From: Ken McGlothlen
Date: Tuesday, 14 September, 1999 12:41 PM
Subject: Regarding the Entropy Engine
That's my first reaction to the Entropy Engine, an engine which its inventor
claims runs on no fuel, requires only maintenance, and barring the inevitable
wear and tear could conceivably run forever.
Here's the story, and why I'm deeply skeptical of it interspersed with it.
The Little Engine that Might
by Leander Kahney
Taking on the world's giant energy business, a tiny startup is set to
launch an engine that requires no fuel, produces no pollution, and is
free to run.
This is one of the first disturbing signs. If there really *were* an engine
that required no fuel, produced no pollution, and is free to run, there would
be a huge buzz about it. HUGE. "Oh, it would just get suppressed by the
megaindustrial petroleum complex," you might say, catering to your favorite
conspiracy theory, but lemme tell you, the megaindustrial petroleum complex has
NOTHING on how much the military would love this. You think it's *easy*
carting fuel to tanks, which generally get about a mile per gallon on the flat?
*Gad*, the military would happily *give* me a dozen F-16s for this sort of
technology. So would Greenpeace. So would . . . well, pretty much everybody.
Naturally, the experts think it's too good to be true -- although they
can't exactly say why.
The second disturbing sign. Why not actually put the science up for testing?
Why spend a lot of time theorizing? The second law of thermodynamics tends to
already cover machines like this.
The Entropy engine acts like a heat sponge, absorbing heat in the
atmosphere and converting it to power, Amin said. Since it consumes no
fossil fuels, nuclear fuels, or electrical power, it produces no
emissions, directly or indirectly. Its only byproduct is cold air.
Oh. So it's a heat-differential engine. Nothing new about that. Heat-pump
engines operate via heat-exchange---when you have a heat differential between
one thing and another, that heat energy wants to transfer and create
equilibrium. You can use that transference to drive something. These come in
several forms, but always require a differential in order to work.
Initially, the technology will be used to create an outboard motor for
small pleasure boats, simply because it's the easiest market to break
into, Amin said. But as it is developed, the technology could be used
to run refrigerators, air conditioners, generators -- even automobiles.
Er . . . well, the outboard motor version makes sense, because by immersing
part of the engine in cold water, and leaving part of it in warm air, you're
going to wind up with a heat differential, which can drive a propeller. Of
course, it's not going to be a very powerful engine---the heat differential
isn't that huge---but yeah, it'll drive a small pleasure boat. Slowly.
"There's no reason it can't power a car," Amin said.
I *do* have a problem with this. Where is the heat differential going to come
from? I suppose you could generate a mild one if you had a big metal probe
lodged up your butt---on cold days, your butt would be able to generate enough
power to drive a really teeny car a few miles an hour, and if you could harness
the energy in the buttock-clench efficiently, you might add another mile an
hour at most. But on warm days, while the probe would be a lot more
comfortable, you'd barely be moving at all. And on days where the outside
temperature was in excess of 98.6F, you wouldn't move in the slightest.
So far, Amin has built a prototype, which he said generates one-tenth
of one horsepower. The outboard motor -- yet to be built -- will
produce between two and three horsepower.
I completely scoff. 0.1HP is pretty good for a heat-differential engine; 2HP
requires a much larger differential. You might be able to get that if the prop
were extended down in the water several hundred feet, where the temperature is
near-freezing (depending on the body of water).
It will be roughly the same size as a conventional outboard motor and
only marginally more expensive. But, apart from routine maintenance
and lubrication, the engine will be free to run.
Named after the unit in physics that describes the amount of available
energy in a system, the Entropy engine consists of a central chamber,
filled with air, that has a piston in the center, Amin said.
The engine operates on a cycle. First, a starter motor spins the
engine to a high speed, which pushes the gas to the edge of the central
chamber, as in a centrifuge. As the gas moves to the edge, it creates
a partial vacuum in the center that draws the piston out, compressing
In the second part of the cycle, the engine is slowed, and the gas
redistributes itself throughout the chamber, which increases the
pressure on the piston. Heat trapped in the gas is converted into the
energy that moves the piston, which cools the air in the engine
Curiouser and curiouser. If it runs on no fuel, WHAT DOES THE STARTER MOTOR
REQUIRE? This has to require a very light cylinder to get pushed in and out
with a mild vacuum.
