
New two-stroke engine design could help keep internal combustion around longer - clouddrover
https://www.roadandtrack.com/new-cars/car-technology/a32612802/entry-ignition-two-stroke-engine-design-explained/
======
leoedin
Even with the increased electrification of transport, there's still a very
strong case for liquid fuel - it just offers an energy density so much higher
than batteries, especially in off-grid or remote situations.

Electric drivetrains open up an interesting potential for range-extenders
which charge the batteries. The constraints are different than conventional
engines - lower peak power, more-or-less continuous power output operation, no
sudden torque changes. Different constraints generally mean a different
optimal solution.

~~~
henearkr
There is not a huge gap at all.

Li-metal batteries [edit: still an immature tech] are at around 14 MJ / kg,
and gasoline is at 47.5 MJ / kg.

Moreover, suppose that you are _really_ "off-grid". Meaning, you are off any
fuel supply network!! In this case precisely, you would be saved by electric-
related techs, such as photovoltaic.

~~~
lizknope
I have driven through parts of the western US where it is 100 miles to the
next gas/petrol station. There are farms and ranches in these areas but they
are connected to the electrical grid with wires. It seems like having an
electric tractor and charging at the farm would be more convenient than
transporting hundreds of gallons of diesel fuel from 100 miles away.

~~~
Vvector
Tractors are bursty. They are heavily used at planting and harvesting. Farmers
can't spend long periods of time recharging in the middle of planting season.
And it would be too expensive to buy 12 hours of battery capacity for a couple
times a year.

Gas still wins with a short refuel time.

~~~
supportlocal4h
Actually, batteries win on refuel time. Swapping batteries is much faster than
filling a tank. Gas wins on meantime between refuels and in other categories.
Farmers can and happily will spend super long periods of time recharging if
they can operate during the recharge.

My own initial experiences have been mixed. Overall advantage still goes to
gas. But I think we're very close to getting this battery thing figured out.
Just a few years away. When we look back it will seem like it happened
overnight.

~~~
gambiting
>>Actually, batteries win on refuel time. Swapping batteries is much faster
than filling a tank

By that logic, you could say that there is absolutely no difference, because
if you can imagine a car where the battery can be swapped, you should be able
to imagine a car where the entire fuel tank is swapped. A tractor arrives at a
station, and instead of filling up 500 litres of diesel, the entire tank is
simply replaced with a full one. It wins again since fuel tanks are cheap -
they are just metal and plastic after all, you can have several just sitting
there, full or empty.

The fact that no one has done it yet suggests that this really isn't an issue
- commercial diesel filling stations usually run at much higher pressure than
your regular pumps, a truck/tractor tank fills in minutes because of a much
higher flow rate.

~~~
bananabreakfast
That is very silly and disingenuous argument to make and a total straw man.

Swapping gas tanks provides no advantage and you conveniently ignore the whole
point of the batteries which is that you don't need any fuel infrastructure to
fill your tanks!

~~~
Vvector
> you don't need any fuel infrastructure to fill your tanks!

A fuel infrastructure costs magnitudes less than just one battery pack. You
just need a large tank and pump.

------
avhon1
All of the skeptical comments I've read here are talking about how ICE are
already obsolete, since electric cars are cleaner, quieter, and simpler. I'm
picturing this engine being used in other applications (even though the
website, and the journal the engine is publushed in, are automotive).

Stationary generators and marine drivetrains come to mind. Those are less
sensitive to the greater size and weight that this engine might have, and they
benefit greatly from the ability to load fuel, store it, burn it as needed,
and be refueled at any time, even while running.

As an example, my local university's datacenter has two rooms full of
batteries for power backup. They instantly switch on, but can only power the
datacenter for a short time. To protect against extended blackouts, there are
two redundant diesel generators in the sub-basement, and enough fuel to run
the datacenter for several months. Battery technology seems to have a ways to
go before it'll be worthwhile to just have a basement full of batteries as
long-term backup power.

People with those sorts of use cases are probably going to be relying on ICEs
for a long time to come. In the meanwhile, efficiency improvements can make
them less harmful to own and operate. And even after 150 years of developing
ICEs, engineers are still coming up with ideas, maybe even practical ones, to
gain those improvements.

