Eaton's fuel saving hydraulic hybrid systems put traditional drivetrains in jeopardy

Eaton, which is better known for its involvement in supercharging muscle cars, has a thing for saving fuel, too. According to a writeup on the outfit's website, it's working up a series hybrid hydraulic system to replace the conventional driveline. The SHH system will wed a high-efficiency diesel engine and a custom hydraulic propulsion system, and by operating at its "sweet spot," it stands to reason that lots of gasoline will be saved as it runs. Better still, the setup involves regenerative breaking in order to recover and reuse energy that's typically wasted, and the engine can safely be shut off when not needed in order to save additional fuel when waiting at a stoplight. So, where is this stuff headed first? UPS trucks, naturally.

[Via Autoblog]

[(Unverified) Posted Dec 27th 2008 6:34AM]

How often is this UPS truck going to be driving at the "sweet spot" to make any difference?

[(Unverified) Posted Dec 27th 2008 7:40AM]

100% of the time.
The "sweet spot" refers to the diesel engine, not the drive train. So when the vehicle needs to move forward, the operator hits the gas pedal, but the computer sees that and says "Ok, I will use some of this stored hydraulic pressure to move the truck." When the hydraulic pressure gets too low, the diesel engine kicks in to get the pressure back up, but it dose so at the diesels sweet spot, which is independent of the speed of the vehicle.

[(Unverified) Posted Dec 27th 2008 7:47AM]

Sweet!

Thanks Paul!

[(Unverified) Posted Dec 27th 2008 8:27AM]

"The Sweet Spot" is having the engine running at the proper RPM to allow it to charge the accumulators. I worked for Eaton, and they are looking at 45-65% fuel savings. It works well on start/stop applications, like a UPS truck or a trash truck. Long hall trucks don't work much, as they don't have time to charge the accumulator. Eaton is also working on a 4 door passanger car getting 89 MPH, but the engine RPM goes from 600 to 6000 to charge, then back to 600. Commmon people might not like the sound of that.

[(Unverified) Posted Dec 27th 2008 8:35AM]

Well, common people would treat other people's deliveries with respect, so UPS shouldn't be too worried about engine acting differently to "normal" vehicles.

[(Unverified) Posted Dec 27th 2008 8:51AM]

Now I am a little confused. Do you gotta get it 6000 RPM before it shifts to the next gear and then drops to 600 RPM?

If that's the case, city driving would seem sort of difficult or you'd just be driving high in 2nd gear for long periods of time. I have a 5-speed Civic Si and i'd be shifting at somewhere around 20mph to get to second and 50mph to get to third gear. By the time I am hitting 6000 RPM, that car is booking. It doesn't seem very safe.

[Arkenklo Posted Dec 27th 2008 5:47PM]

Look, the engine does not do the actual propulsion of the car, it just pumps up pressure in the airtank(s), that is later used to move the car. Imagine the car being a pump-up watergun, where you pump up and store pressure (red light) that is released when needed (green light).

My question is, at 600 rpm, will the engine's pump-pressure (e.g. the air it pumps in to the tanks) match the usage of the car when at full speed? You would not want to run out of air on the middle of a highway!

[Arkenklo Posted Dec 27th 2008 5:48PM]

Correction: 6000 rpm.

[(Unverified) Posted Dec 27th 2008 7:36AM]

Meh, nothing new here, move along.
http://www.popsci.com/cars/article/2002-01/350-horsepower-hydraulic-assisted-hot-looking-tonka-truck

[bstump Posted Dec 27th 2008 9:05AM]

Before you post a link, actually look at the differences that are *obvious* first. Ford's F-350 Tonka is a ** hydraulic assist ** and Eaton's design is ** fully hydraulic ** and that is a big difference. Like the 100 MPG difference in "series" and "parallel" hybrid cars. Until they start making series hybrids (like the Chevrolet Volt... 150 MPG) they won't break 50 or so MPG.

[(Unverified) Posted Dec 28th 2008 3:46PM]

@John: meh -1
@Bob w00t +1

[Rik Posted Dec 27th 2008 7:41AM]

For vehicles which do frequent stops this might indeed be interesting. The overal efficiency of a hydrolic drivetrain is worse than a mechanical one, but having an engine operating at optimum RPM and being able to store engine will outweigh this inefficiency (and also justify the added complexity and weight).

So yes... UPS-, garbage truck, maybe even city busses.

[(Unverified) Posted Dec 28th 2008 12:41AM]

Even if all they used this for was regenerative breaking, the fact that you can do that without Caustic or Expensive batteries is friggin awesome!.

Aside from the pieces that interact with the drive train, the storage tanks are good old highly recyclable steel containers.

[TheLostSwede Posted Dec 27th 2008 7:51AM]

" it stands to reason that lots of gasoline will be saved"

Yeah well, it's a diesel engine, it runs on diesel, not gas, so you'll save loads of gas...

[(Unverified) Posted Dec 27th 2008 10:11AM]

Yes, similar to the Regenerative "breaking" that I guess will fix the truck every time it slows down...

[FordGTGuy Posted Dec 27th 2008 7:58AM]

http://www.newtechspy.com/articles06/hydraulichybrid.html

Ford has been already messing around with this idea.

[wpns Posted Dec 27th 2008 7:59AM]

I'd have to agree that "lots of gasoline will be saved", but shouldn't the amount of DIESEL also be reduced? 8*|

Hybrids are nice, but I'd want to see the tradeoffs between electric, hydraulic, pneumatic, flywheel, etc...

