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\title \textbf{THE PROSPECTS OF HYDROGEN AS FUEL SOURCE}\\
	B.Viswanathan\\
	Departmjent of Chemistry.\\
	Indian Institute of Technology Madras, Chennai 600 036\\
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	\section{Abstract}
	in recent times, hydrogen  is considered as alternate fuel source for the depleting fossil fuels. It has been claimed that hydrogen as fuel source has many advantages over fossil fuels, but there are critical factors to be considered before advocating this as a viable fuel source.  The rush into a hydrogen 	economy is neither supported by energy efficiency arguments nor justified with respect to economy or ecology. In fact, it appears, as of now, that hydrogen will not play an important role in 	a sustainable energy economy because the synthetic energy carrier cannot be more 	efficient than the energy from which it is made. There is great anxiety for finding alternate energy source in place of the dwindling (?) fossil fuel sources. This anxiety has contributed to overlook the feasibility of electrons as the primary energy source.Certain myths regarding hydrogen as a fuel source have been raised and they have been refuted too.  In this article, the various aspects of hydrogen as the alternate fuel source is examined from the various points of view, but however, it appears that hydrogen as the fuel source needs more careful consideration and evaluation. \\
	
	Hydrogen fuel for transport application has to wait till the cost of the fuel cell technology becomes comparable to fossil fuels.Also the conversion efficiency of fuel cells  ( to electric power) should be comparable to that of conventional fuel sources.In this sense, hydrogen functions only as energy carrier.\\  

\section{Introduction}

"I believe that water will one day be employed as fuel, that hydrogen and oxygen that constitute it  used singly or together wil furnish an inexhaustible source of heat and light of an intensity of whcih coal is not capable .....water will be the coal of the future  ....Jules Verne, Mysterious Island 1876.\\

It is essential that one assesses the worth of this proposal periodically to see how far the prophetic statement still holds good. In this article, the prospects of hydrogen as the future energy source is considered from the points of view its replacing the fossil fuel sources and also the economics of this fuel in relation to its competitor electric power.\\

Energy conversion is considered as the main component of life on this universe. Almost all activities in this universe are centered around energy conversion and fuel is the main input  ingredient of this process. The selection of fuel was based on the availability and possibly equidistribution,  not much on the energy output so far. There are obvious and claimed advantages in using hydrogen as the fuel source. They are: 
\itemize
\item{Hydrogen can be produced by various methods from natural gas, using nuclear power, employing biomass, and making use of renewable sources like solar and wind.}\\
\item{When consumed in a fuel cell, Hydrogen produces only water. and in this sense it can be considered as a clean fuel}\\
\item{Hydrogen acts as a chemical energy carrier and can be piped or transported.}\\
\item{IHydrogen does not produce greenhouse gas emissions when combusted.}\\
\item{Hydrogen can be used in fuel cells (an electrical device) for electricity generation and heat, as well as for storing renewable energy.} \\

For some time now, we've been hearing that hydrogen is a non-polluting fuel for transport but what are the pros and cons of its production? And why is it being used so little? “It could constitute a breakthrough for the planet as the waste generated by its use to produce energy is water vapour, but today more than 96\% of hydrogen production still derives from non-renewable sources like steam reforming of natural gas, effectively forgoing out its green properties”. [1] \\

Hydrogen is a perfectly clean fuel, because the only waste it produces is water vapour. In its free state it consists of two atoms ($H_2$) which, when combined with oxygen (O) during its use (combustion or, more commonly, in a fuel cell), generate water ($H_2O$). Hydrocarbons, on the other hand, are made up of carbon and hydrogen and, during combustion, when combined with oxygen, produce carbon dioxide ($CO_2$) and other waste that is harmful to the environment and to human health  In addition,  harmful prouctslike nitrogen and sulphur oxides are also evolved when hydrogen is obtained from non-renewable sources like natral gas ).\\

Hydrogen can be obtained by several routes like thermal, thermo-chemical, photo-chemical, photo-electro-chemical, biochemical and so on. Each of these methods have certain limitations and possibilities.  However, among these alternate methods, the electrolysis of water is simple method in which a low voltage current flows through water to form oxygen and hydrogen gas. Hydrogen obtained in this methods is considered as green  because it is obtained through electrolysis of water powered by electricity produced from renewable sources. Grey hydrogen, on the other hand, uses fossil fuel sources, mainly natural gas, which produce greenhouse-gas emissions, thereby undermining its non-zero impact on the environment.\\