~~~
cameldrv
Flow batteries are a possible solution. Energy density is substantially less
though, so they may not be practical for applications where the battery is
only rarely used.

~~~
barbegal
Whats the advantage of a flow battery over a fuel cell which has higher energy
density?

~~~
cameldrv
I think that the main thing is that in general the "fuel" for a flow battery
can be stored at ambient temperature and pressure, and so the tankage is
cheaper.

In their basic function though I agree they are very similar.

------
opwieurposiu
Right before jet engines took over the military aviation market, you saw some
very complex, high efficiency piston engines. Mechanical marvels they were,
only now are automotive engines catching up in performance. Ultimately they
were all commercial failures, the jet engine had a lot more headroom for
improvement and was mechanically much simpler.

[https://en.wikipedia.org/wiki/Napier_Nomad](https://en.wikipedia.org/wiki/Napier_Nomad)

~~~
throwaway894345
I've noticed a very general principle here. Things which are 'before their
time' obviously tend to fail, but the interesting bit IMO is that 'before
their time' often means "the problem isn't yet constrained such that the
efficiencies afforded by the design are economically significant". I think
this explains why so much software (my branch of engineering) is miserably
inefficient and bug-ridden despite the fact that we have technology to improve
efficiency and quality by several orders of magnitude (at a relatively modest
cost)--the economic context simply doesn't place a very high value on
efficiency and quality, presumably because the market is comparing software
against the many, many orders of magnitude worse performance afforded by
humans.

Perhaps all of this is obvious to many others; it's interesting and novel to
me, anyway.

------
mangecoeur
History is littered with the corpses of 'better' IC engine designs... the
basic problem is you need to retool your entire factory and re-design your
vehicles. If you are doing that today, why not just jump straight to electric
motors?

~~~
JoeAltmaier
Because battery efficiency is still only 10% of liquid fuel efficiency, in
kwh/kg.

~~~
travisporter
This is correct, but this is density not efficiency.

~~~
JoeAltmaier
For transportation that's the pivotal interesting measure. Efficiency is for
grids etc. For moving energy around, the weight is critical.

~~~
travisporter
I agree the weight is critical but kWh/kg is still not efficiency. Efficiency
= "power discharged by"/"power delivered to" battery

~~~
JoeAltmaier
Yes thanks everybody knows what efficiency is. It factors into transportation,
only in the effect it has on fuel weight. Essentially, on how it effects
kWh(delivered)/kg.

------
londons_explore
Investment into productionizing these kind of advances has pretty much
stopped.

It's a bit like hard drives... As soon as the SSD arrived, everyone saw that
hard drives would eventually die out, so manufacturers pretty much stopped new
technology development. Sure, there have been a few small advances, but seek
times and data read speeds haven't gone up for a decade, and capacities have
only crept up.

IC engines are the same. It might take them 30 years to die out, but in those
30 years there won't be any significant tech advances, because every company
that makes them is only optimizing for cost in a shrinking market.

~~~
AmVess
That's not even remotely true. Increasing emissions standards and economy
standards means that ICE development continues apace. Nissan, for instance,
recently put into production a variable compression engine, and all
manufacturers are pairing ICE advances with electric for even larger gains.

Honda has a nicely sized sedan that gets 55 MPG city out of a drivetrain unit
that is amply powerful.

Most of them produce small 4-cylinder engines that are as powerful as the
V-6's that proceeded them, all while producing less emissions and offering
greater fuel economy. Even Ford, Chevy, and RAM are putting gas 4-cylinder
engines in their mid-size trucks are just as capable at 8-cylinder engines
used to be just not very long ago.

Emissions and fuel economy standards will continue to tighten, which means
that ICE development will continue for a long time.

~~~
londons_explore
Most of those improvements are not really new technology, but instead
technology from European cars (where gas taxes are high) just imported into
the USA (where previously people didn't care about MPG much because gas is
much cheaper).

~~~
AmVess
It is a global effort, and not one limited to the US. Besides, the biggest
improvements in ICE fuel economy and power are from Japan, not Europe. Europe
hitched its wagon to the diesel engine, and we all know how that turned out.

Sure, turbochargers and hybrid tech aren't new in an of themselves, but that
doesn't matter because there's still a lot of room for development left in
them.

Even just 5 years ago, the idea of getting a roomy, nicely configured sedan
that gets 55MPG city was a silly notion. Now, Honda sells them all day for
$24k USD.

