EPA, Eaton and Partners Developing Full Diesel-Hydraulic Series Hybrid for UPS
10 February 2005
The EPA and its partner, Eaton Corporation–Fluid Power, will build the world’s first full diesel-hydraulic series hybrid delivery truck for UPS. The hybrid system is based on numerous EPA pioneering hybrid patents.
A hybrid hydraulic system uses an accumulator (which stores energy as highly compressed nitrogen gas) and one or more hydraulic pump/motors rather than the battery pack, electric generator/motor and power electronics used in electric hybrids.
Like their electric cousins, hydraulic hybrids can come in different configurations with different benefits.
A milder form of hydraulic hybrid is termed Hydraulic Launch Assist (HLA). With HLA, a reversible hydraulic pump/motor and accumulators are added to optimize fuel economy, while keeping the vehicle’s conventional engine and transmission.
Regenerative braking captures the braking kinetic energy. Earlier EPA prototypes stored and re-delivered about 80% of braking energy back to the wheels. The efficiency of this regenerative braking makes a hybrid hydraulic design very attractive for vehicles operating in stop-and-go conditions.
Benefits of HLA include a 25%–45% improvement in city fuel economy, with a concomitant reduction of emissions by 20%–30%; better acceleration, less brake maintenance and reduced operating costs.
Eaton and Peterbilt announced their joint development of refuse trucks using Eaton’s parallel hydraulic hybrid system—Hydraulic Launch Assist (HLA). Peterbilt plans to build and evaluate a production version of the vehicle this year. (Earlier post).
The diesel-hydraulic hybrid under development for UPS, though, is a full series hybrid system that incorporates the new EPA Clean Diesel Combustion engine (earlier post) for further emissions benefits.
The CDC engine (earlier post) powers a hydraulic pump rather than a generator/motor
- A hydraulic drivetrain replaces the conventional drivetrain and eliminates the need for a transmission.
- Regenerative braking captures additional energy for the hydraulic system
Primary hydraulic components consist of two hydraulic accumulator vessels, one engine hydraulic pump, and one integrated rear-drive hydraulic pump-motor assembly
EPA and Eaton are targeting the following results from the combination of the CDC engine with the hydraulic hybrid system:
60%–70% improvement in fuel economy
Meeting the 2010 heavy-duty NOx standard
Recouping the additional cost of the hydraulic hybrid within 3 years
There are related hydraulic hybrid projects underway with the military.
Resources:
Sounds very promising. I assume that this kind of technology could also be applied to buses and maybe even cars depending on how more or less costly it is compared to the "regular" hybrid technology currently in use.
Posted by: Mikhail Capone | 10 February 2005 at 10:08 PM
The EPA is very pumped (no pun really intended) about it. In theory, it’s less expensive than electric hybrids, both from a components cost...and a weight cost. No big heavy transmission, drivetrain or batteries.
Between the Eaton-Peterbilt project for refuse trucks with HLA, and now the EPA-Eaton-UPS project for the full hybrid, we should get some good operational data to help determine prospects for the future.
Posted by: Mike | 11 February 2005 at 09:16 AM
And since the EPA is a governmental agency, I assume that all the technologies they develop (such as that relatively clean diesel engine you were talking about recently) are in the public domain, or at least available to all car-makers..?
Posted by: Mikhail Capone | 11 February 2005 at 12:02 PM
I believe that’s the case. Inventions and technology developed through public funds—with some obvious exceptions (national security, etc.)—do go into the public domain. (Universities are a big exception to this, since the Bayh-Dole act of 1980.)
Posted by: Mike | 11 February 2005 at 12:57 PM
Not so long ago I saw a French design cocnept for a small car that ran on compressed air. Not a huge winner, and has since faded into obscurity. But if one mates an air compression system to a gas engine... Maybe a viable and cleaner automotive technlogy yet to be fully explored...
Posted by: Lance Funston | 02 March 2005 at 08:18 PM
I should think that the "research" done by the EPA, et al would be available to the public since everything they have done is with public money and hardly their idea...though they would like everyone to think it is. It might be interesting to note that this technology -- in this very form -- was developed in the mid-seventies by an individual (not me!) who tried to get the EPA interested in testing its efficacy, but they were heavily involved with flywheels at the time and thought hydraulics had no promise. Now in 2004 they trot out "their" idea when they could have developed it thirty years ago had they the sense to see the obvious. But at least something has been done...though it was originally accomplished with a few thousands of dollars rather than the probable millions that the EPA has spent.
Posted by: Neil Larkins | 10 April 2005 at 11:03 AM
The lack of political and commercial will to develop more efficient technologies is indeed a sad thing.
With a kind of Apollo project I'm sure that the western world could make great strides in the right direction.
Posted by: Mikhail Capone | 15 April 2005 at 02:30 PM
This hydraulic system is very exciting. I have built a gas electric hybrid and learned a lot in the process. It has its weakness, batteries. where can i get these hydraulic components? This isnt rocket science. any farmboy knows the simplicity of hydraulics. If the epa would release a parts list of parts off the shelf that could be used. This country makes a big mistake by not tapping into the home builder for free research and development.Detroit has looked towards hot rodders for decades for inspiration .turn it loose and stand back. act democratically and create commonwealth. we want parts that work, not products that dont.for the wealth of already rich manufacturers. I want these parts. where are they available???
