THE FUTURE OF MOBILITY – EVS, HYDROGEN AND E-FUEL
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Milton D’Silva examines the pros and cons of mobility of the future with the three available options.
Humans learned to harness fire around 2 million years ago, a pivotal moment in history. The wheel, a later invention, marked progress in the 4th millennium BC. Energy has been central to human activity ever since, becoming a development index. However, excessive energy use has led to a crisis – the generation of greenhouse gases (GHGs). While GHGs are crucial for Earth's temperature, the uncontrolled use of energy has caused global warming. Fossil fuel combustion, responsible for 75% of GHG emissions, is the primary driver of climate change. In 2023, recorded as the hottest year, the world faces risks to life.
Transportation, contributing 28% to GHGs, relies heavily on fossil fuels. Cars, trucks, ships, trains, and aircraft burning fossil fuels contribute to this alarming statistic. Cleaner alternatives are crucial, especially as over 90% of transportation energy sources come from fossils. Energy use, including electricity generation (25% of GHGs), adds to the challenge. With over 60% of electricity from fossil fuels, urgent transformative changes are needed to mitigate environmental consequences.
Given the close relationship between energy and mobility, the world is today engaged in a massive exercise seeking to decarbonise transportation and electricity generation, which holds immense potential to address the burgeoning global climate crisis. By transitioning to cleaner and more sustainable energy sources, such as renewables and alternative fuels, there is significant potential to reduce GHG emissions, making a substantial and positive impact on the fight against climate change. To this end, there has to be a concerted effort with close coordination among policymakers, industries and individuals, to prioritise and invest in initiatives that promote the decarbonisation of these critical sectors to achieve a more sustainable and resilient future.
Alternatives to fossil fuels have always been there and some of the better known and also in use, though not as widely, are bio-diesel, bio-alcohol, bio-gas, chemically stored electricity, hydrogen, non-fossil methane and natural gas, vegetable oil, and in recent years, synthetic fuels or e-fuels.
Decarbonising transportation & energy
The early automobiles were actually battery-powered Electric Vehicles (EVs) and were doing reasonably well before the mass-produced Ford Model T gained immense popularity. The EVs of that era simply could not counter the performance of the IC engine, especially after they got the self-start feature. Thus went the early EV into a long period of hibernation, only to be woken up after the oil shocks of the late 1960s and early 1970s. The EV was further jolted into action by the climate crisis of recent years. The renewed interest in EVs was ignited in part due to the Lunar Roving Vehicle ferried to the moon by the 1971?Apollo 15?mission, and research on the batteries had resulted in better capacities even as the cost remained high. The first serious boost to EVs was provided by the CARB mandate in the US State of California in the 1990s, which specified that automakers sell a small number of lower-emission vehicles, with zero emission being the ultimate goal. In response, several mainstream automobile companies either converted an existing model, or developed a new one with an electric drivetrain. These were at best token attempts and no serious EV barring the General Motors EV1?and Toyota RAV4?EV resulted from it. However, the hybrid Prius launched by Toyota in 1997?attracted global attention and won several awards and accolades, clearing the path for a renewed interest in EVs. An important development during the first decade of the new millennium was the founding of Tesla Motors, a Silicon Valley startup in 2003, as an electric mobility and clean energy company.
In the span of 20?years since, almost all global automakers have at least one EV on offer, if not a portfolio of models to choose from. Global EV sales have risen dramatically, crossing the 10?million mark in 2022. The total EV sales more than tripled in three years, going from 4% in 2020?to 14% in 2022. The momentum further accelerated in 2023?with the total EV sales including plug-in hybrids totalling a whopping 14.2?million, an increase of over 35% over the previous year, which adds to close to 16% of total light vehicle sales globally. The scale of EV adoption is far from uniform and varies from region to country. In general, China leads the EV adoption rate, followed by Europe and the US. In the meanwhile, the decarbonisation of electricity is already happening as close to 30% of global electricity today is produced from renewable sources. The International Renewable Energy Agency (IRENA) estimates that 90?percent of the world’s electricity can and should come from renewable energy by 2050. The best thing about electricity is its ability to integrate renewable sources like hydropower, which is a traditional source of clean energy, and now wind and solar, which are more recent renewable sources.The UN Climate Action Plan lists out five reasons the world should accelerate the pace of decarbonising the energy mix, primarily led by clean electricity.