~~~
NullPrefix
>Even just 5 years ago, the idea of getting a roomy, nicely configured sedan
that gets 55MPG city was a silly notion

VW diesels from the 90s were doing 5 or 6 l/100km

~~~
AmVess
Those were neither roomy nor nicely configured.

------
imdoor
The theoretical efficiency gain appears to be greater than the stated 14%. The
article cites a video [1] which in turn cites 49% vs 63% maximum theoretical
thermal efficiency for a traditional engine and for the Entry Ignition engine,
respectively. That makes it a 14 percentage point increase which is 29%
increase in efficiency.

[1]
[https://www.youtube.com/watch?v=oiUnqlGzLw8](https://www.youtube.com/watch?v=oiUnqlGzLw8)

~~~
ksec
Thank You I had the exact same question in mind. ~30% increase is a lot.

I wonder how much more efficiency can we continue to squeeze out from ICE?

------
geekuillaume
Link to the video:
[https://www.youtube.com/watch?v=oiUnqlGzLw8](https://www.youtube.com/watch?v=oiUnqlGzLw8)

------
mrfusion
I just watched the video. Can anyone answer these questions?

What prevents the burning from getting into the mixing chamber? It seems like
the sliding valve is open while it’s burning. And there’s higher pressure in
the cylinder.

What prevents the mixing chamber gas from getting into the compression
reservoir?

~~~
MontagFTB
I can’t answer the second question, but as to the first my understanding from
the video is that the ignition cylinder starts out as much lower pressure that
the fuel/air chamber, and as the slide valves open the mixture naturally moves
from high to low pressure. The heat contained within the cylinder starts the
ignition of the mixture upon entry (hence the name of the engine).

I don’t understand how the heat differential between the injection and
ignition phases is so great that ignition happens as the slide valve opens,
but so little that ignition doesn’t happen within the fuel injection chamber.
Perhaps the pressure differential regulates that as well?

------
trhway
It is basically a split cycle engine and the "New" is a bit overblown by more
than 100 years. Even similar non-spark based hot ignition was used back then:

[https://en.wikipedia.org/wiki/Split_cycle_engine](https://en.wikipedia.org/wiki/Split_cycle_engine)

"The Backus Water Motor Company of Newark, New Jersey was producing an early
example of a split cycle engine as far back as 1891. The engine, of "a
modified A form, with the crank-shaft at the top", was water-cooled and
consisted of one working cylinder and one compressing cylinder of equal size
and utilized a hot-tube ignitor system."

~~~
throwaway0a5e
"Fuel injection has been tried for 50yr, there's no way it will be
commercially successful now"

-some guy in 1980.

History is littered with inventions that didn't gain widespread use initially
then some little advancement(s) came along that make the inventions workable
when revisited and tweaked. Repeating firearms and electric lightbulbs are two
good examples.

I don't pretend to know which bucket this "new" engine advancement will fit
into but I think your judgement is premature.

~~~
jacquesm
Bosch fuel injection was commercialized in 1967.

