
“Super Engine” may fundamentally change the way internal combustion engines work - Oatseller
http://www.anl.gov/articles/argonne-achates-power-and-delphi-automotive-investigate-new-approach-engines
======
Torkel
I'm assuming the purpose of developing a more efficient engine is to reduce
emissions and thus "saving the planet"? That may seem commendable, but from
what I have read it is actually a wasted effort, unless you can make it 99%+
more efficient (which you cannot). So, even if this engine is all that it
claims (which most other comments here seems to question), it still uses oil
and therefore is part of the problem and not the solution. (Wrote abit about
this a while back with more references: [http://torkeldanielsson.se/reducing-
emissions-is-not-enough](http://torkeldanielsson.se/reducing-emissions-is-not-
enough))

Edited comment: Man, I don't get hacker news... Why do you downvote this? I
thought I was adding a valid and important point - that an increase in
efficiency is fighting the wrong battle. I even added references via link. I
would be super happy if I could be informed of what in this post is offending
or off topic!

~~~
dredmorbius
There are advantages and disadvantages to internal combustion engines.

Compared to _external_ combustion engines (steam engines), ICEs have much
quicker start-up and response times. Steam engines require building up a head
of steam, and actually exhaust the working fluid (water) over time, which is
why steam railroads had water towers every so often.

ICEs have been improved over more than 130 years, and scale from a few CCs of
displacement to many cubic meters -- the smallest ICEs could fit in the palm
of your hand, you could stand in the largest and not reach the sides or top of
the cylinder.

Liquid hydrocarbon fuels are exceptionally energy dense by _both_ weight _and_
volume. This makes certain classes of use very difficult to substitute for:
commercial passenger and freight aircraft, overland truck transport, and
powered marine shipping really have few tractable alternatives. Aircraft would
all but disappear without liquid hydrocarbons (gasoline for piston engines,
kerosene for gas turbines), trucks would probably be replaced with electrified
rail, and shipping would return to wind power. Optimists might suggest nuclear
marine powerplants, but I find that unlikely; ships are lost at far higher
rates than is commonly realised: about 200 every decade, and existing trials
of both military and nonmilitary nuclear marine power have proven it expensive
and nonviable for all but the most demanding instances -- aircraft carriers
and submarines.

They're also quite stable in storage (proved over hundreds of millions of
years), relatively safe to handle (no respiration or exceptional contact
protection required), and their combustion products are _mostly_ benign: CO2
(I'll get to this) and H20 with scant quantities of carbon monoxide, sulfer
and nitrogen oxides, and other contaminants or partial combustion products,
all of which can be greatly mitigated with combustion and exhaust controls and
treatment.

The CO2 exhausted isn't a problem _in itself_ but for the, um, slight problem
that in the past 200 or so years humans have returned to the biosphere carbon
sequestered over several hundreds of millions of years. Which turns out to be
a rather considerable problem.

But it's _only_ a problem where what you're burning are _fossil_ fuels. There
exist several options, though all _much_ more expensive and/or constrained
than present fossil fuels, for creating synthetic hydrocarbon-based liquid
fuels. These _also_ have challenges. Biofuels are intractable at scale given
natural limits on plant production: what's called "HANNP" \-- the human
appropriation of net primary production -- or the photosynthetic ceiling.
There's only so much plant growth which occurs and humans already consume much
of it (40%, biofuel replacement of fossil fuels would consume another 20%, see
Jeffrey S. Duke's "Burning Buried Sunshine" (2003), PDF available online, for
more on this.

Another prospect: sequestering carbon from the biosphere, and combining it
with hydrogen, electrolised from water. The US Navy and national energy labs
(especially Brookhaven), as well as M.I.T., have researched this for the past
50 years. It's proven expensive and hasn't been scaled past very low
production (a few litres), but _does_ work. It raises costs of fuel from one
unit of input energy per 20-40 units made available to _two_ units per _one_
provided -- that's a 40-80x increase in the real cost of fuel.

Not cheap, but it might still be our best option.