The engine will run year-round in any climate, even in sub-zero
temperatures. Although it operates better in warmer climates, it will
work in any environment above absolute zero (minus 273 degrees
*bzzt* Fatal flaw. It can only work if there's a sufficient heat
differential. And remember, it's not *entirely* fuel-free.
"In physical terms, even ice has a lot of heat," Amin said.
Compared to a Bose-Einstein condensate, yes. But for most practical
Amin claims to have patented the technology in the United States,
Australia, and Europe. He said he has published a book on
thermodynamics and in 1996 received an Engineer of the Year award from
the American Society of Engineers of Indian Origin.
And I've never heard of either the organization, or his book.
Always obsessed with engines, Amin built steam engines as a
teenager. He has devoted more than a decade to the Entropy engine. He
began by looking at gravity as a power source, which eventually led to
the idea of using atmospheric heat.
Lots of kooks devote decades to their dreams. That's not proof one way or the
other that this is a well-thought-out device.
The technology was developed in part when Amin was studying at
Youngstown State University, which helped launch the fledgling company.
Bill Dunn, an associate professor of mechanical engineering at the
University of Illinois at Urbana-Champaign, said that while he hasn't
seen the engine in action, he has examined the materials on Entropy's
Web site. He said the logic appears sound, but the outcome -- free
power -- doesn't make sense.
"It's the end result -- that you can create power from heat at ambient
temperature -- that flies in the face of the basic laws of physics,"
said Dunn, who acknowledges that he hasn't devoted time to figure out
why the engine shouldn't work.
"To track down where his thinking may be flawed is a difficult thing to
do," Dunn said.
In Amin's favor, Dunn noted that he has attracted backing from "some
very intelligent people."
Hedging his bets, Dunn said breakthrough technologies have frequently
been greeted with skepticism. "Every time someone suggests something
like this, you should at least give them the benefit of an open mind."
But not so open that your brain falls out. Many intelligent people have backed
many silly things in the past; that's not exactly a point in favor of the
technology actually working.
Iain MacGill, an energy campaigner at Greenpeace, said that because
vehicle pollution makes up about a third of US greenhouse gas
emissions, a pollution-free engine would be an incredible breakthrough.
Nevertheless, it sounds to him like fiction.
"It's got a flavor of 'too-good-to-be-true' about it," he said. "I'm a
wee bit skeptical."
And I don't blame him one bit.
That's the end of the article. Reviewing www.entropysystems.com doesn't help
much, either. There's a description of the Amin Cycle (the "principle" that
claims that energy can be gotten out of heat, and that the engine generates its
own heat differential over time by cooling down), but it's loaded with fairly
difficult math, and is boiled down to a one-page obfuscated summary. I don't
have the physics skills to bunk or debunk this, but it would be interesting to
subject this to a serious analysis.
For a more detailed synopsis of the Amin Cycle, I had to give up some personal
information. And here we start finding some really questionable things. Amin
mentions Carnot's cycle (the heat-differential engine), and says that by
considering acceleration, he can get better efficiency than Carnot's. In other
words, his engine absorbs heat when it's accelerated and doesn't require a
differential. He then goes into a scenario where two cylinders are spun on a
He correctly points out that this will generate energy as the gas shifts in the
He fails to point out that the centrifuge has to be powered by something.
He correctly points out that energy is conserved according to the first law of
He fails to point out that any physical system leaks temperature differentials
to the outside environment---this is technically conserved energy, since it
hasn't exited the universe, but it's not necessarily conserved within the
What these points do is render most of the rest of the equations useless. By
not considering outside factors to "prove" that the engine works, he ignores
the energy required to get the system going, and ignores the leakage of energy
to the outside.
In short, it doesn't work. Oh, it'll work for the slow outboard motor, but it
won't work for your car. And even given that, it will still require you to
spin up a "starter motor."
The real telling point is in the conclusion, where the last sentence is "Thus
changes in entropy are reversible like any other physical process." This
*does* violate the laws of thermodynamics, thereby lumping the "Amin Cycle" in
with all the other perpetual motion machines that have been invented throughout
the years, wasting the time of everyone involved.
In short, I wouldn't plump down $75K for one of these.