~~~
throwaway0a5e
You're not wrong but to imply that Boch fuel injection was successful would be
to wear some really rose colored glasses. Boch fuel injection was such a small
improvement over contemporary cabruerators and such a downgrade in terms of
maintenance and cost of ownership that it was more or less universally reviled
by everyone who was not into technology for technology's sake. It never really
achieved widespread use. If you wanted a glass half full perspective you could
say it gave 1st generation throttle body based injector systems a low bar to
exceed. Bosch mechanical fuel injection is almost a perfect example of an
implementation of a technology not ready for mass market adoption that later
became ready for mass market with the advent of new technology (cheap digital
electronics in this case).

~~~
jacquesm
Volvo, Citroen and many others besides extensively adopted the Bosch fuel
injection system and those cars performed better and were more fuel efficient
than their equivalents without. Quite a few of them still run today, the big
difference in price is what held back faster adoption more than anything else.

I've worked on those systems, they were clearly a game changer, incremental
improvements got us to where we are today. Almost no single technology hits
the ground running, especially not in inherently conservative domains such as
automotive. Interesting implementation details made the Citroen one much
harder to work on.

Electronics aren't perfect either, they make it a lot harder to keep such
older vehicles functioning whereas the purely mechanical ones from an earlier
era will quite likely last practically for ever.

Note that Diesel has had mechanical fuel injection for much, much longer and
that it wasn't exactly new technology to begin with. It's just that the
conditions in a gasoline engine are a bit different which needed a re-thinking
of the concept.

The jetronic is now 50 years old:

[https://www.bosch.com/stories/50-years-of-bosch-gasoline-
inj...](https://www.bosch.com/stories/50-years-of-bosch-gasoline-injection-
jetronic/)

To suggest that fuel injection had to wait until the 80's before it was
commercialized is a ridiculous attempt to rewrite history.

------
rbanffy
Well... If we cut too much carbon emissions it's a relief we can count on such
engines to fill in the void. ;-)

------
thrower123
I am relatively certain that people will be rebuilding old Detroit and Cummins
diesel engines in heavy equipment for at least the next 50 years, if not 100.

I have been surprised at how much 40V/80V electric systems are cutting into
what was traditionally two-stroke light engines for string trimmers and
mowers. The batteries are expensive though, and I don't know how many you'd
need to have in rotation to be able to keep one fully charged and ready to go
under continuous usage.

~~~
mikestew
For the weed trimmer and lawn mower I purchased at U. S. chain Lowes, the
magic number of batteries is 3. The mower came with 2, and the trimmer with 1.
The charger can charge a battery _almost_ as fast as the mower can consume
them, so the third is needed for a little slack. You could get by with only
two if you're content to get a beverage between batteries.

Theoretically, anyway; with our tiny yard this is seldom tested. Which why I'm
annoyed by neighbors that buy a new gas-powered mower. There is not a yard
within at least a 3 mile radius of me that can't be mowed by a modern,
lithium-battery push mower.

------
hinkley
A 2-stroke engine has one ignition per revolution per cylinder. A 4 stroke
engine has half an ignition per revolution per cylinder (or two revolutions
per ignition).

This engine has only one combustion chamber for every four cylinders, which
means that it experiences one quarter of an ignition per revolution per
cylinder.

It's not a 4-stroke, clearly, but I don't see how you can get away with
calling it a 2-stroke either. The strokes kind of become beside the point, but
if I had to I might want to call this an 8-stroke engine.

I see them pilfering ideas from this for 'simpler' engines. That valve design
feels like it could be used for about anything. I've seen other engine designs
that use a single intake chamber, so that part has in fact already been done
before.

That recuperation chamber trick I think could be applied to a traditional
4-stroke engine, which you would need every other cycle and therefore could
share with another cylinder (opposed by a full revolution, which I hear at
least a few 4 cylinders do). And something similar could be applied on the
intake side (although you might have to use the ignition cylinder for the
second compression) and then fully half of your cylinders fire.

------
russellbeattie
I'm not sure which is worse, YouTube videos where all they do is summarize a
written news article, or a written news article summarizing a YouTube video...

~~~
avhon1
I'm pleased with a YouTube video that visually, verbally, and efficiently
explains the contents of a paper that costs $33 to read.

------
Jemm
All this debate of electric vs internal combustion when the article is about a
theoretical design that has yet to be proven.

~~~
ReactiveJelly
Only Consumer Reports can tell us which car is better: One with batteries that
don't exist, or one with a gas engine that doesn't exist

------
safgasCVS
Between this, camless motors, motors that can switch between different
combustion cycles and variable compression ratios there is technically still a
lot of improvement to be had. Whether or not the political climate will allow
those improvements to come forth is unfortunately uncertain

~~~
clarry
I think it's less a matter of political climate and more just that these
improvements are "too little, too late" when electrics are already taking over
markets.

How long would I need to wait for these theoretical improvements to go from
lab to reliable, mass market cars? Why aren't they here already, why would I
wait a decade or two (for what, a 10%-20% improvement?) if I can buy a full
electric car tomorrow?

I don't object to improvements, but it's a race, and it seems like ICEs are
losing that race unless they can do something impressive on a very short
timescale.