~~~
alcubierredrive
For the same reasons you mention, ICEs are also crucial to heavy-duty mobile
robots (see e.g. Boston Dynamics).

~~~
dredmorbius
Seems fuel cells might also fit in there. Though yes, powerplant design (and
noise/exhaust) are limiting factors.

Also: stored-energy locomotion. Fully-powered walking is _expensive_.

~~~
eru
From an energy and CO2 emission point of view, fuel cells are no different
than an internal combustion engine.

~~~
dredmorbius
Fuel cells:

1\. Run silently or near silently. They're generating electricity via redox
reactions, not combusting.

2\. Have effectively no moving parts. Again, no noise or vibration.

3\. Product electricity directly. For powering electronics, this means no
secondary generation required.

4\. Utilise extremely expensive catalysts. The reason you don't see fuel-cell
automobiles (excluding very small numbers of test vehicles) is that the
engines cost, literally, on the order of $1 million, as opposed to a few
hundred for a typical ICE. This price premium has proven difficult to
overcome.

5\. Operate better delivering fairly steady-state power, from what I
understand. A tremendous benefit of ICEs is that they can scale output in a
second or few seconds, with very little throttle lag. Yes, straight-up
electric motors are even better at this, but straight-up batteries tend to not
store much power.

A fuel cell is essentially a battery whose electrolytes you _fill_ rather than
_recharge_ or _replace_. This offers the advantages of fuel-based systems
(high energy capacity) and batteries (direct electrical output).
Unfortunately, it introduces the disadvantages of fuel cells (cost, power
delivery profile).

~~~
eru
I was thinking of hydrocarbon fuel cells (hydrocarbons in, CO2, water, useful
energy and heat out). In any case, I agree with your analysis.

~~~
dredmorbius
Yes, that's one option. I'm a little shakey on the specific function,
characteristics, and reaction materials, but some form of redox and electron
flow is what you're aiming for.

------
kenOfYugen
There is this guy who has made some similar engine prototypes in this field of
efficient opposed piston engines.

PatOP: Single-Crankshaft Opposed-Piston Engine

[http://www.pattakon.com/pattakonPatOP.htm](http://www.pattakon.com/pattakonPatOP.htm)

OPRE: Opposed piston Pulling Rod Engine

[http://www.pattakon.com/pattakonOPRE.htm](http://www.pattakon.com/pattakonOPRE.htm)

    
    
      > A 500cc two stroke can easily make some 80 Nt*m (8 Kp*m) torque.
      > At 6000 rpm this torque makes some 50 KW (70 PS).
      > 50 KW from 20 Kp means 0.4 Kp per KW.
      > And 0.4 Kp/KW with direct injection Diesel efficiency sounds interesting, especially for an engine with such a low cost."

------
elbigbad
So, as I understand it, it combines the compression ignition of diesels with
opposing pistons. The opposing pistons go toward one another and compress the
air/gas mixture and ignite it. The exhaust escapes when the pistons move back
through ports machined in the sides (kind of like a wankel/rotary engine
removes exhaust gasses).

Sounds like they're trading the spark system (a pretty easy to maintain
system) for a second piston/crankshaft/etc. Essentially pulling out a cheap
and perfected system for one that adds a bunch of high stress, expensive
parts. Just from that sounds like a bad idea.

They say the extra efficiency comes from heat loss from the cylinder head, but
I have a hard time believing they're capturing that much extra (double-digits)
efficiency from heat loss alone, especially given the reduced efficiency of
having more moving parts.

~~~
digi_owl
Side ports are also used in 2-stroke piston engines. Most often found on
mopeds and chainsaws.

~~~
taneq
This engine design is, in fact, 2-stroke according to the article.

~~~
digi_owl
It seems to lack a defining characteristic of your typical 2-stroke though,
that the fuel is initially drawn in below the head to lubricate the crankshaft
(this require mixing oil in the gasoline, done automatically on modern
mopeds).