The hydrogen combustion engine uses technology which stands out for the absence of any harmful emissions. Its main use, however, is not in the combustion engine but in a fuel cell, developed for space exploration since the 1960s, whereby an electro-chemical process combines hydrogen and oxygen to generate electrical energy, which in turn powers an efficient electric engine.\\

The petrol engine uses only 20/25 \% of the energy introduced and consequently 75/80\% of the fuel is dispersed, producing heat.  These figures are not very exact, but they indicate how inefficient the combustion engine powered by petrol or diesel (fossile fuel) is. \\

In the electric engine, the percentages are entirely reversed. 80\% corresponds to the energy used and only 20\% corresponds to the energy dispersed. However, hydrogen is not immediately and directly exploited within a car engine because it must first be converted into electrical energy to power the engine. “This passage consumes 50\% of the energy and so this 80\% is halved, reducing the amount of energy used to 40\% which is, however, twice as much as that of a petrol engine. With the studies and experiments already under way, it is assumed that this percentage can be significantly improved, while that of the petrol/diesel engine can no longer be further optimized”,\\

“It is anticipated that the cost of green hydrogen can become affordable in the coming years. But the hydrogen engine  remains  more efficient than a conventional petrol/diesel engine. Diesel offers a small financial advantage now over hydrogen, but the enormous environmental benefits would offset the higher cost. One thing is certain: hydrogen is less beneficial for light road transport compared to electric power from renewable sources. The environmental benefits are the same, but the cost of refueling and the availability of a network for charging are better.\\

in spite of all these claims, grey hydrogen is still pollution free. since hydrogen is a gas, its handling gives rise to problems. In addition, the utility of hydrogen has to be evaluated in comparison with electricity and this analysis has shown that the derived hydrogen cannot be more advantages than electricity. [2]\\

Hydrogen energy it is often claimed, offers significant advantages(?) over traditional fuels. In terms of  its clean nature, high energy efficiency, renewable potential, versatility, and capacity to drive technological innovation makes it a promising solution for reducing emissions and transitioning to a green energy future. By embracing hydrogen as a viable fuel source, one can accelerate the shift towards a more sustainable and environmentally friendly energy system. All these are the driving forces for turning to hydrogen as a fuel source but it is necessary that this claim has to be carefully examined and evaluated.\\

\section{Methods of Producing Hydrogen}

As stated, there are various methods available for producing hydrogen. A simplified scheme is shown in Fig.1.
\begin{figure}[h]
	\centering
	\includegraphics[width=0.9\linewidth]{E:/LaTex/chapter/figure/Methods of H2 production.jpg}
	\caption[H2 production]{A simplified scheme for the production of Hydrogen}
	\label{h production}
\end{figure}
\begin{figure}[h]
	\centering
	\includegraphics[width=0.9\linewidth]{E:/LaTex/chapter/figure/H2 production.jpg}
	\caption[H2 production]{An expanded  scheme for the various methods of production of Hydrogen}
	\label{h production}
\end{figure}
For example, there are a number of thermo-chemical cycles proposed and also tested.   Similarly, various biochemical routes have been tested. However, most  of these methods are not cost effective, even the photo-e;ectrp-chemical method whcih was once thought to be an  economic way for water splitting.Electrolytic production of hydrogen has also been under investigation in terms of choice of electrode materials and medium but however the cost effectiveness still eludes.

The following seven myths on  hydrogen economy have been advocated. They are 

\item Hydrogen is too dangerous to ever be used on a large scale\\
\item Hydrogen is a dirty fuel that is part of the problem, not the solution\\
\item Hydrogen is inefficient and not economically viable\\
\item Using hydrogen at scale will require a whole new energy infrastructure\\
\item Tansporting hydrogen over large distances is very expensive\\
\item Transport can be fully electrified, so why do we need hydrogen?\\
\item If hydrogen is so fantastic, we would have started to use it years ago\\


Dharmini Mistry on Oct 1, 2024 have written against some of these myths.   He argues that the statement that hydrogen is unsafe due to its explosive nature,  While hydrogen is highly flammable, so are many other fuels in common use today, like gasoline and natural gas. Advances in technology have made it possible to safely produce, store, and transport hydrogen. Rigorous safety standards and infrastructure, similar to those used for other fuels, are continuously being developed and refined to mitigate risks.\\
  