~~~
safgasCVS
ICE motors have been evolving for over a century now so the improvements will
become ever smaller. Despite that slowdown in progress, the energy density
advantage of fuel over batteries still vast. Regulation should, in my opinion,
be be aggressively pushing towards reducing vehicle size and weight instead of
focusing on the fuel. Having a 2 ton car to move a 60kg person from stop light
to stop light is just insane

~~~
_ph_
_Having a 2 ton car to move a 60kg person from stop light to stop light is
just insane_

That is solely determined by the energy required. And there is, where the
electric car excels. A Tesla uses less than the equivalent of 2l of fuel for
100km or in other units achieves 120mpg. In situations you describe, it fares
even better, as 60% of the kinetic energy built up is gained back when braking
using the electric motors. So mass is much less a problem with electric cars
than with combustion engines, which can't recuperate the kinetic energy.

~~~
avhon1
Electrics are great for low-speed stop-and-go. They're not as good on a
highway, though. 0% of the energy spent displacing air at 70mph is recovered.

~~~
_ph_
They are still better than any car with a combustion engine at highway speeds.
They don't recuperate while driving at constant speed of course, but still
they have the greater efficiency of the electric motor vs. the combustion
engine. Usually they have better aerodynamics too. But the weight doesn't play
a role there, only making the cars physically smaller - less air resistance -
would improve the energy consumption at highway speeds.

------
01100011
Would a 14% increase in thermal efficiency translate into a meaningful
reduction in carbon emitted per mile driven? This is interesting technology,
but I'm not sure it will prolong the internal combustion engine, at least as
far as mass market consumer transportation is concerned.

~~~
m_mueller
I'm thinking this might have interesting applications as a range extender of
EVs, like e.g. available for the BMW i30. A vehicle with 150-200km electric
range and an optional extender could be quite compelling for lots of usecases.

~~~
1bc29b36f623ba8
Yes, hybrids are definitely a viable use-case. There are also other
applications where a combustion engine makes much more sense, especially if
this design can be used for smaller engines like chainsaw engines and
lawnmower engines.

The article doesn't mention what kind of fuel this new engine uses, but if it
can run on ethanol, or synthesized hydrocarbons like E-diesel then this could
definitely be a good thing.

~~~
henearkr
Chainsaws and lawnmowers _do_ _need_ to go electric now.

They are the ones that ought to go electric first. The easier ones.

~~~
henearkr
> Thankfully electricity is not available everywhere, e.g. in the middle of a
> forest.

Well, do you easily find a refueling station in the middle of the forest? If
you brought spare fuel containers, why wouldn't you bring all-the-same spare
batteries?

~~~
m_mueller
Energy density is probably quite important for something handheld like a
chainsaw. I doubt batteries are able to replace that except for some light
garden use.

~~~
g8oz
40 volt electric chainsaws are fine for anything under 6 inches in diameter.
That covers almost all household use cases as well as many trail thinning
situations.

~~~
1bc29b36f623ba8
Yeah, the current offerings just won't cut it for professional use though,
which I suspect account for much of chainsaw emissions.

------
mcv
> _" Of course, it's not like we're going to be seeing entry ignition engines
> popping up in road cars any time soon. The method is unproven, and carries a
> bunch of unknowns regarding cooling, balancing, and reliability. Still, it's
> a sign not all is lost in the world of fuel-powered engines."_

Electric cars are well on their way to proving themselves. This new technology
is too late to slow down the electric takeover. Its only use is to make those
vehicles that are unable to switch to electric (probably because of fuel
density or a need for rapid refueling) cleaner. Which is still useful, I
guess. Though I'm hoping they won't be necessary at all.

------
hinkley
I recall years ago when someone had rediscovered sleeve valves and was going
to apply them to small displacement 4 cycles in order to get the weight down
to be more competitive with 2 cycle engines.

It wasn't clear that the article author was aware of them either (and in fact
I don't think I'd heard of them until the movie Sahara)

------
taylodl
Jason Fenske's _Engineering Explained_ is an excellent YT channel. I
especially enjoy his physics for gearheads.