[https://en.wikipedia.org/wiki/Two-
stroke_engine](https://en.wikipedia.org/wiki/Two-stroke_engine)

------
madflame991
"The new engine will meld the best characteristics of gasoline and compression
ignition engines with an innovative piston architecture refined by Achates
Power that sets two pistons moving in opposition in one cylinder."

We already have this technology. Diesel engines ignite the fuel through
compression. We also had the opposing pistons layout for a while
([https://en.wikipedia.org/wiki/Opposed-
piston_engine](https://en.wikipedia.org/wiki/Opposed-piston_engine)).

EDIT: we even have triangular-y shaped opposing engines
([https://en.wikipedia.org/wiki/Napier_Deltic](https://en.wikipedia.org/wiki/Napier_Deltic))

~~~
cicero
This engine appears to burn gasoline rather than diesel fuel. I suspect the
compression must be much higher to ignite gasoline than is required for
diesel.

~~~
dredmorbius
Compression required to "diesel" petrol (gasoline) is _lower_ , which is why
some autos have the problem of continuing to run ("diesel") after the ignition
(and spark) are shut off. Most now incorporate other controls and limiters,
such as controlled fuel injection, to eliminate this.

Gasoline is comprised of a shorter set of hydrocarbons (mostly 6, 8, and 10
chain) than diesel (about 12-16 chain length, though 8-21 carbon are listed at
Wikipedia). Volatility (and ignitability) _increase_ with shorter chains --
methane (C2H6) and butane (C4H10) -- that is, two and four chain hydrocarbons
-- are both gaseous at or near room temperature.

Longer chains still get you heavy fuel oils, tars, etc.

~~~
userbinator
_Longer chains still get you heavy fuel oils, tars, etc._

...and eventually that results in simple plastics like polyethylene, which is
basically a _very_ long chain hydrocarbon:

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

~~~
dredmorbius
Yep. I regret not having studied more chemistry in college. It's only started
coming into context for me recently.

------
userbinator
Efficiency aside, big two-stroke engines, particularly diesels, tend to have a
very distinctive sound. I guess this one, being also two-stroke and
compression ignition, would probably sound somewhat like this:

[https://www.youtube.com/watch?v=mkH9QRaQJM0](https://www.youtube.com/watch?v=mkH9QRaQJM0)

Even if they weren't all that much more efficient, I bet a lot of people who
miss the 2-stroke diesel sound would want one in their car.

~~~
kbart
Modern car engines are already very silent, but many drivers love roaring
sounds (probably due to false logic that more noise == more power). Car makers
know that and fake engine sound using audio system(0) on many cars without
anyone actually noticing, so I don't see why it can't be done in this case
too.

0\. [http://www.huffingtonpost.com/2015/01/23/fake-engine-
sounds-...](http://www.huffingtonpost.com/2015/01/23/fake-engine-sounds-
car_n_6533596.html)

------
vvanders
I thought that gas based engines topped out at 30% due to the heat loss
intrinsic with burning fuel(all that waste heat). Is this tackling that in
some fundamental way or is it just an incremental improvement?

~~~
dredmorbius
Carnot efficiency. 30% is pretty typical in land-based motive systems.
Shipboard combustion engines and coal-fired power plants (of all things) are
rated as high as 45% efficiency.

This is based on input and output temperatures, more than anything.

~~~
vvanders
Got it, so a 1.5x improvement on 30% lines right up with 45%. That's where
they're getting their 50% gains number from.

~~~
dredmorbius
Good eye, though it's not immediately clear that that's strictly edging in on
Carnot efficiencies or if other aspects (two-stroke power cycle, valveless
port-based design, eliminating cylinder-head heat loss -- on which, doesn't
that eventually reach equilibrium temp _anyway_?, etc.) are to credit.

I've seen a few other radical reciprocating energy designs, there are some
interesting YouTube vids I should track down. I think "radial engine" might
reveal something. New Zealand, possibly Australian engineering firm, IIRC.

------
nickhalfasleep
Opposed pistons have had good success in marine and railroad applications.

