h₂ – The Future of Automotive Fuel

Underpinned by a global shift towards decarbonization, hydrogen is gaining significance as an energy vector, especially for high-emission sectors that do not use electricity directly. Our research (Capgemini Research Institute Report – Low-Carbon Hydrogen: A Path to a Greener Future) suggests that a majority (64%) of E&U organizations are planning to invest in low-carbon hydrogen (or green hydrogen) initiatives by 2030; and 9 in 10 plan to do so by 2050.

On average, 0.4% of total annual revenue is earmarked for low-carbon hydrogen by E&U organizations. Investments are flowing in across the hydrogen value chain – especially into the development of cost-effective production technology (52% of organizations investing), electrolyzers and, fuel cells (45%), and hydrogen infrastructure (53%) to help create alternative revenue streams and aid in decarbonization efforts.

For hydrogen production to be considered low-carbon, it must come under the EU’s proposed emissions threshold of 3.38 kg CO₂ -equivalent per kg of hydrogen 5, which is 70% lower than that of the predefined fossil fuel comparator, including transport and other nonproduction emissions.

Hydrogen adoption in the automotive industry

There is a raging discussion about hydrogen adoption in the automotive industry today. Questions start with the very generation of hydrogen (source of generation, cost of generation, energy density, transportation) to issues relating to energy transformation (electric to potential (hydrogen) to electric (FCV), loss during these conversions, etc.)

The current cost of hydrogen generation is USD0.5–USD8/kg (depending on the process) and primary sources of generation include coal (black), crude (blue), and electrolysis (green). Today, most production is the B2 (square) type, which is derived either from carbon or crude.

Currently, this type of hydrogen is generally used as a reducing agent in industrial manufacturing. Demand is limited and therefore production and associated costs remain high. Moreover, CO2 emissions per kg of hydrogen are very high and while this could probably be justified in cases calling for the specialized use of hydrogen, the story changes when it is looked at as fuel.

Coal is burned to generate methane and from there, hydrogen is generated. Alternatively, it can be the product of the fractional distillation of crude. In either case, consuming fuel to generate another fuel does little to solve the problem of CO₂ emissions. Generating emissions to create an emission-free fuel that will have no emissions defeats the entire purpose of an alternate fuel.

Thus, as an automotive fuel, only green hydrogen can be useful in reducing emissions and achieving carbon neutrality. However, this green hydrogen must be generated using electricity from alternate/renewable sources (solar, wind, hydro, biomass).

If we want hydrogen to be a viable fuel in the automobile industry, we need to ensure uninterrupted availability and extensive distribution capabilities.

But let’s first revisit the concept of energy transformation (transmutation) in an automobile. An automobile carries energy as potential energy. It moves when potential energy is transformed by combustion (gasoline/natural gas in ICE) or magnetic induction (electric charge stored in EV batteries), into kinetic energy. Thus, a good fuel carries more potential energy per kg of its weight. Let’s see where hydrogen stands in this aspect.

There are four cost-input points and emission-generation points. To make hydrogen cost-effective and usable as fuel while achieving emission neutrality, we need to analyze inputs and outputs at these four stages.

As discussed earlier, B2 (squared) type hydrogen is not viable from either a cost or an emission perspective. Truly green hydrogen, however, is another matter.

Green hydrogen is generated from hydrolysis, which requires two important components: water and electricity

• Water – There is no need to use fresh water. Recycled water, methane-rich water (sewage, industrial waste), or even seawater can be used, serving the dual purpose of procuring hydrogen and reusing water. Moreover, if seawater is used, numerous mineral bi-products are created (Na, K, etc.).

• Electricity – The idea of using electricity generated from fossil fuels (coal, gas) to create green hydrogen is pointless. Only renewable electricity (solar, wind, hydro, biomass – this one is very relevant for agrarian societies such as India, East Asia, Africa, Latin America, parts of the US, and Australia) should be used. This will increase the well-being of farmers by increasing their income while enabling the extraction of every last bit of energy from agricultural produce, thereby reducing the carbon footprint and achieving full circularity – sustainability.

For green electricity, large solar farms can be established in coastal or desert locations with high solar radiation zones and wind farms can be constructed in hilly areas. Apart from the desert, anywhere there is sun and wind, there will also be water.  Therefore, to generate green hydrogen you would just have to establish hydrolysers.  

The green hydrogen produced can be transported through pipelines and distributed just like LNG. Farmers have biomass, water, and solar panels to generate electricity; they use electricity to generate H₂ by electrolysis; they compress it in compressors that run on green electricity; and supply H₂ for transportation.

Having established that H₂ is a better fuel due to its high heating value and discussed how green hydrogen can be generated, the next question is what technology should be used to convert this hydrogen back into kinetic energy to drive automotive.

What will be the cost of such technologies and where will they be effective – i.e., the cost-benefit conundrum? Given hydrogen’s better fuel capability, it would be more effective in commercial transportation, which utilizes heavy equipment such as HCV, trains, heavy earth movers, ships etc. In this context, it would be generally safe to consider hydrogen as a replacement for diesel/CNG engines.

There are two technologies to do this:

1. Fuel cell: A fuel cell acts like an engine that converts H₂ into electricity and that electricity drives the electric motor to achieve locomotion. Fuel cell technology uses polymer and platinum, making it expensive, however, research into developing ceramic membranes is currently underway.
2. Hydrogen ICE: Internal combustion engines would be used to burn H₂ instead of gasoline or CNG and produce water vapour and NO₂ as emissions. Such engines are easy to modify and easy to operate because distribution networks are already in place in various geographies, such as India.

In conclusion, I am certain that H₂ is not far away in areas spread up to 15⁰ on either side of the equator, where green hydrogen can easily be harnessed due to favourable climatic conditions and fuel cell technology can be used to drive automotive due to prevailing economic conditions.