20 Dec

Hydrogen Energy

< General Studies Home Page 

Content

• Fuel cell
  • How does a fuel cell work?
  • Advantages of Hydrogen Fuel Cell
  • Limitations
• Fuel cell Electric Vehicles (FCEVS)
  • Types of Electric Vehicles
• Hydrogen Energy
  • Advantages of Hydrogen Fuel
  • National Green Hydrogen Mission
  • Government Unveils Green Hydrogen Standards 
  • Electrolysers
  • Hydrogen- CNG (H-CNG)

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Introduction

• Hydrogen is the simplest fuel. A fuel cell combines hydrogen and oxygen to produce electricity, heat and water.

Fuel Cell

• A fuel cell is a device that converts chemical potential energy (energy stored in the molecular bonds) into electrical energy.
  • A Proton Exchange Membrane (PEM) cell uses hydrogen (H2), and Oxygen (O2) as fuel.
  • The products of the reaction are water, electricity and heat.
• Key Elements of a fuel cell
  • The anode, the negative electrode of the fuel cell, conducts the electrons that are fed from the hydrogen molecule so that they can be used in the external circuit.
  • The Cathode, the positive post of the fuel cell, has channels etched into that distribute the oxygen to all surface of the catalyst. It also conducts electrons back from the external circuit to the catalyst, where they can recombine with hydrogen ion and oxygen to form water.
  • The electrolyte is a proton exchange membrane. This specially treated material, which
    looks something like ordinary kitchen plastic wrap, only conducts positively charged ions.
    The membrane blocks electrons.
  • The catalyst is a special material that facilitates the reaction of oxygen & hydrogen. It is usually made up of platinum nano particles very thinly coated onto carbon paper or clothe.

How does a fuel cell work?

• Hydrogen from a tank onboard the vehicle, enters into anode side of the fuel cell.
• Oxygen pulled from air enters from cathode side.
• As the hydrogen molecule encounters the membrane, a catalyst forces it to split into electron and proton.
  • The proton moves through fuel cell stack and the electron follows an external circuit, delivering current to the electric motor and other vehicle components.
  • At cathode side, the proton and electron join again, and they combine with oxygen to form the vehicle’s only tailpipe emission, water.

Advantages of Hydrogen Fuel Cell

• Fuel cell avoids the “thermal bottleneck” (a consequence of 2nd law of thermodynamics) and are thus inherently more efficient than combustion engines, which must first convert chemical potential energy into heat, and then mechanical energy.
• Hydrogen is high in energy.
• Fuel cells don’t have any moving part and thus are more reliable than traditional engines.
• No pollution (Only steam (H2O) emitted as by product)
• No Greenhouse gas and Climate Change (since no GHG are produced as bi-products)
• Ends dependency of Li-Ion batteries (Please note for Lithium we are almost completely import dependent)

Limitation

• Complex and difficult to build
• Still mostly in research phase
• Extracting hydrogen is difficult and expensive – catalyst used is Platinum- which is very expensive

Fuel Cell Electric Vehicles (FCEVS)

• FCEV combine hydrogen and oxygen to produce electricity which runs the motor.
  • E.gs of cars using FCEV: Toyota’s Mirai, Honda’s Clarity, and Hyundai’s Nexo.
• Since they are powered entirely by electricity, FCEVs are considered EVs, but unlike BEVs, their range and refueling processes are comparable to conventional cars and trucks.
  • The major difference between a BEV and a refueling time of just five minutes, compared to 30-45 mins charging for a BEV.
  • Also, consumers get five times better energy storage per unit volume and weight, which frees up a lot of space for other things, while allowing the rider to go farther.
• India’s first indigenously developed Hydrogen Fuel Cell (HFC) technology bus was unveiled in Aug 2023, with the fuel cell – which uses hydrogen and air to generate electricity onboard to power the bus – being developed jointly by CSIR and Pune based automotive software company KPIT Ltd (Aug 2023)

Types of Electric Vehicles: EV/BEV, HEV, PHEV, FCEV

• Electric Vehicles: The standard EV is also known as Battery powered EV (BEV):
  • They don’t have an internal combustion engine and instead of an petrol/diesel, these vehicles run solely on battery power. These can be charged at home or commercial charging stations.
• Hybrid Electric Vehicles (HEVs): They run on both Internal Combustion Engines and electric
  motor that uses energy stored in a battery. However, unlike other Evs, HEV cars battery is
  charged by regenerative braking.
  • Micro (or mild) Hybrid uses both battery and electric motor to make the car run. Though they can’t run solely on electric power, they maximize fuel economy by shutting off the internal combustion engine during complete stops.
• Plug-in Hybrid Electric Vehicles (PHEV): They expand the concept of HEVs. They have both an internal combustion engine and a battery powered electric motor. This allows the battery to store enough power to feed the electric motor and in turn decrease the gas usage by as much as 60%. They can travel around 60 kms on electric power, rather than 2-3 kms with a standard HEVs.