Ricardo Gorini states  regarding the myth that Hydrogen is Too expensive to Compete with Other Fuels,he argues that Hydrogen production costs are indeed high today, especially for green hydrogen. However, just as the cost of wind and solar power have fallen dramatically over the last 20 years, the cost of hydrogen is expected to fall significantly as technology improves, and economies of scale are realized. Ongoing developments in electrolyzer technology, such as solid oxide and proton exchange membrane (PEM) electrolysers, will help lower costs. Additionally, with increased government and industry collaboration, the hydrogen economy is expected to grow rapidly​\\
 
 regardubg the myth that  Hydrogen is Inefficient Compared to Battery Electric Solutions, his argument While it’s true that hydrogen fuel cells may have lower life `cycle energy efficiency compared to battery electric vehicles (BEVs), they offer distinct advantages in areas where BEVs struggle. These include heavy-duty applications, long-distance travel, and quick refueling. For sectors like long-haul transportation and industrial processes, hydrogen’s advantages make it a more viable solution.\\
 
 Ecen though there are many alternate ways of producing hydrogen from various sources like water, natural gas or biomass. one has to establish the efficiencies of each of these processes clearly not only from the point of view of cast of production but also the impact on environment, and the suitable one has to be established.\\
 
 Hydrogen as the fuel for transport purposes has many challenges and barriers.   Apart from the safety point of view, the fuel cell technology (a device used to convert fuel to electricity) has many barriers to cross. First issue is the conversion efficiency which it is claimed to be high today but still the conversion process has to have its own  efficiency limitation.\\
 
 The main points in favour of hydrogen are:
 Hydrogen is the most abundant element in the universe and it produces almost no pollution when burnt, making it a desirable source of power.\\
 There are many ways to produce hydrogen, which determines whether it is defined as grey, blue, green or pink hydrogen.\\
 As we continue to innovate and improve hydrogen production methods and as the cost of renewable and nuclear energy continues to fall, the role of hydrogen in our energy systems is set to grow.\\
 
 A comparison of hydrogen with other existing fuels is appropriate at this stage.  Such a comparison is assembled in Table 1.\\
 
 Tavke 1 Comparison of Hydrogen with other fuels\\
 
\begin{tabular}{|l|l|l|l|l|}
	\hline
Parameter	& Hydrogen  & Natural   & petrol  & LPG  \\
&& gas&Diesel& \\
	\hline
Calorific Value	& 120=142  & 49-54 & 41-44  & 36-40  \\
MJ/kg &&&&\\
	\hline
Density at STP	& 0.08  & 0.6   & 720  & 510 \\
kg/cu.m &&780 &\\
	\hline
Phase at STP	& gas & gas  & liqid  & liquid  \\
	\hline
Auto ignition temp	& 500-  & 580  & 247-  & 410-  \\
in degrees& 540& &280& 580\\
	\hline
Diffusion coeff	& 0.61  & 0.16  & 0.05 & 0.11  \\
(sq.cm/sec) & & & &\\
	\hline


	
\end{tabular}\\

Let us turn our attention to the methods of producting hydrogen\\

Methods of Producing Hydrogen\\
\item {steam Methane Reforming}\\
\item{Partial oxidation}\\
\item{Auto Thermal Reforming}\\
\item{Methanol Reforming}\\
\item{Pyrolysis, Oxidation and Reduction of Biomass}\\
\item{Electrolyis of water}\\
\item{Fermentation of organic Materials}\\
\item{Thermochemical Splitting of water}\\

Hydrogen will play an increasingly important role in the push toward greater use of renewable energy and the reduction in carbon emissions from the transportation sector, electrical energy generation and transmission, and the production of commodity chemicals, such as ammonia and polyolefins.\\

One should consider the safety related properties of hydrogen in relation to other fuels. This is summarised in Table 2.\\

