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Looking To Better Engines Instead of Electric Vehicles
hlovy writes "Don Runkle thinks it's engines, not batteries, that will make automobiles cleaner and more efficient. 'We unabashedly say that we have the best solution,' says Runkle, the CEO of Allen Park, MI-based engine developer EcoMotors International. The startup, which brought in $23 million in Series B financing this summer from Menlo Park, CA-based Khosla Ventures and Seattle billionaire Bill Gates, has designed an opposing piston, opposing cylinder engine that uses fewer parts than traditional motors do and generates more power from each stroke of the engine, CEO Runkle says. He says the 'opoc' engine is smaller, lighter, and less expensive than the motors already out there, and a more viable option than switching automobile fleets over to electrical power."
If you bothered to RTFA instead of trolling, they explicitly talk about how you can add an electric motor to this engine to really put the mpg off the charts. Basically he's saying that, short term, this will boost the mpg of cars until all electric cars are cheaper / the infrastructure for them is built.
"The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants." ~Thomas Jefferson
There is still room for improvement of the internal combustion engine, one is variable compression.
However - a very limiting factor is that consumers aren't willing to pay for the technology, especially in the US where gasoline is dead cheap compared to many other places in the world.
Just look at technologies that have been created earlier - the Alvar Engine (variable compression with a small piston that rotates phase-adjusted to the camshaft, and is actually a assymetrical counter-piston engine), Smokey Yunick's Hot Vapor engine (heating the fuel beyond boiling point before injection) etc.
Diesel engines are also one of the more fuel efficient engines around at the moment. Efficiency up to 55%.
But what really consumes fuel in many cases is the stop&go traffic in cities. Even a short term accumulation of energy in a capacitor bank would help to keep that down. And vehicle weight is also an important factor. Aerodynamic drag is of course important, but only at highway speeds. In a city you can do fine with a shoe box.
So the future for cars is probably a combination of solutions.
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Tried to figure out how this thing worked and I found this video here: http://www.engineeringtv.com/video/Opposed-Piston-Opposed-Cylinder
Some good technical questions and answers, as well as a working illustrative model of the engine.
The article is light on details, but there's details elsewhere.
The OPOC engine is a horizontally opposed two cylinder two-stroke engine. As a cylinder in a two-stroke engine has a power stroke on every revolution instead of every second revolution, this engine has very high power density compared to a four-stroke engine of the same size.
Traditionally, two-stroke engines have had very poor emissions. Since the exhaust and intake strokes are not separate, the intake mixes with the exhaust to some degree. This means that some of the intake fuel goes out the exhaust unburned, and some of the exhaust remains in the cylinder with the intake charge, reducing peak temperature. This engine, however, uses assisted HCCI with a diesel injection system, meaning the fuel is introduced during compression instead of intake, so unburned intake fuel does not cross over to the exhaust. (I'm not clear what the "assisted" part is in the assisted HCCI. Perhaps there's a spark plug that's only used during low-power, lean burn conditions?)
The cylinder pairs are intended to be balanced and stackable, so that multiples can be connected together for higher output. TFA suggests that it might even be stacked with an electric motor for low-speed operation.
I imagine these would be very useful for a hybrid, despite the summary title. Unassisted HCCI engines have a small power range, but this would be perfectly fine for a series hybrid generator motor running at a fixed RPM for charging.
Like a VW, Subaru, or BMW bike? This is new?
Ok, they may be taking this to a new level, but this design has been around for quite a while.
No. I thought the same and wondered why it was different from a flat 4 layout. This has two pistons per cylinder, each pushing away from each other. It's also an advanced two-stroke. (I remember in the late 80s and early 90s when all the talk was about how two-strokes were going to be the next big thing.)
You need to watch the linked video to see how it works. It's actually kinda cool. Each pair of opposing cylinders can act as an independent unit, so you can shut one unit down when you need less power. The guy claims significant fuel consumption savings.
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The VW Beetle used a horizontally-opposed engine, which is not the same thing as an opposed-piston engine. In an opposed-piston engine, each cylinder is double-ended, with a piston at each end and no head. A horizontally-opposed engine uses ordinary single-ended cylinders with a head and one piston.
No, I don't know anything about this stuff. I just know how to use Google and Wikipedia.
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Supercaps don't come anywhere near the energy density of even chemical batteries. They do have a huge power density and the ability to charge almost instantly though, which is very useful for getting good acceleration out of a small number of cells or for regenerative breaking respectively - so even in a battery car, supercaps can have their place.
"Opposing piston, opposing cylinder" is nothing new and is known for being good for improving balance and reducing vibration. See: Porsche Boxster (Flat-4?), Porsche 911 (I think most if not all 911s have a Flat-6), all Subaru engines (Flat-4 or Flat-6, called "H4 and H6" by Subaru to indicate that they are horizontally opposed engines), and nearly all modern piston aircraft engines.
You're missing half of the picture. The engines you list are all traditional four strokes. This one has an "opposing piston" above each traditional piston, where the valve head should be, moving in opposition to the standard piston (to increase compression, I guess). It's absolutely a different design.
If you go to the site he has a bit more info including a graphic rendering of the engine >> EcoMotors International
As I understand it, "traditional" flat engine, or opposing cylinder engine technology uses multiple crankshafts and cylinders and are often based on two-stroke engine technology. Certainly none of the examples I saw or read about in the wikipedia article (Opposed-Piston Engine) seemed less complex, nor efficient.
This engine, uses two cylinders, each containing two opposing pistons, and only a single crankshaft to obtain 4-stroke emissions benefits without the added complexity of synchronising multiple crankshafts. Also, they're proposing that multiple such powerplants could be daisy-chained together to provide additional power when it is required. In theory, 1-4 of these modules connected thusly could give you performance up to that of an 8cy car, but use as few as two cylinders when the extra horse-power isn't necessary (by "turning on" extra modules as necessary, then turning them back off again when it isn't).
In theory at least, that should radically improve the available efficiencies of modern engines without needing to alter the existing fuel-distribution network, and without a loss of available horsepower when such is required. In that light, I would say it does represent "something new" (as opposed to your assertion to the contrary).
-AC
Nitpick: railroad serial hybrids don't use battery power storage for propulsion. They use a motor-generator fed from a diesel. The diesel is governed at a constant RPM where it has peak efficiency. The motor-gen set acts as a gearbox and clutch -- all electrically controlled. The motors can be installed directly on the bogeys -- you then don't have universal joints to maintain.
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You mean like previously discussed here?
Which was reported here.
It's an electric vehicle with micro-turbines powering the electric generators if the car travels past the 68 mi single charge limit... or if you want the extra boost to do 0 to 60 mph in 3.4 seconds.
Oh, and it should be capable of accepting multi-fuels, so we (in the US) don't have to wait for the lift on extremely high EtOH import tarrifs while we also subsidize our corn -> EtOH program or wait for industrial research to fund (and patent) biochemical oil reactors (i.e. algae to diesel), or any of the other promises which trivialize the three laws of thermodynamics (enthalpy, entropy, and politics).