[https://en.wikipedia.org/wiki/Fairbanks_Morse_38_8-1/8_diese...](https://en.wikipedia.org/wiki/Fairbanks_Morse_38_8-1/8_diesel_engine)

~~~
userbinator
And limited success in trucks:

[https://en.wikipedia.org/wiki/Commer_TS3](https://en.wikipedia.org/wiki/Commer_TS3)

------
epx
Opposed pistons is a way to have a very long stroke engine (high torque and
smaller piston speeds = smoother), without the bigger radius that the
crankshaft pin would have to rotate.

------
brianolson
Large engines (in giant container ships) are supposed to be approaching the
efficiency limit according to theoretical thermodynamics. Does this get small
engines close to the limit?

~~~
JorgeGT
I doubt it very much, since the main difference between the two are thermal
losses due to size and speed.

------
Gravityloss
Achates power has been running engines on test stands since 2011, I haven't
heard of any engines installed anywhere.

Maybe this kind of business is different compared to software where you're
expected to build something revenue generating relatively quickly.

~~~
zardo
That's why VC loves software, no billion dollar factories to build before you
can start selling a product.

~~~
dtap
We have invested in a Company that has Chinese partners building the billion
dollar factories for us.

[http://www.ecomotors.com/post/ecomotors-receives-new-
investm...](http://www.ecomotors.com/post/ecomotors-receives-new-investment-
current-customer-zhongding-power-adding-funding-bill-gates)

------
Houshalter
This is not the same thing as from the article, or even a gas engine, but it
reminds me of this project. I never found out what became of this:
[http://www.nytimes.com/2000/09/19/science/putting-a-
darwinia...](http://www.nytimes.com/2000/09/19/science/putting-a-darwinian-
spin-on-the-diesel-engine.html?pagewanted=all)

>Dr. Senecal's test engine consumed 15 percent less fuel than a standard
engine while producing one-third as much nitric oxide and half the soot.

~~~
Cthulhu_
> I never found out what became of this

That's a common pattern in new (combustion) engine designs; there's a lot of
them being published every year, but almost none of them actually end up being
mass-produced and they dwindle into silence or as just demonstration models.
Why? I don't know; the media only seems to focus on the invention and
potential, not the failure (or if I were to put on my tin foil hat, the
disappearance under mysterious circumstances). The only nonstandard engine
that (AFAIK) ever got some leverage was the rotary wankel engine, and even
that was (iirc) in just one car model.

~~~
semi-extrinsic
Mazda RX7 and RX8 had wankel engines. Nice cars, but higher maintenance than
with normal engines.

I think the main reason for the pattern you observe is that what's optimal and
what's cost effective in a car is highly non-intuitive. Take front-wheel
drive, for instance. Mechanically more complex than RWD, but (apparently)
worth it due to the space savings inside the car.

Or take water-methanol injection: well-understood tech that's been in use
since WW2, can save fuel and reduce NOx emissions significantly, or give
higher power output. But it requires changes to all the fuelling
infrastructure, and that makes it essentially a non-starter outside of racing
cars.

------
Osiris
> The research is being conducted under a three-year project funded by a $9
> million award from DOE's Advanced Research Projects Agency-Energy (ARPA-E)
> and an additional $4 million of cost share from the team members.

So, the total cost of designing this prototype was $13 million? What's the
size of the R&D budget for a typical automaker?

To me this just shows that typically businesses are in the mindset of
"business as usual" because it's what they are comfortable with rather than
looking into radical, new, innovation.

------
KaiserPro
_cough_ I'm going to leave this here....

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

~~~
svachalek
It says in the first paragraph that it's diesel.

~~~
KaiserPro
From the parent article:

 _The new engine will meld the best characteristics of gasoline and
compression ignition engines with an innovative piston architecture refined by
Achates Power that sets two pistons moving in opposition in one cylinder. As
the crowns of the pistons slide toward each other, they compress a mixture of
air and gasoline to such extreme pressures that the mixture auto-ignites
without the need for spark plugs in a process known as compression ignition._

which is the same principle as the deltic engine.

