogen production prices vary significantly between levels.
various regions due to the variable cost of resources
used for making Hydrogen. Natural gas and coal Hydrogen Storage
are abundantly available at a lower price only in the
select areas as its availability are not uniformly spread Hydrogen has high mass-energy content but is the
over the entire world. Similarly, costs for electricity smallest molecule (Mol Wt. 2), it has very low volumetric
generation vary widely between various regions. density and low volumetric energy. This peculiar
Raw material availability hence influences the cost characteristic of Hydrogen poses difficulty in its
of hydrogen production to a great extent. Hydrogen storage. Hydrogen is highly flammable material having
production using natural gas without carbon capture a relatively more extensive range of explosion limits
technology is presently the most economical route in air. Safety aspects thus form an integral part of the
amongst all regions. Cost of hydrogen production hydrogen storage technologies.
through the electrolysis route depends on electricity
production costs and overall, these methods are Hydrogen usually is available at 1 to 4 bar pressure
currently expensive compared with the natural gas- when produced from electrolysis route and at
based production process without CCS. Suppose cost roughly 20-30 bar when created from Steam Methane
of electricity generation is between 10 US$ to 40 US$ Reforming (SMR) route. Reducing Hydrogen’s volume
and considering full load hours of 3000 – 6000 per for transportation is achieved by increasing its density
annum. In that case, hydrogen production from water by compressing Hydrogen to a higher-pressure level
electrolysis can be cost-competitive compared to the and then storing in pressurised cylinders before
production based on natural gas processes with CCS. transport.

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