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Getting serious about diesel hybrids
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I am surprised we are not seeing or at least hearing more about diesel/hybrid intentions.
In my own life gasoline is all but retired for anything other than recreational use. I doubt I would ever consider buying a gasoline hybrid. A diesel hybrid is another story.
In my own life gasoline is all but retired for anything other than recreational use. I doubt I would ever consider buying a gasoline hybrid. A diesel hybrid is another story.
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Considering that all the locomotives today are diesel electric hybrids, it beggars the question why manufacturers haven't been doing this ages ago. I guess the planned obsolescence paradigm is finally crumbling.
I do know that Chrysler (who is on death's door apparently) had a diesel hybrid over 10 years ago that have fantastic mileage, in the 70-80mpg range.
The Dodge Intrepid ESX series of hybrid electric cars
Shame that the low hanging fruit of cheap oil at the time killed the project.
I do know that Chrysler (who is on death's door apparently) had a diesel hybrid over 10 years ago that have fantastic mileage, in the 70-80mpg range.
The Dodge Intrepid ESX series of hybrid electric cars
Shame that the low hanging fruit of cheap oil at the time killed the project.
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Ummm…..with regard to railway locomotives they are NOT diesel electric hybrids.
While virtually all American locomotives are indeed diesel electric (diesel prime mover driving thru an electric transmission) they are in no way “hybrid”. Ie. they have no way to temporarily store braking energy that can then be released when power is again required.
Perhaps you are confusing hybrid operation with locomotive dynamic braking? This converts the locomotive traction motors to work as generators to provide braking effort. The energy thus generated is converted to heat in resistor grids mounted on the locomotive’s roof, then grids in turn cooled by forcing air over them.
Bottom line the dynamic braking energy is still wasted as heat into atmosphere, same as traditional friction brakes.
There are actually a few in service as short haul/yard switchers:
Hybrid Locomotive Gains Traction
though hybrids don't pencil out economically for long haul apps by rail or road. If you look at the EPA mileage estimates for hybrid autos you will see that the city MPG is better than Hwy. Absent regenerative braking (as in driving hundreds of miles on the interstate without touching the brake pedal) the parasitic loss of operating a gas or diesel IC engine to turn a generator to turn an electric motor to turn the wheels is not as efficient as the conventional drivetrain of an IC engine mechanically coupled to the wheels.
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There are indeed a handful of diesel-electric hybrid locomotives in yard switching service. However railroads are finding - at least so far - hybrids' higher initial cost and maintenance requirements pretty much offsets the reduced fuel consumption. And with diesel fuel prices half what they were just 8 months ago the economics are simply are not there yet.
Also FWIW: One major manufacturer of hybrid locomotives (RailPower Technologies) filed for bankruptcy only last week. And to the best of my knowledge the other manufacturer (General Electric) catalogs and has demonstrated a hybrid locomotive - but they have yet to actually sell one.
So for the moment anyway I don't expect to see diesel hybrid locomotive sales taking off. But a diesel hybrid automobile may be a technology whose time is about at hand...
I agree...I would consider a grocery getter small diesel electric hybrid with 120V plug-in capabilities and the roof, trunk lid and hood covered in solar cells.:thumbsup:
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Economics isn't what prevents Railpower locomotives from being used for long-haul freight, it's physics.
Railpower builds a switching locomotive with 2,000-Hp traction motors, a 200-Hp Diesel engine and a 100,000-pound battery pack. In stop & go yard duty, the "small" Diesel engine has more than enough power to keep the batteries topped off. In line service, the batteries would quickly be depleted and you'd then be trying to haul a 5,000-ton train with a 200-Hp locomotive.
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What you say about electric drives is true: 20-30% of the input energy is lost in conversion, compared with 2-3% for a pair of gears in mesh and almost nothing for a driveshaft.
But the electric drive enables the engine and road speed to be decoupled so that the engine can run closer to its "sweet spot", many hybrid powertrains (parallel) use mechanical power transmission while cruising, and adding hybrid hardware enables you to achieve the same acceleration performance with a much smaller engine.
Toyota Camry, 2.4-liter engine: 31 highway mi/gal
Toyota Prius, 1.5-liter engine: 45 highway mi/gal
Good points, but a better "apples to apples" comparison would be the conventional Camry (21/31) with the hybrid Camry (33/34).
2009 Toyota Camry car trim and prices
Also note that the hybrid commands a $7000 premium and unless most of your driving would be city it would be years before the 3 Hwy MPG hybrid advantage makes sense. There is also the battery pack replacement to be amortized into the equation (assuming you keep the car that long).
I am all for hybrids in the proper applications and would consider one for a city car. As I recall, Navistar was experimenting with a hydraulic hybrid truck for frequent stop and go apps like garbage trucks...seems like a natural to me but I've not seen any more about it for a few years.