------
rurban
So a multi-chamber diesel. Why should more chambers be more efficient than the
single chamber diesel engine? Because per revolution you get double self-
ignitions, at the cost of more room and more gas moving around. Hmm, not bad.
Bad reminds me on the Wankel. Only better in theory.

~~~
arh68
I'm not sure this [1] is what you're talking about but it reminded me of
reading about pre-combustion chambers in diesel cylinders. Interesting stuff.

[1]
[https://en.wikipedia.org/wiki/Indirect_injection#Classificat...](https://en.wikipedia.org/wiki/Indirect_injection#Classification_of_indirect_combustion_chambers)

~~~
rurban
Not really interesting. That's from the pre-BOSCH direct injection area.
Modern diesel engines are far more efficient than that.

------
chrismartin
It looks like the slider valve is surrounded on all sides by hot air-fuel
mixture and combustion gas. Will the fingers of the slider valve need to be
lubricated? Might they be lubricated without consuming (burning) excessive oil
(with consequent increase of emissions)?

------
tyho
Boring. Even an IC engine operating at the Carnot limit would still emit
carbon. Convert every IC on earth to a one with theoretically perfect
efficiency and we still blast past 1.5deg warming in a few decades.

~~~
ReticentVole
Plus the cognitive impacts of higher CO2, plus ocean acidification, plus the
noise and pollution being exhausted at ground level inside cities, plus
supporting barbaric regimes that mine the oil.

Just scrap it all and go full electric. Coming out of COVID lockdown is a
great time to invest and mandate.

------
liammonahan
Isn’t this much like how Diesel engines work? They compress air first to heat
it to the point that when mixed with fuel it spontaneously ignites. Maybe glow
plugs can make a comeback.

~~~
fnordfnordfnord
It sounds somewhat similar to a supercharged two-stroke design like the
formerly very popular Detroit Diesels (8V71, 6V92TA, for example). None of
those engines were very efficient though.

Also, glow plugs are only used for starting.

------
mrfusion
So how does this efficiency compare to gas turbines? Should gas power plants
switch to this if it pans out? Or it might be good for portable generators.

Does two stroke mean it won’t need oil changes?

~~~
rootusrootus
> Does two stroke mean it won’t need oil changes?

This is not the same kind of two-stroke engine. The one you're thinking of
pumps the fuel air mixture through the crankcase, which is why it cannot use
the same oiling system that a typical four-stroke engine does. The oil would
be diluted with fuel pretty quickly, and also carried into the combustion
chamber and burned off. So adding the oil to the fuel is how you get around
that, but then you're constantly burning oil.

------
aww_dang
How would the ignition piston be preheated from a cold start?

~~~
kwhitefoot
Glowplug?

------
otagekki
Is this patented?

------
sanatgersappa
How dare you!

------
holstvoogd
Clutching at straws to make dead dinosaurs go boom!

~~~
chrisseaton
Oil isn’t from dinosaurs that’s a myth.

[https://www.thoughtco.com/does-oil-come-from-
dinosaurs-10920...](https://www.thoughtco.com/does-oil-come-from-
dinosaurs-1092003)

------
henearkr
\- Hi, I've found an improved NP primality test algorithm!!

\- Uh, but, years ago, a P algorithm has been found...

\- Yes, but if you want to stay in NP, I have a better one!!

This is the way I feel...

We have a 0 emission motor -- electric engine--

and people telling us that, if ever we would not like to use 0 emission, then
they have a better IC engine...

~~~
avhon1
ICEs have a lot of life left in them yet. Hydrocarbon fuels are energy-dense
and easily transported, stored, and transferred. It will be a long time before
every use case can be practically and economically covered by electric motors.

~~~
henearkr
Electrons are energy-dense and easily transported, stored, and transferred.
That's probably what a lot of people have missed about the technological
revolution that just happened.

> ICEs have a lot of life left in them yet.

> [...]

> It will be a long time before every use case can be practically and
> economically covered by electric motors.

Let the near-future prove you wrong on both statements ;)

The maximum density of Li-metal batteries [edit: still an immature tech] is
around 14 MJ / kg, whereas gasoline is the highest energy-density fossil fuel
at 47.5 MJ / kg. This is not a huge gap at all.

