Fuel cell vehicles - Revision history

Johnno: /* Hydrogen interests are fossil fuel interests */

2023-03-02T23:46:17Z

Hydrogen interests are fossil fuel interests

Johnno: Add images from Commons

2021-09-14T00:04:22Z

Add images from Commons

Johnno: /* Hydrogen interests are fossil fuel interests */

2021-07-12T22:23:11Z

Hydrogen interests are fossil fuel interests

Johnno: /* Hydrogen interests are fossil fuel interests */

2021-06-24T23:54:59Z

Hydrogen interests are fossil fuel interests

Johnno: /* Hydrogen as a fuel */

2021-06-24T23:54:09Z

Hydrogen as a fuel

Johnno: /* So what is a fuel cell? */

2021-05-17T02:45:46Z

So what is a fuel cell?

Johnno at 00:42, 17 May 2021

2021-05-17T00:42:07Z

Johnno at 00:40, 17 May 2021

2021-05-17T00:40:22Z

Johnno: Move some stuff to footnotes.

2021-05-17T00:37:18Z

Move some stuff to footnotes.

Johnno at 00:20, 17 May 2021

2021-05-17T00:20:02Z

@@ Line 59: / Line 59: @@
 Hydrogen is being researched and hyped by the fossil fuel industry, desperate to re-purpose their
 colossal global infrastructure assets, which are about to be ruinously stranded over the coming
-decade by the highly disruptive combination of exponential growth in solar photovoltaics, electric
+decades by the highly disruptive combination of exponential growth in solar photovoltaics, electric
 vehicles, battery technology advances, and ongoing global fossil fuel divestment.

@@ Line 7: / Line 7: @@
 === So what is a fuel cell? ===
+[[File:Toyota Mirai fuel cell badge SAO 2016 9043.jpg|thumb]]
 A fuel cell creates an electric current from the catalysed reaction of a fuel (say, hydrogen gas, H₂) and an oxidant, often oxygen
 (O₂) from air. First demonstrated in the early nineteenth century, modern fuel cells are based on the
@@ Line 65: / Line 65: @@
 === Power density ===
+[[File:Hyundai NEXO Hydrogen Fuel Cell Car beim Autosalon Genf 2018 i.jpg|thumb|Hydrogen fuel tank in a Hyundai Nexo]]
 Hydrogen is the lightest element, so while its energy-to-mass ratio is impressive, its very low
 density works against it. To store hydrogen at the sorts of high power-to-volume efficiencies that
@@ Line 150: / Line 150: @@
 == Is there still a case for Hydrogen? ==
+[[File:First London bus ESQ64993 (ex LK53 MBV), 2003 Mercedez-Benz Citaro fuel cell, London Transport Museum Acton depot, 7 August 2011 (5).jpg|thumb]]
 Yes.

@@ Line 46: / Line 46: @@
 First and most significantly of all, water electrolysis is expensive because it requires huge
 amounts of electricity. Consequently, ''over 95% of the world's hydrogen is produced from fossil fuels''.
-Specifically, from the steam reformation of natural gas, which is approximately:
+Specifically, from the steam reformation of natural gas (methane), which is approximately:
 : CH₄ + H₂O → 3H₂ + CO
@@ Line 55: / Line 55: @@
 This means of course that currently, powering your car with hydrogen is effectively powering it with
 natural gas, but in a much less efficient and far more expensive manner than if you had just powered
-it with CNG.
+it with methane directly.
 Hydrogen is being researched and hyped by the fossil fuel industry, desperate to re-purpose their

@@ Line 45: / Line 45: @@
 First and most significantly of all, water electrolysis is expensive because it requires huge
-amounts of electricity. Consequently, ''over 95% of the world's hydrogen is produced from fossil
+amounts of electricity. Consequently, ''over 95% of the world's hydrogen is produced from fossil fuels''.
-fuels''. Specifically, from the steam reformation of natural gas, which is approximately:
+Specifically, from the steam reformation of natural gas, which is approximately:
 : CH₄ + H₂O → 3H₂ + CO