If you look at the Peterbilt website they currently show four hybrid truck models, ranging from utility and garbage haul type trucks all the way up to a sleeper-cab tractor. The local utility company here in Raleigh has a couple of hybrid line trucks that I've seen tooling around town...now they just need to figure out how to charge it off of the powerlines while they're on a service call.
That sounds opposite (but similar to) the calculation/rationalization most of us made about the cost premium for the diesel engine. Sure it (the diesel) costs an extra $5000, but it'll probably last 200k miles longer than a gasser, and should have a comparably higher resale.
-RD
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What better illustration that if you don't downsize the engine, you don't get the full benefit of a hybrid installation?
I am more than a little curious: The Camry hybrid is the same car, same engine, presumably more weight and achieves 10% better highway fuel economy? What's different?
Diesel hybrid
Last year... or maybe earlier... right after Chrysler was sold to a private group by Daimler, the CEO of Daimler... the guy with the walrussy mutache, announced that Daimler would have a "Mild diesel hybrid" in 2010 in the U.S. in their large sedan and he expected it to get 44MPG. It stuck in my otherwise mushy memory because I thought at the time that the RR's had figured this out about 60 years ago.
Now... not sure what "Mild" means, but I would suspect it just means a diesel-electric with no regenerative battery charging.
And just for grins, I remember a diesel 4-door 4-passenger Rabbit back in the late 70's that got about 50MPG on the road.
There's exciting times ahead with new and amazing things to come. That one of the things I'll miss when I punch out.. seeing all the things people invent to address the needs and wants of the market.
Florida Ed
Last year... or maybe earlier... right after Chrysler was sold to a private group by Daimler, the CEO of Daimler... the guy with the walrussy mutache, announced that Daimler would have a "Mild diesel hybrid" in 2010 in the U.S. in their large sedan and he expected it to get 44MPG. It stuck in my otherwise mushy memory because I thought at the time that the RR's had figured this out about 60 years ago.
Now... not sure what "Mild" means, but I would suspect it just means a diesel-electric with no regenerative battery charging.
And just for grins, I remember a diesel 4-door 4-passenger Rabbit back in the late 70's that got about 50MPG on the road.
There's exciting times ahead with new and amazing things to come. That one of the things I'll miss when I punch out.. seeing all the things people invent to address the needs and wants of the market.
Florida Ed
One point is that the Prius and Camry are in a different league re ride, creature comforts, amenities etc, so comparing the two is a bit misleading. I doubt that a Camry hybrid with the 1.5 L Prius engine would be very marketable or drivable.
Another point would be that one must pay an almost 40% initial price premium for basically the same car with the hybrid vs conventional drivetrain, plus factor in the eventual cost of a replacement battery pack (I've seen a figure of +/- $5000 quoted). If that is indeed the case, the consumer is paying approx a 60% premium ($32K vs $19K) for the same car with a different propulsion system.
I'm not sure how many miles, years or charge/discharge cycles the hybrid battery pack is good for but I do know that I bought a 1995 Toyota pickup new that is now on its 4th or 5th owner and last I heard it had 200K+ miles with just normal service items replaced.
When looking at raw MPG numbers one must remember the old adage "Penny wise and pound foolish".:thumbsup:
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There's no definition or consensus what "mild" means. I'm pretty sure GM introduced "mild" when they introduced their BAS (belted alternator/starter) hybrid system. It uses a 5-kW (7 Hp) motor/generator belt-coupled to the engine.
"Mild" doesn't refer to a missing feature such as regenerative braking, it refers to magnitude of the overall effect.
A 7 Hp motor/generator coupled to a 150 Hp engine might seem so mild as to be hardly worth the effort, but remember that 150 Hp is a peak rating, at 6000 rev/min. When driving, the engine's speed is more like 3000 rev/min, at which point it delivers maybe 80 Hp.
So the overall effect is to add 7 Hp to 80 Hp, (not to add 7 Hp to 150 Hp) which is ... still pretty mild, I guess.
A diesel should not cost $5000 more than the equivalent diesel. For example, we just bought a BMW X5 35d. It was $4000 more than the 3.0 engine. But the 35d version is not "equivalent" to the 3.0 spark ignition engine. It's closer to the 4.8 V8 (75 ft-lb more torque than the V8) which is $4K more than the diesel.
The equivalent engine to the 35d twin turbo diesel is the 35i turbo petrol 6. Compare the price of a 335d to a 335i - the difference is $3600 - and I think they are pushing it up too much. And it puts out way more torque, ~150 ft-lb more. Of course it does 10mpg better (36 hwy).
The equivalent diesel to the 3.0i petrol 6 is the 30d version; not sold in the US. Research will show that both Mercedes and BMW charge no more 1000 euros more for the equivalent diesel to a petrol motor, at least in Europe.
You can in no way say that a Cummins 6.7L 24 valve six with 650 ft-lb is equivalent to a petrol V8 with 40% less torque. Incidentally, the medium truck engines Detroit has been putting in pickups are a classic case of overkill IMHO. No wonder they charge $5000 more for them.
Charlie
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