Posted by: berry nishkian | 13 August 2005 at 10:16 AM
This hydraulic system is very exciting. I have built a gas electric hybrid and learned a lot in the process. It has its weakness, batteries. where can i get these hydraulic components? This isnt rocket science. any farmboy knows the simplicity of hydraulics. If the epa would release a parts list of parts off the shelf that could be used. This country makes a big mistake by not tapping into the home builder for free research and development.Detroit has looked towards hot rodders for decades for inspiration .turn it loose and stand back. act democratically and create commonwealth. we want parts that work, not products that dont.for the wealth of already rich manufacturers. I want these parts. where are they available???
Posted by: berry nishkian | 13 August 2005 at 10:19 AM
You”d have to contact Eaton to find out about availability. Start here.
Posted by: Mike | 13 August 2005 at 10:49 AM
Years ago, students at a technical school, of which the name eludes me now, combined a five horse gas engine with hydraulics, into a volkswagon, and it achieved zero to sixty in eight seconds. Perhaps someone can lend a hand here and remember. It had a high pressure storage tank and such, but that's all I remember. Thing is, it works. I do remember thinking at the time, oh boy, this is bound to get surpressed. I'd love to be in a hydraulic club. How about lets start one guys?
Posted by: Bill | 18 August 2005 at 06:38 PM
That VW was featured in Mother Earth News.
Here is the link
http://www.motherearthnews.com/library/1978_March_April/This_Car_Travels_75_Miles_on_a_Single_Gallon_of_Gasoline_
Posted by: Scott | 22 November 2005 at 10:11 AM
I first came across this concept ( hydrolic hybrid ) in a now out of print magazine during Jimmy Carter's presidentsy. The conversion was done using " off the shelf " Sweedish components. The conversion was done to an AMC vehicle with an inline 6cyl. engine. A standard model was tested against the conversion...the conversion had about 50% better fuel economy. It is past time to do tests on things that have been proved to work...and get on with doing them.
Posted by: A J Nemeth | 25 January 2006 at 12:17 PM
Currently there are no components that you can purchase to make a valid hydraulic hybrid. I attended the October HTUF meeting and drove both the EPA’s hydraulic hybrid and a FMTV with Eaton’s series hydraulic hybrid. Neither of these vehicles have valid systems to gain much fuel economy with out driver training. The biggest hurdle with any regenerative system is to capture the braking energy. Most people brake hard enough that the braking energy is 2 to 4 times the acceleration energy. This means the in the pumping mode a 14,400 lbs parcel deliver truck must handle about 600 hp input to capture all the braking energy available. This also requires all wheels have pump/motors attached or skidding will happen when empty.
Posted by: Ed Danzer | 25 February 2006 at 11:01 AM
That kind of funny the first one built that i have seen. Was built as a vw conversion at the university of phoenix by a physics class in the early 1970's.The major probblem this class had was after the conversion the vw motor was much to large.They replaced it with a 20 hp. koch deisel.
Braking was hadled by a switch and vaulve atached in tandum with the conventional braking system and when engajed reverced flow from motor to pump the vaulve allowed control of how much flued was pumped back into the acumulater and how much went though a bypass cuircit. If more braking was required depessing the brakepeddle farther ingajed convinsional braking in the normal maner.
the point of filling in a few of the gaps in the earlyer references two the mother earth new artical is this consept in valid for electric or pneumatic hybrids as well,and farmboy is right is not rocket science
Posted by: clay mccormick | 16 May 2006 at 12:48 AM
Here is an interesting article in car hydraulics. Maybe it helps.
http://www.zercustoms.com/news/Car-Hydraulics-1.php
Posted by: Hydro Newbie | 21 August 2006 at 06:57 AM
Here is an interesting article in car hydraulics. Maybe it helps.
http://www.zercustoms.com/news/Car-Hydraulics-1.php
Posted by: Car Hydraulics | 21 August 2006 at 06:58 AM
Has anyone seen one of these vehicles today? This article is over two and a half years old.
Posted by: Allan F | 01 October 2007 at 10:49 AM
Allan-
UPS ran one of these vehicles for about a month on a real delivery route with a real UPS driver with no support last fall (06) to gather data. The partners (EPA, Eaton, etc) are gearing up for a run of about 50 preproduction vehicles. You have to remember, the design for a single truck is different than for mass produced vehicles, and the parts are not "off the shelf" as people claim, and it takes time to develop manufacturing plans. Eaton and Peterbilt are currently making parallel hybrid versions for garbage trucks.
Posted by: | 07 December 2007 at 07:19 AM
This site needs a "mark as spam" or "remove spam" link in it. The identical posts by "Hydro Newbie" and "Car Hydraulics" have nothing to do with hydraulic hybrid propulsion. They link to an article about hydraulic suspension components for lowriders and other b.s.
Posted by: DaChesserCat | 05 September 2009 at 08:31 AM
"If something is screwed up somebody somewhere wants it that way"
A passenger car that gets 100 miles per gallon of biodiesel is very possible. Carbon ultra capacitors, this nitrogen device, light weight materials and design, Two cylinder horizontal engines that make 200 horse power all are here now.
Question is: How much gasoline do you get to sell? And how much tax do you get to collect?
As long as there is even one drop of oil and one poof natural gas left to sell there will never be a 100 mpg car...
Posted by: JOBLESSINUSA | 01 October 2010 at 11:44 AM