------
nimish
HCCI is difficult enough--high compression ratio requires strengthened
materials. Plus there's the hydrocarbon issues that come up with low temps.
Maybe the heat retained by not having a cylinder head would be able to
compensate? High temp burn/lean burn can lead to high NOx which is pretty bad
if you need a urea injector system.

Mazda, GM and others are known to be working on CI engines for gas targeting
2020, so this might be the next step in 10 years. Assuming we don't all switch
to pure electric...

------
mannykannot
While several people have mentioned the Napier Deltic, there was also the
Junkers Jumo 205 opposed-piston diesel aero engine of the early 1930s.

[http://www.enginehistory.org/Diesels/CH4.pdf](http://www.enginehistory.org/Diesels/CH4.pdf)

Claims of innovative internal combustion engine designs that will be
significantly more efficient than current ones show up every few months. They
never live up to the hype.

------
ck2
Hopefully DOE also has $9 Million or more invested into battery research for
electric motors.

But I guess $9 Million isn't unreasonable if it actually produces engines that
automakers will adopt.

~~~
DrScump
Heck, the Obama administration already blew at least $193 million in the
Fisker debacle.

~~~
ck2
Note the government gives $10 Billion per year in ethanol welfare to
corporations. We could take the loss out of that.

In fact we could fund 50 more startups EACH YEAR with the ethanol subsidy.
Some of them will work, some will fail, still would be same $10 Billion.

------
yoha
For the curious, [1] (via [2]) shows various engine designs.

[1] [https://imgur.com/gallery/bxzeN](https://imgur.com/gallery/bxzeN) [2]
[https://www.reddit.com/r/educationalgifs/comments/468290/a_c...](https://www.reddit.com/r/educationalgifs/comments/468290/a_collection_of_gifs_demonstrating_a_few/)

------
tyingq
Better tech detail here: [http://achatespower.com/our-formula/opposed-
piston/](http://achatespower.com/our-formula/opposed-piston/)

------
digi_owl
Unless its a engine that gets us away from using oil, its not a fundamental
change.

~~~
michaelcampbell
From _burning_ oil, perhaps. Throwing oil into a mythical "Mr. Fusion" and
extracting the mc^2 energy from it that way; yeah, let's do that! =)

------
sologoub
While not an earth-shattering amount, I'd rather see such grants/cost sharing
go to tech that doesn't perpetuate dependence on fossil fuels. In the end,
this tech only means we get to burn less, but not eliminate the emissions all
together.

~~~
sliverstorm
Combustion engines are so fundamental, they go far beyond fossil fuels. They
are one of the best ways of converting chemical energy to work. Fossil fuels
just happen to be very high in chemical energy. You can burn hydrogen,
ethanol, bio-diesel, paraffin, methanol....

IMO the better combustion engines become, the more options for fuel we have.
For example, ethanol compares poorly to gasoline in power & consumption, but
with continued engine development, ethanol will be able to develop as much
power & economy as gasoline does today.

~~~
sologoub
Not familiar with burning paraffin, but of others only hydrogen produces
relatively safe emissions (water vapor), the rest produce the undesirable by
products.

It would be better for smaller applications to move to electric and produce
energy by other means. This requires investment into better batteries/storage
applications. I'd rather all the money go to that instead of combustion
research.

~~~
sliverstorm
Battery-powered 737's eh? While it's a nice dream, electric motors are _way_
behind on power to weight ratio, thanks to batteries. We might get there
someday, but we would need several stacking 10x improvements in battery tech,
and who knows if they exist.

There are still a lot of places where very high power to weight ratio of
combustion engines is extremely important.

~~~
sologoub
How's 737 a small application?

I'm talking cars, bikes and the like...

EDIT: Also, a 737 does not use the type of engine described here, unless you
want them to move back to prop design.

~~~
sliverstorm
_shrug_ Jet engines count as combustion research

But my apologies, I did miss the "small application" part.

~~~
sologoub
Sure, jets burn fuel, so in that they count. However, the article is talking
about a very specific application with opposing pistons and compression-based
ignition. This is similar to how a traditional diesel works.

It's definitely useful to burn less fuel, but still.