The other alternative – synthetic fuels or e-fuels – is also relying on hydrogen basically. E-fuels are produced through a process known as the Fischer-Tropsch synthesis, where hydrogen is combined with CO2?extracted from the air and converted into a liquid energy carrier, which is a synthetic hydrocarbon fuel, or e-fuel. The hydrogen used to produce the e-fuel is generated by the electrolysis process that breaks down water into its components of hydrogen and oxygen, and to that extent, it is the same process that produces hydrogen for fuel cell electric vehicles (FCEVs) or other industrial applications. Here it is important to understand that the electricity used to produce hydrogen must be renewable, because using electricity generated from fossil fuels defeats the very purpose of the exercise. The burning of e-fuel in IC engines results in emissions, but the carbon dioxide thus emitted is less that used in producing it, and hence considered carbon neutral, or better still, emitting less CO2?than fossil fuels.
Those who are espousing the cause of e-fuels have formed the eFuel Alliance, an interest group committed to promoting political and social acceptance of e-fuels and to securing their regulatory approval. The alliance represents more than 170?companies, associations and consumer organisations along the e-fuel production value chain.
At this point, one may ask why use hydrogen to produce e-fuels when the same can be used for FCEVs? Or for that matter why use FCEVs when EVs are already popular and serving the purpose well? To understand that, one must study the pros and cons of each of these alternatives – EVs, Hydrogen and E-fuels.
The case for and against EVs Among the three options that form the theme of this article, electric vehicles or EVs are generally considered cleaner than traditional gasoline cars in terms of environmental impact. However, it's important to note that the overall efficiency of an electric vehicle depends on various factors, including how electricity is generated, the manufacturing process, and the lifespan of the vehicle.
While zero tailpipe emissions during operation is the biggest advantage of EVs, the actual environmental impact of the EV depends on the source of the electricity used for charging. The full benefit accrues only if the electricity comes from renewable sources. If the electricity is generated from fossil fuels, some or most of the environmental benefits are lost. Another major point is the environmental footprint of the manufacturing process, which is believed to be less for EVs than fossil fuel cars. But critics point out that the production of batteries for electric vehicles, in particular, involves mining and processing raw materials like lithium, cobalt, and nickel, and this is an area that has not been fully explored for its true impact. Add to that, the cost of battery replacement and the total lifespan cost with recycling.
In summary, while electric vehicles are generally cleaner in terms of direct emissions, the overall environmental impact depends on various factors. Efforts are being made to make both electric vehicles and the electricity grid more sustainable, and advancements in technology and recycling practices are helping address some of the challenges associated with electric vehicle production and end-of-life management.
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Hydrogen and its overall impact on mobility
The comparison between hydrogen fuel cell electric vehicles (FCEVs) and battery-operated electric vehicles (BEVs) involves various factors, and the superiority of one over the other depends on specific circumstances and priorities. In comparison with EVs, FCEVs offer key advantages like a longer range and quick refuelling – it takes only a few minutes to fill a hydrogen tank, whereas charging an electric vehicle can take significantly longer. Hydrogen fuel cells can also be lighter than large battery packs, which can contribute to better efficiency and handling in some cases. Above all, hydrogen fuel cells are highly suitable for hard-to-electrify mobility segments like heavy transportation, aviation and shipping.
However there are also challenges and concerns when it comes to the use of hydrogen, and these are mainly threefold:
What about e-fuels? At the heart of the argument in favour of e-fuels put forward by the eFuel Alliance are four main points:
Against the potential benefits of e-fuels mentioned above, there are some real challenges associated with the production of e-fuels, including the efficiency of the conversion processes and the overall energy losses. The efficiency of converting renewable electricity into synthetic fuels needs improvement for these fuels to be a truly sustainable and scalable solution. Moreover, with the headstart enjoyed by EVs and the rapid scaling of charging infrastructure, it will be interesting to see whether there will be popular demand for e-fuels, if and when there is production with scale.
Summing up
In conclusion, the choice between battery-operated electric vehicles, hydrogen-powered fuel cell vehicles and e-fuels as the third alternative, shall depend on individual preferences, regional infrastructure, and specific use cases. All three technologies have their merits and challenges, and ongoing advancements may continue to shape the landscape of sustainable transportation. Above all, rapid decarbonisation of electricity is essential for the success of these options.
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