~~~
jabl
Wikipedia says energy density of Li ion batteries is around 0.5 MJ/kg, which
is about 100 times less than hydrocarbon fuels.

And no, electricity isn't easily stored nor transmitted compared to
hydrocarbons. Electricity, of course, does have a number of major advantages
which is why we use it.

~~~
henearkr
Yes electricity is more easily transmitted than fuel. Compare: pipeline vs
electric line.

And no I'm not speaking of Li-ion. Sorry but I was speaking about Li-metal, a
still immature technology.

So that weakens my argument. On the other hand, that shows that the path to
improvement is huge, and could why not surprise us by becoming better density
than fuel.

~~~
jabl
> Yes electricity is more easily transmitted than fuel. Compare: pipeline vs
> electric line.

Lets do that. High voltage electricity transmission has losses about 4% per
1000 km (HVDC somewhat less, but is a point-to-point system so less flexible
than the common AC transmission). By comparison the pumping power required for
transporting liquid hydrocarbons is less than 1/10th of that. Also, a high
voltage transmission line is an eyesore requiring about 50m wide right of way,
whereas a pipeline of equivalent capacity needs a much narrower corridor.

I'm not saying we shouldn't go for electricity, but we need to be frank about
the upsides and downsides. (Most experts seem to agree that in order to
decarbonize our societies the basic recipe is to 1) Clean up electricity
generation. 2) Electrify everything.)

I used Li-ion for the battery comparison, since that is the best rechargeable
battery technology that actually exists. I'm highly skeptical that a new
battery technology with two orders of magnitude better energy density is
possible. It's very hard to get anywhere close to the energy density stored in
the chemical bonds in fuels. Or, well, yes we do know of fuels with better
energy density than chemical fuels, namely nuclear fuels.

~~~
henearkr
I could be wrong, but seems like a pipeline is extremely hard to build, with
lots of volume of material, concrete or steel. It seems lighter and easier to
build an HV electric line. I see HV lines everywhere, but very few pipelines.

Also, pipeline operations (leakage etc) seem a PITA.

That was my idea behind thinking electricity is easier.

However, the sheer ratio {transport energy} / {transported energy} is indeed
in favor of pipeline, as you mentionned.

\--

I found that you can bury HV lines: [https://retasite.wordpress.com/burying-
high-voltage-lines/](https://retasite.wordpress.com/burying-high-voltage-
lines/)

I found that it costs between $2.9 million and $13 million per mile to build a
new pipeline, whereas it costs $285,000 per mile for a HV line and $1.5
million per mile if you build it underground.

------
Dumblydorr
Our climate doesn't care if the engine is 14% more efficient. That is still
vastly too much carbon emission for people or goods to move from A to B.
Consider every time any ICE engine moves anything, those emissions will warm
the planet for millennia. We can not afford to use these destructive engines,
even though fossil fuel interests make them slightly less damaging.

We must have a sustainable transport system, which ultimately means using non-
fossil derived fuel. That means way way better batteries, fuel cells, or other
up and coming solutions. Any iteration on ICE is just kicking the can down the
road.

------
thecleaner
Why is this not a welcome change even considering the supply chain
difficulties ? The thing is combustion engine fumes make up for a tiny
fraction of carbon emissions. The major part is from industrial production
(like cement factories, steel plants etc.) In fact, electric vehicles will
only help if the electricity powering it was generated from renewable sources
which is a significant fraction in certain countries but not most. Considering
these facts I guess good combustion is still a welcome change.

~~~
technicaldonut
>In fact, electric vehicles will only help if the electricity powering it was
generated from renewable sources which is a significant fraction in certain
countries but not most.

That statement is false. If an EV is run on electricity generated from coal
only, the overall emissions output is close to that of a comparable ICE car
[0]. Introduce some friendlier methods into the mix and your beating ICE by
quite a margin.

The main source of emissions from an EV come from the manufacturing process.
Even those can be significantly reduced when proper methods are applied.

[0] [https://www.forbes.com/sites/jamesellsmoor/2019/05/20/are-
el...](https://www.forbes.com/sites/jamesellsmoor/2019/05/20/are-electric-
vehicles-really-better-for-the-environment/#48b8b99776d2)