Hydrogen Energy

Hydrogen Energy is a clean and efficient form of energy derived from Hydrogen (H2). It has the potential to replace fossil fuels.

• Hydrogen can be produced from variety of sources including water, natural gas, and biomass.
• There are two main ways to produce Hydrogen:

1. Steam Reforming: This process uses heat and steam to break down natural gas into hydrogen and carbon mono-oxide.
2. Electrolysis: This process uses electricity to split water molecules into hydrogen and oxygen.

• Cost of producing hydrogen varies depending on the various methods used.

It can be used in two primary ways:

• Direct Burning to produce heat and water.
• Fuel Cell Route to directly produce electricity.

Advantages of Hydrogen Fuel:

• Abundance: It is the most abundant element in the Universe.
• Energy Density -> High
• Can contribute to achieving Net Zero by 2050
• No Pollution (only releases water)
• Leading options for storing energy from renewables.
• Advantages of Hydrogen Vehicles (Fuel cell Stack) over other Electric Vehicles (Lithium-ion batteries)
  • A fuel cell electric vehicle can be refueled in just 5 minutes. EV takes 30-45 minutes for charging.
  • Energy storage per unit volume and weight is higher in fuel cells than other types of electric vehicles.
  • EV battery materials are controlled by a few larger players. Scaled up hydrogen fuel cell will bring countries on equal footing.
  • EV batteries (like Lithium ion batteries) have still not been found viable for heavy vehicles like trucks.
• To get support in Regulatory Framework – the MoRTH in 2020 have issued a notification proposing amendments to the Central Motor Vehicle Rules, 1989, to include safety evaluation standards for hydrogen fuel cell-based vehicles.

Some limitations of Hydrogen fuel

• Hydrogen molecule is not available in abundance on earth and is found in combination with other elements.
  • Thus, external energy source is required to isolate hydrogen. If coal or other fossil fuel is used for this extraction, it is called grey hydrogen and has carbon footprint.
• Hydrogen technology is “yet to be scaled up”. Tesla CEO Elon Musk has called fuel cell technology “mind-bogglingly stupid”.
• Lack of fueling station infrastructure
  • There are fewer than 500 operational hydrogen stations in the world today, mostly in Europe.
• Safety is a concern.
  • Hydrogen is pressurized and stored in a cryogenic engine. Some companies like Toyota and Hyundai have said that safety and reliability of hydrogen fuel tanks is similar to that of standard CNG engines.

Note: Various types of Hydrogen: The most common element in nature is not found freely. It exists only combined with other elements and has to be extracted from naturally occurring compounds like water (which is a combination of two hydrogen atoms and one oxygen atom). This process is energy intensive.

• Grey Hydrogen
  • Hydrogen produced from fossil fuels. This constitutes a bulk of hydrogen produced today.
• Blue Hydrogen
  • Hydrogen generated from fossil fuels with carbon capture and storage options.
• Green Hydrogen
• Hydrogen generated entirely from renewable power sources. Here electricity generated from renewable energy is used to split water into hydrogen and oxygen.
• For e.g., a IIT-Madras team generated hydrogen from seawater using solar energy. (June 2023)

National Green Hydrogen Mission

Ministry: MNRE

With a vision to make India an energy independent nation, and to decarbonize critical sectors, the Government approved National Green Hydrogen Mission on Jan 4, 2023 with an initial outlay of Rs 19744 crores upto 2029-30.

The mission will facilitate demand creation, production, utilization, and export of Green Hydrogen and mobilization of Rs 8 lakh crores of investment by 2030.

Likely Outcomes by 2030:
1. Green Hydrogen Production Capacity of at least 5 MMT (Million Metric Tonne) per annum.
2. Reduction in fossil fuel imports by over Rs 1 lakh crores and creation of over 6 lakh jobs.
3. Renewable Energy Capacity Addition of about 125 GW and abatement of nearly 50 MMT of annual GHG emissions.

Interventions:

1. Under the Strategic Interventions of Green Hydrogen Transition (SIGHT) Program, two distinct financial incentive mechanisms – targeting domestic manufacturing of electrolyzers and production of Green Hydrogen – will be provided under the mission.
2. Regions capable of supporting large scale production and/or utilization of hydrogen to be developed as Green Hydrogen Hubs.

Policy Framework:

1. Development of an enabling policy framework to support establishment of Green Hydrogen Ecosystem.

2. Robust Standards and Regulations Framework

3. Public Private Partnership framework for R&D (Strategic Hydrogen Innovation Partnership – SHIP) will also be facilitated under the mission.

4. Skill Development Program

Several Pilot Projects by PSUs like OIL, NTPC etc. have been initiated for the production of Green Hydrogen.

