EPRI-DaimlerChrysler Plug-In Hybrid Development Program
03 February 2006
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| A Sprinter PHEV |
EPRI and DaimlerChrysler are about to enter the fleet feasibility testing phase of their investigation into plug-in hybrids with the pending deployment of six Sprinter vans of different configurations in different locations.
Dr. Mark Duvall of EPRI provided a brief update on the project at the recent SAE Hybrid Vehicle Technologies Symposium.
The Sprinter program has a number of objectives:
To design and test a PHEV commercial van with up to 20 miles of electric range (PHEV20);
To collect performance and field test data;
To verify the performance and durability of different types of advanced batteries in a PHEV application;
To use the results to improve design for a Phase 2 production prototype program.
The project is using six vans with different combinations of engine (either 2.7-liter gasoline or a 2.3-liter diesel) and battery (NiMH or Li-Ion). All use the same 90 kW motor.
| EPRI-DaimlerChrysler PHEV Fleet testing Vans | ||||
|---|---|---|---|---|
| Model | Engine | Battery | Location | |
| 1 | Cargo van | Diesel | NiMH | Hannover, Germany |
| 2 | Cargo van | Gasoline | NiMH | Schweinfurt, Germany |
| 3 | Bus body with paratransit equip. | Diesel | Li-Ion | Kansas City |
| 4 | Cargo van | Gasoline | Li-Ion | Los Angeles |
| 5 | Utility van | Gasoline | NiMH | Los Angeles |
| 6 | Cargo van | Diesel | Li-Ion | New York |
The battery packs in these vehicles are large: 14 kWh. By comparison, the Prius has a 1.5 kWh pack. Preliminary estimates give the Sprinter electric performance of 2 miles/kWh.
The motor, at 91 kW peak power (72 kW continuous) and 275 Nm peak torque (130–180 Nm continuous) was selected to support the program’s focus on urban driving—i.e., little if any higher speed driving that would require a motor of > 125 kW.
Optimizing the operating strategies for the vehicles will be a major component of the testing, the goal being to maximize stored battery energy, while balancing operation with low operating costs.
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| Operating limits for electric mode. |
There are a number of possible triggers for mode changes, including vehicle speed, the state of charge (SOC) of the battery, acceleration, location and system temperature.
For this project, the team decided to limit electric operation to speeds below 50 km/h (31 mph) and with a battery SOC from 20%—100%. Although the system could support higher speeds, the battery would deplete more quickly.
On the question of CO2 emissions per electric mile travelled, EPRI estimates that in 2010, the national average CO2 emissions from power plants will be slightly more than 500 grams/kWh.
With the current Sprinter PHEV design, that would work out to about 250 grams per electric mile, or 157.5 g/km of CO2.
According to EPRI, in a base case for future power generation, with no additional nuclear, no carbon capture, and no new renewables, the 500 g/kWh will decline to about 350 g/kWh by 2050.
Depending upon technology and regulatory drivers, that could drop (as a national average) to as low as about 150 g/kWh—clearly offering great potential for simultaneous reductions in both utility and transportation sector CO2.
Clearly, though, the gating factor is the battery.
Resources:
Driving the Solution: the Plug-In Hybrid Vehicle; EPRI Journal, Fall 2005
If a plug-in Sprinter works why not a plug-in full size SUV or full size Chrysler?
Posted by: tom deplume | 04 February 2006 at 09:28 AM
Don't understand why the grams of co2/kw decrease under the base case.
In any event, as long as we're producing hydrogen through reformation of fossil fuels or electrolysis using fossil fuel generated electricity, electric or near electric vehicles seem like the way to go.
Although, hydrogen might start to look better when one starts using wind to produce the electricity, this would be true of electric vehicles as well. At least for the foreseeable future, hybrid or plug in hybrid seems like a more doable and practical approach. I don't understand all the focus on hydrogen, unless it's just a way for the Bush administration to put off really doing anything now about global warming.
Just as a point of reference, the Prius emits 210 grams per mile. While SUVs could improve their grams per mile if converted to PHEV, their output will always exceed the smaller and/or more efficient automobile.
Posted by: t | 04 February 2006 at 11:06 AM
t:
Isn't comparing Prius grams/mile of CO2 with electric vehicle overly simplistic? You'd need to compare the total well-to-wheel emissions for both vehicles, I think. With a green source of electric power, biggest electric van will have lower CO2 emissions than most efficient gasoline hybrid, no matter how small.
Posted by: Nick | 04 February 2006 at 02:19 PM
t: EPRI may be projecting improvements in conventional generation as old units are replaced. FWIW, I don't see where they'd get a 30% cut in emissions either; gas is about to be replaced by coal in a big way, and (if I've read the somewhat-vague reports correctly) even the best IGCC plants with full CO2 capture from the fuel gas don't have that kind of improvement over gas-fired turbines.
Posted by: Engineer-Poet | 04 February 2006 at 08:42 PM
When I said the smaller, more efficient vehicle would emit less co2,I was comparing apples to apples (electric to electric) not a Prius to an electric. I just noted the Prius emission of co2 rate as a point of reference. I don't know how this would all turn out if one considers well to wheel. Both the hybrid's and the electric's emissions would increase if one computed the energy required to produce the sources of energy and all the energy required to produce each type of vehicle.
I agree, obviously, that a green source of power would improve the electric vehicles' emissions.
In any event, for the foreseeable future, we should focus on hybrids, PHEVs, and electrics. All these technologies are in relatively near term reach and all will clearly reduce our emissions of CO2. If we need to prioritize, we should deemphasize hydrogen. The time for action is now.
Posted by: t | 05 February 2006 at 07:05 AM
Tom
a plug-in SUV would "work" however the nitch which Sprinter vans fill makes them a better canidate. Because mostly they do short-distance city runs, transporting internal mail, or equipment, or etc.
So they total miles traveled at a time is generally lower, and the increased cost of the PHEV system can be recouped much more easily.
SUVs don't have this niche luxury, as they have a very broad use range. Not to say that SUVs couldn't benefit... just that it makes more sense to focus on PHEV in such a utilitarian vehicle first. :)
--Ash
Posted by: Ash | 05 February 2006 at 08:11 PM