Table 2. Summary of hydrogen safety related properties compared with other fuels\\


\begin{tabular}{|l|c|c|}
	\hline
Property	& comparsion wih other fuels  & Risjs \\
	\hline
Leak probablility	& Higher than other fuels  & Dangerous  \\
\hline
Volume of fuel released in leak & Higher than other fuels & same as other fuels \\
	\hline
	Energy of fuel released in leak & Lower than other fuels & safe\\
	\hline
	Diffusivity and buoyancy & higher than other fuels & safe\\
	\hline
	Lower flammability in air & Higher than other fuels & same as other fuels\\
	\hline
	Minimum ignition energy & Lower than other fuels & same as other fuels\\
	\hline
	Ignition energy & same as other fuels & same as other fuels\\
	\hline
	Flame velocity & Higher than other fuels & Dangerous\\
	\hline
	Lower detonability  air /fuel ratio & Higher than other fuels & safe\\
	\hline
	Explosive energy per energy stored & Lower thqn other fuels & safe\\
	\hline
	Flame visibility & Lower than other fuels & Dangerous\\
	\hline
	Flame emissivity & Lower than other fuels & safe\\
	\hline
	Flame fumes toxicity & Lower than other fuels & safe\\
	\hline
	Fuel toxicity &Lower than other fuels & safe\\
	\hline
	
\end{tabular}\\


 Table 3. Comparison properties of hydrogen and hydrocarbon fuels.\\

\begin{tabular}{|l|l|l|l|l|l|l|}
	\hline
	Property	& Hydrogen  & Methane  & Propane  & Ethanol  & Methanol  & gasoline  \\
	\hline
	Chemical formula	& H$_{2}$ & CH$_{4}$  & C$_{3}$H$_{8}$&   C$_{2}$H$_{5}$OH & CH$_{3}$OH  & C$_{8}$H$_{18}$  \\
	\hline
Molecular Weight	& 2.02  & 16.04  & 44.1  & 46.07  & 32.04  & 102  \\
	\hline
Molar carbon to hydrogen ratio	& 0.00  & 0.25  & 0.375  & 0.333  & 0.250  & 0.444  \\
	\hline
Stiometric air/fuel ratio mass	& 34.32  & 17.20  & 15.67   & 9.0  & 6.47  & 15.41  \\
	\hline
Latent heat of vapourization 	& 446  & 509  & 449 & 921  & 1176  & 348  \\
(kJ/kg)&&&&&&\\
	\hline
Lower heating value	& 119.91  & 40.02  & 46.40  & 16.86  & 19.93  & 44.50  \\
(MJ/kg)&&&&&&\\
	\hline
Flammability limit	& 4.1-74 & 5.3=15  & 2.2-9.5  & 4.3-19  & 7.3-16  & 1.4-6.7  \\
(\% by volume)&&&&&&\\
	\hline
Self ignition Temp (K)	& 855  & 813  & 755  & 696  & 747  & 530  \\
	\hline
Combustion speed in air(m/s)	& 2.933  & 0.355  & 0.432  & 0.455  & 0.455  & 0.356  \\
	\hline
	Ocatane number& 130+ & 120+ & 104 & 100 & 100 & 86-94\\
	\hline
\end{tabular}\\


There appears to be an anxiety to implement hydrogen as the alternate fuel source.   Though it is expected to be so, one has to consider the following points before implementing such a transition in our energy source.\\

1. Hydrogen production requires energy (electricity or other sources like solar, wind, geothermal) and hence one has to consider the net gain in energy source which can be considerably reduced ultimately.\\

2. The derived fuel source namely hydrogen cannot be better than the primary source which is employed to produce hydrogen.\\

3. The disadvantages of using hydrogen are given in table and it appears that hydrogen as a fuel is in noway better than the conventional fuel sources.\\

4. All alternative fuel options are accompanied by benefits and challenges. Prerequisites for introducing a new fuel include the availability of sufficient production and distribution facilities as well as an adequate bunkering infrastructure. In addition, new fuels in many cases require extensive on-board modifications, which lead to increased complexity and cost\\

5.Environmental impact: If not produced using renewable sources, hydrogen can be polluting.\\

6. High cost: Producing hydrogen can be expensive.\\

7. Storage and transport challenges: Hydrogen is difficult to store and move.\\

8. Infrastructure limitations: There is limited infrastructure for using hydrogen.\\

9. High flammability: Hydrogen can be explosive.\\

In short a comparison of pros and cons of employing hydrogen as fuel source are summarized in Table.4.\\