Government Unveils Green Hydrogen Standards 

• It outlines the emission threshold for production of hydrogen that can be classified as ‘green’.
• Well-to-gate emission of not more than 2 kg CO2 for per Kg H2.
  • The well-to-gate emission include water treatment, electrolysis, gas purification, drying and compression of Hydrogen.
  • The scope of the definition encompasses both electrolysis based and biomass based hydrogen production methods.
• A detailed methodology of measurement, reporting, monitoring, on-site verification and certification of green hydrogen and its derivatives will be specified by the Ministry of new and renewable energy.
• Bureau of Energy Efficiency (BEE) under the MoP will be the nodal authority for accreditation of agencies for the monitoring, verification, and certification of green hydrogen production projects.

Significance:

• The definition of green hydrogen brings a lot of clarity to the mission of making India a global green hydrogen hub.

Electrolysers

Electrolysers are a critical technology for the production of low-emission hydrogen from renewable or nuclear electricity.

• Note: Electrolysis is the process of using electricity to split water into hydrogen and oxygen. This reaction takes place in a unit called an Electrolysers.

How does it work?

• Like fuel cells, Electrolysers consist of an anode and a cathode separated by electrolyte. Different
  electrolyzers function in different ways, mainly due to the different type of electrolyte material involved in the iconic species it conducts.
• The cost of electrolyzers and electricity (fuel) make up the largest share of the production cost, and thus developing more efficient electrolyzers will give a major boost to green hydrogen generation in India.

Some Recent Developments:

• IIT Madras develops a cost-effective way to electrolyze sea water to generate hydrogen:
  • Challenges of traditional electrolyzers:
    • Energy Intensive
    • Use of expensive oxide-polymer separator
    • Wastage of fresh water
  • IIT Madras team has addressed all these challenges by developing simple, scalable and cost effective alternatives that are highly efficient in splitting seawater and generating hydrogen.
    • They use alkaline sea water.
    • They use carbon based support material for the electrodes instead of metals to almost eliminate the possibility of corrosion.
    • They have developed a cellulose based separator that is very economic and serves the purpose of allowing hydroxide ions to pass through put prevent oxygen and hydrogen that are generated from crossing over.

Hydrogen- CNG (H-CNG)

• In Sep 2020, MoRT&H has notified hydrogen-enriched compressed natural gas (CNG) as an automobile fuel.
• In Oct 2020, Delhi became the first city in India to operate buses running on hydrogen spiked compressed natural gas (H-CNG) in a six-month pilot project.
  • The buses are running on a new technology patented by Indian Oil Cooperation for producing H-CNG – 18% hydrogen in CNG – directly from natural gas without resorting to conventional blending.
• What is H-CNG?
  • It is an hydrogen enriched compressed natural gas. The ideal hydrogen concentration is 18%.
    • In Delhi, instead of physically blending hydrogen with CNG, hydrogen spiked CNG will be produced using a compact reforming process patented by IOC.
• Advantages of H-CNG over CNG
  • Less Air Pollution
    • Emits 70% less CO;
    • Reduces total hydrocarbons emissions by around 15% and increases fuel efficiency by 3-4%.
  • Increases fuel efficiency
  • Higher power output
• Updates in Sep 2021
  • CNG to HCNG model ‘Capital intensive’; Delhi government unlikely to scale up pilot project.

Way Forward: Following are the essential actions to ensure the launch of hydrogen economy in India

• Promote Demand
  • Identify high demand sectors like green ammonia, oil-refining, heavy duty transport etc. where initial demand can be catalysed via public incentives.
  • Pioneer voluntary purchase mechanisms for green hydrogen embedded products such as green steel or green fertilizers similar to RE100 initiatives, where corporates like Infosys or google pledged to run completely on green energy.
• Reduce cost of production of green hydrogen:
  • Work towards reducing renewable energy tariffs -> 70% of the cost of production of green hydrogen is the cost of renewable energy.
  • Scale: India should strive to incentivise the giga-scale production of green hydrogen components, like electrolysers, to take advantage of the global demand-supply gap and reduce the local green hydrogen prices.
  • India should identify hydrogen production clusters closer to the renewable parks to utilise near-zero cost excess peak power which can be diverted to hydrogen plants
  • Promote R&D: Policymakers must facilitate investments in early-stage piloting and the research and development needed to advance the technology for use in India.
  • Focus on Domestic Manufacturing:
    • Establishing an end-to-end electrolyser manufacturing facility will require more steps than just an PLI scheme. India needs to secure the supply of raw material that are needed for this technology.
  • In the initial phase, Blend Green Hydrogen with Grey Hydrogen (as grey hydrogen is much cheaper to produce)
  • Plan for large scale refuelling network
  • Start on pilot basis for gated infrastructure like airports, ports, warehouses.

Conclusion1

• Scaling up the technology and achieving critical mass remains a big challenge. More vehicles on the road and more supporting infrastructure can lower costs. India’s proposed mission is seen a step in that direction.

Conclusion2:

• Even before it has reached any scale, green hydrogen has been anointed the flag-bearer of India’s low-carbon transition. Hydrogen may be lighter than air, but it will take some heavy lifting to get the ecosystem in place.