[(Unverified) Posted Dec 27th 2008 8:03AM]

i read about this a few years ago and was very upset it was concept only. i'm very happy this is finally coming to market in some form.
i work with industrial electric over hydraulic equipment all day, and i can speak from experience that hydraulic systems are much more reliable from a shear number of failures sense, as well as cost of repair being much less. so this is a very exciting prospect indeed.

[Ahmed Alzayani Posted Dec 27th 2008 8:08AM]

Is it me or that SHH system look like carotid arteries/veins system with that low/High pressure system and the pump working as heart? naaaa ... it's just me.

[spin cycle Posted Dec 27th 2008 8:24AM]

UPS already drives these around, from another vendor I guess.

Hydraulic drivetrains don't put traditional drivetrains in jeopardy, because hydraulic drivetrains become very inefficient when you want to move rapidly. Ask anyone who has driven a materials handler about it.

[(Unverified) Posted Dec 27th 2008 8:52AM]

nice artcle btw does it work on others? say for example this one

http://www.slime-tube.com/index.php/archives/431

[bullshitexpresscom Posted Dec 27th 2008 8:51AM]

Uhhh Diesels don't run on gasoline.

[ewan Posted Dec 27th 2008 9:45AM]

I nominate "braking" as the most misspelled word of 2008.

[fieldcar Posted Dec 29th 2008 11:56AM]

what about duel/dual?

[kastonie Posted Dec 27th 2008 10:05AM]

I prefer wheel of fortune......

[(Unverified) Posted Dec 27th 2008 10:40AM]

How can hydraulics be used to store energy? As fluids aren't in the main compressible, the amount of energy they can usefully store in compression is low.... are we not talking about a hydraulic-pneumatic system here, people?

[looselycoupled Posted Dec 27th 2008 6:24PM]

I haven't read the details, but I'd assume you are correct..

[(Unverified) Posted Dec 27th 2008 10:43AM]

HEY IS IT ME,
OR ARE THEY USING BATMAN'S "TUMBLER" AS A PROTOTYPE.

[(Unverified) Posted Dec 27th 2008 10:42AM]

Please note: if they keep *breaking* these things they are never going to sell. If you are going to write about cars/trucks please understand the difference between *braking* and *breaking* :-)

[(Unverified) Posted Dec 27th 2008 10:54AM]

Something like this was actually tested several years ago. It used high and low pressure compressed air and was used only for regenerative breaking. It was design mostly for use in public buses as they have to stop a lot. They said something like 60% of the energy was saved from the breaking and stored for acceleration. This saved a lot of wear on the engine and breaks and saved on gas. It was bigger though do to compressed air.

This system though sounds a bit iffy. It requires a lot of load on hydrolic pumps, motors, and lines continuously... not just for breaking. Cooling will likely be an issue. It will likely take a full radiator and fan, not just the little transmission cooler used in automatic transmissions now. Think of the mess you would have when the system develops a leak. I have seen hydrolic line rupture at work.... oh my.

[(Unverified) Posted Dec 27th 2008 12:11PM]

This seems like a great idea to me. Maybe I'm missing something but the hydraulic system seems like it would effectively "buffer" energy between the engine and wheels (including breaking), effectively eliminating much of the inefficiency of that transfer. This seems like it would be good for more than just vehicles making frequent stops. Why isn't this good for all cars. And hydraulics must be more efficient than batteries. Why aren't we building gas/hydraulic hybrids?

[d889 Posted Dec 27th 2008 2:14PM]

mostly because it takes a LOT of psi, something a turbo diesel can easily produce, but those tanks are going to be big and heavy.

[Taylor Yes Taylor Posted Dec 27th 2008 1:53PM]

EXACT idea I had like 8 years ago! I was reading up on hydraulic systems (don't all young children do this?) and it made so much sense! I always knew I should have looked into it, but I never had the time or money till recently, and it hasn't fit it with my other projects lately. :-(
Glad to see someone actually doing it though! If done right the car needs no traditional transmission either! :)
-Taylor

[(Unverified) Posted Dec 27th 2008 2:59PM]

This is a super-old story. The only thing new is that Eaton got involved.

[NameIsDavid Posted Dec 28th 2008 9:42AM]

Even that's not news. The June 2006 press release mentions Eaton:

http://www.pressroom.ups.com/pressreleases/current/0,1088,4694,00.html

[AJerman Posted Dec 27th 2008 2:29PM]

Reading about Eaton makes me miss my Cobra and the scream of the super charger. :(

Still, if this is anything like their superchargers on the Cobras, it'll be a bad ass stock system, and will be easily upgradable for mere pennies, but will still be inefficient compared to aftermarket options, and most people will swap out to a bigger and better system. (This is sarcasm before someone replies telling me how it wont be inefficient or something, other Cobra guys will get it)

[LWRC777 Posted Dec 27th 2008 4:58PM]

Regenerative braking, and hopefully not breaking. Love your content, could you please do a better job editing? I'm not perfect by any means, but the errors I see in blogs of these types are obvious errors that should be easy to fix...

[slack04 Posted Dec 27th 2008 8:07PM]

regenerative breaking sounds counterproductive to me, or is it just engadget's editors?

[(Unverified) Posted Dec 27th 2008 10:29PM]

My dad actually works for EATON and he said that this system is going to work best for stop and go vehicles. So He also guessed UPS is going to be the first to get this tech.

[(Unverified) Posted Dec 30th 2008 4:51PM]

I can see by the expert use of MS paint to draw the diagram that this idea is going far!! I thought that was Engadget's scribble drawing, then I went to the company site, and BAM there it is right on the front page.

Time to close the paint program and call a multimedia consultant guys.