Table 4.Comparison Table on Pros and Cons of Hydrogen Fuel\\

\begin{tabular}{|l|l|}
	\hline
Pros	& cons  \\
	\hline
Clean power source	& Not free in nature must be extracted \\
	\hline
Abundant and inexhaustible form of energy	& Extraction cost may be high \\
	\hline
No Noise Pollution	& 	Highly flammable in nature \\
	\hline
More efficient than another source of energy	& Regulatory issues must be considered  \\
	\hline
Versatile fuel can be used in various sectors	& Storage and transportation can be an issue  \\
	\hline
Long-range	& Maybe not eco-friendly \\
	\hline
\end{tabular}\\

 Around 15 years ago, pundits were focused on “peak oil” — the idea that the world was running out of oil, or at least inexpensive oil, and that a reckoning was coming. Events of the past decade have proven that theory is wrong. Instead of declining oil production and rising prices, we’ve seen the opposite, nowhere more than here in the United States.  These statements and situation  clearly show that the fear that oil reserves are dwindling is not that true and petroleum technology will be in practice for some time now.\\
 
 Hydrogen is categorized by colour tabs, based on its source. We can divide it into ‘grey’ hydrogen (produced from fossil fuels), ‘blue’ hydrogen (produced from fossil fuels with carbon capture and storage) or ‘green’ hydrogen (produced from renewable electricity).\\
 
 Advantages of Hydrogen fuel:
 
 \item {Readily Available: It is a basic earth element and is available in abundance.}
 \item {Doesn’t Produce Harmful Emissions: When it burns, it doesn’t emit harmful substances. The only by-product or emission from the usage of hydrogen fuel is water. It makes this fuel 100\% clean.}
 \item {Environmentally Friendly: It is a non-toxic substance which is rare for a fuel source.}
\item { Fuel-Efficient: Compared to diesel or gas, it is much more fuel-efficient as it can produce more energy per pound of fuel.}\\
 
 Disadvantages of Hydrogen Fuel:
 
 \item {Expensive: Although it is widely available, it is time-consuming to separate hydrogen gas from its companion substances.}
 \item {Difficult to Store:} 
 \item {Hydrogen is very difficult to store. Its transportation even in a small amount is very expensive.}
\item { Not Easy to Replace Existing Infrastructure: There is not much infrastructure that can support hydrogen as fuel. Also, cars need to be refitted in order to accommodate hydrogen as fuel.]
 \item{Highly Inflammable:   Since it is a very powerful source of fuel, hydrogen can be very flammable. Hydrogen gas burns in air at very wide concentrations – between 4\% and 75\%.}\\
 
 Comparison of technologies for the production of hydrogen is given in Table.5.\\
 
 Table.5.   The cost and other parameters are given\\
 
  \begin{tabular}{|l|l|l|l|l|}
 	\hline
 Proces	& energy required  & Status of  & Efficency(\%)  & cost relative  \\
  & kWh/Nm$^3$ & technology & &to SMR\\
 	\hline
 steam Methane 	& 2.25  & mature  & 70=80  & 1  \\
 reforming(SMR)&&&&\\
 	\hline
 Coal gasification	& 8.6  & Mature  & 60  & 1.4-2.6  \\
 	\hline
 Electrolysis	& 3.54  & Mature  & 27  & 3-10  \\
 	\hline
 Biomass gasification	& - & R and D & 45-50  & 2 - 2.4  \\
 	\hline
 Photoelectrochemical	& - & R and D &-  & - \\
 water splitting & & & &\\
 	\hline
 Photocatalytic	& -  & R and D  & -  & - \\
 	\hline
Photobiological 	& - & R and D  & less than 1  &  \\
 	\hline
 thermochemical cycles	&  & R and D & 35-40  & 6  \\
 	\hline
 \end{tabular}
 
 \section{References}The references are some of the current in literature. They are assembled here to show the thought process of technologiest in pushing this technology.\\
 
1. Alessandro Abbotto, “Idrogeno: tutti i colori dell'energia”, (literally, Hydrogen: all the colours of energy) published in 2021 by Edizioni Dedalo\\

2.M. Aulice Scibioh and B. Viswanathan, Hudrogen Future: Facts and Fallacies, Bulletin of the Catalysis Society of India,3(2004)72-81. \\

3. Maher Al-baghdadi, An Overview of Hydrogen as an Alternative Fuel, Encylopedia, https://www.researchgate.net/publication/342067663, DOI: 10.32545/encyclopedia202006.0003.v1\\