@@ Line 41: / Line 41: @@
 and when combusted produces the same amount of water it was derived from. There are however a lot of
 problems to overcome for it to be a sensible option for powering private transportation.
 === Power density ===
@@ Line 47: / Line 69: @@
 density works against it. To store hydrogen at the sorts of high power-to-volume efficiencies that
 we are used to with liquid hydrocarbon fuels, we need to compress it in tanks capable of extremely
-high pressure (70 MPa), or as a cryogenic liquid kept at -252°C, which is achievable only with space
+high pressure, or as a cryogenic liquid kept at -252°C, which is practical only with space
 programme budgets.
 For example, travelling 600 km in a modern FCEV requires only 4-5 kg of H₂ gas to power the fuel
 cell, but to store this seemingly modest amount of fuel on-board requires an 80 litre tank
-pressurised to 70,000 kPa, three times higher than a typical CNG tank.
+pressurised to 70 MPa, three times higher than a typical CNG tank.
 === Safety ===
@@ Line 60: / Line 82: @@
 collisions is not available.
-With a detonation velocity at standard pressure of about 3-4 km/s, hydrogen is explosive and thus
+With a detonation velocity at standard pressure of about 3-4 km/s, hydrogen is highly explosive and
-much more dangerous in failure situations than petrol, given that at the point of any detonation, it
+thus much more dangerous in failure situations than petrol, given that at the point of any
-will already be a rapidly decompressing gas mixing with air across a large expanding surface area.<ref name="note-3">In
+detonation it will already be a rapidly decompressing gas mixing with air across a large expanding
-short, car go boom, very bad.</ref>
+surface area.<ref name="note-3">In short, such bad, very boom, wow.</ref>
 The safest and most power-dense way to store hydrogen remains bonding it to carbon; hydrocarbons
@@ Line 85: / Line 107: @@
 : 3H₂ + O₃ → 3H₂O
-This is an irreversible (non-equilibrium) reaction. It also never gets mentioned anywhere, and seems to only be known to meteorologists.
+This is an irreversible (non-equilibrium) reaction. It also never gets mentioned anywhere, and seems to
 only be known to meteorologists.
 == Overall efficiency ==

@@ Line 8: / Line 8: @@
 === So what is a fuel cell? ===
-A fuel cell creates an electric current from the catalysed reaction of a fuel and oxidant, usually
+A fuel cell creates an electric current from the catalysed reaction of a fuel (say, hydrogen gas, H₂) and an oxidant, often oxygen
-O₂ from air. First demonstrated in the early nineteenth century, modern fuel cells are based on the
+(O₂) from air. First demonstrated in the early nineteenth century, modern fuel cells are based on the
 hydrogen-powered alkaline or "Bacon" fuel cells invented in the 1930s by English engineer Francis
 Bacon.<ref name="note-2">Not Francis Bacon (1561–1626), the English philosopher and Lord Chancellor.</ref>

@@ Line 125: / Line 125: @@
 Meanwhile the full unit of electricity is transmitted to your garage at about 5% transmission loss and stored in your battery EV with about 85% efficiency; there is some loss from charger equipment AC/DC conversion and as heat.
-After fuel transportation and fueling/charging the vehicle:
+After fuel transportation and fueling/charging the vehicle:<ref name="note-distributed-h2-gen">The hydrogen fuel transportation step could be eliminated if fuel filling stations had sufficient installed solar PV and a piped water supply; eliminating this step results in a slightly higher 35% final efficiency. This would however massively increase the cost of building the currently non-existent infrastructure of hydrogen filling stations, and move the complex industrial production and processing of hydrogen gas into built-up and residential areas.</ref>
 * FCEV: ''e'' = 56%
@@ Line 140: / Line 140: @@
 It is a sad fact that in 2020 most of the world's electricity is still generated by burning fossil fuels and emitting CO₂. Using this electricity to refine water into hydrogen, just to power a fuel cell powered electric vehicle at a dismal 31% efficiency is not really helping, when you could just replace the hydrogen tank and fuel cell with a big battery and go more than twice the distance.
 === Comparison with petrol-powered cars ===