4. 4.Dolf Gielen, Francisco Boshell, Deger Saygin,  Morgan D. Bazilian, Nicholas Wagner, The role of renewable energy in the global energy transformation, Energy Strategy Reviews
Volume 24, April 2019, Pages 38-50. https://doi.org/10.1016/j.esr.2019.01.006\\

5.Phuoc-Anh Le,  Vuong Dinh Trung, Phi Long Nguy, Thi Viet Bac Phung, Jun Natsukicd and Toshiaki Natsuki, The current status of hydrogen energy: an overview, RSC Adv., 2023, 13, 28262.\\

6. M Momirlan  and T.N Veziroglu, Current status of hydrogen energy, Renewable and Sustainable Energy Reviews
Volume 6, Issues 1–2, 2002, Pages 141-179.\\

7. Erfan Abbasian Hamedani, Seyed Ali Alenabi and S. Talebi, Hydrogen as an energy source: A review of production technologies and challenges of fuel cell vehicles, Energy Reports, Volume 12, December 2024, Pages 3778-3794.\\ 

8.Xinrong Yan, Wenguang Zheng, Yajuan Wei and Zhaoqian Yan, Current Status and Economic Analysis of Green Hydrogen Energy Industry Chain, Processes 2024, 12(2), 315; https://doi.org/10.3390/pr12020315\\

9. Bassma Reda, Amr A. Elzamar, Shehab AlFazzani and Shahira M. Ezzat, Green hydrogen as a source of renewable energy: a step towards sustainability, an overview,  Environ Dev Sustain (2024). https://doi.org/10.1007/s10668-024-04892-z\\

10. Thanh Tuan Le, Prabhakar Sharma, Bhaskor Jyoti Bora, 
Viet Dung Tran, Thanh Hai Truong, Huu Cuong Le, 
Phuoc Quy Phong Nguyen, Fueling the future: A comprehensive review of hydrogen energy systems and their challenges, International Journal of Hydrogen Energy
Volume 54, 7 February 2024, Pages 791-816\\

11. Phuoc-Anh, Vuong Dinh Trung, Phi Long Nguyen, Thi Viet Bac Phung, Jun Natsuki  and Toshiaki Natsuki, The current status of hydrogen energy: an overview, DOI: 10.1039/D3RA05158G, RSC Adv., 2023, 13, 28262-28287\\

12.Meiling Yue, Hugo Lambert, Elodie Pahon, Robin Roche, Samir Jemei, and Daniel Hissel, Hydrogen energy systems: A critical review of technologies, applications, trends and challenges, Renewable and Sustainable Energy Reviews
Volume 146, August 2021, 111180\\

13. Peng, S. (2023). Current Status of Hydrogen Energy Development. In: Electrochemical Hydrogen Production from Water Splitting. Springer, Singapore. https://doi.org/10.1007/978-981-99-4468-2_2\\

14.Abdellatif M. Sadeq, Raad Z. Homod, Ahmed Kadhim Hussein, Hussein Togun, Armin Mahmoodi, Haytham F. Isleem, Amit R. Patil, Amin Hedayati Moghaddam and Show mor, Hydrogen energy systems: Technologies, trends, and future prospects, Science of The Total Environment, Volume 939, 20 August 2024, 173622.\\

15. Alka Pareek, Rekha Dom, Jyoti Gupta , Jyothi Chandran , Vivek Adepu and Pramod H. Borse, Insights into renewable hydrogen energy: Recent advances and prospects, Materials Science for Energy Technologies
Volume 3, 2020, Pages 319-327.\\

16. Pobitra Halder, Meisam Babaie, Farhad Salek, Kalpit Shah , Svetlana Stevanovic, Timothy A. Bodisco , Ali Zare, Performance, emissions and economic analyses of hydrogen fuel cell vehicles, Renewable and Sustainable Energy Reviews
Volume 199, July 2024, 114543.\\

17. https://theconversation.com/hydrogen-cars-wont-overtake-electric-vehicles-because-theyre-hampered-by-the-laws-of-science-139899?utm_medium=article_clipboard_share&utm_source=theconversation.com\\  

18.
https://theconversation.com/hydrogen-cars-wont-overtake-electric-vehicles-because-theyre-hampered-by-the-laws-of-science-139899?utm_medium=article_clipboard_share&utm_source=theconversation.com\\

19. https://eartharxiv.org/repository/view/8470/\\






	
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