← Older revision		Revision as of 00:40, 17 May 2021
Line 174:		Line 174:
	== Notes ==		== Notes ==

−	~~{{reflist}}~~	+	<references/>

@@ Line 3: / Line 3: @@
 A ''fuel cell electric vehicle'' (FCEV) is an ''electric vehicle'' (EV)—that is, a vehicle propelled
 using only electric motors—powered by the electricity generated by passing fuel and oxidant through
-a ''fuel cell''. In practice they usually have an additional small battery for storing extra charge
+a ''fuel cell''.<ref name="note-1">In practice, they usually have an additional small battery for storing extra charge
-from regenerative braking, which can also be used to power the motors to improve range.
+from regenerative braking, which can also be used to power the motors, to improve range.</ref>
 === So what is a fuel cell? ===
@@ Line 11: / Line 11: @@
 O₂ from air. First demonstrated in the early nineteenth century, modern fuel cells are based on the
 hydrogen-powered alkaline or "Bacon" fuel cells invented in the 1930s by English engineer Francis
-Bacon.
+Bacon.<ref name="note-2">Not Francis Bacon (1561–1626), the English philosopher and Lord Chancellor.</ref>
 Most fuel cells produce low voltages, typically less than one volt, so they are usually
@@ Line 62: / Line 62: @@
 With a detonation velocity at standard pressure of about 3-4 km/s, hydrogen is explosive and thus
 much more dangerous in failure situations than petrol, given that at the point of any detonation, it
-will already be a rapidly decompressing gas mixing with air across a large expanding surface area. In
+will already be a rapidly decompressing gas mixing with air across a large expanding surface area.<ref name="note-3">In
-short, car go boom, very bad.
+short, car go boom, very bad.</ref>
 The safest and most power-dense way to store hydrogen remains bonding it to carbon; hydrocarbons
@@ Line 148: / Line 148: @@
 Many pundits think we are truly witnessing a revolution in transport not seen since the disappearance of steam traction engines and horses a hundred years ago; it's just that nobody in 2020 has noticed yet, the same way nobody noticed the internet in 1995.
 == Glossary ==
@@ Line 165: / Line 171: @@
 * Ball, P., June 2003. [https://www.nature.com/news/2003/030609/full/news030609-14.html "Hydrogen fuel could widen ozone hole"], Nature News. DOI: [https://dx.doi.org/10.1038/news030609-14 10.1038/news030609-14]<!--<ref name="nature-2003-ozone">{{Cite web |last=Ball |first=Philip |title=Hydrogen fuel could widen ozone hole |work=Nature News |date=13 June 2003 |url= https://www.nature.com/news/2003/030609/full/news030609-14.html |access-date=17 May 2021 |doi=10.1038/news030609-14 }}</ref>-->
 * Bossel, Ulf, October 2006. [https://doi.org/10.1109/JPROC.2006.883715 "Does a Hydrogen Economy Make Sense?"] Proceedings of the IEEE '''94''':10.

@@ Line 163: / Line 163: @@
 * [https://www.nzhydrogen.org/nz-hydrogen-projects "Current Hydrogen projects in New Zealand"], Hydrogen New Zealand Association
 * Moyle, M. P., et al., March 1960. [https://dx.doi.org/10.1002/aic.690060118 "Detonation Characteristics of Hydrogen-Oxygen Mixtures"], AIChE Journal, American Institute of Chemical Engineers.
 * Bossel, Ulf, October 2006. [https://doi.org/10.1109/JPROC.2006.883715 "Does a Hydrogen Economy Make Sense?"] Proceedings of the IEEE '''94''':10.