Progressive Automotive X-Prize Knockout Round

by Neil on July 1, 2010

I think that the X-Prize competition is fulfilling the objective of focusing on vehicle efficiency.  Starting with the results so far, I am hoping to contribute to the discussion and to the process.

Here’s the link to the PDF that shows the results of the X-Prize Knockout Round.

The measured MPGe of the teams in this round — remember this is the Combined number from the City, Urban, and Highway tests:

American HyPower    54.5    Hybrid
Spira        84.8    ICE (E10)
FVT eVaro        152.5    Hybrid (serial)
Zap        111.0    EV
Tata        134.3    EV
Electric Raceabout    128.1    EV
AMP         86.7    EV
West Philly (MS)    63.5    Hybrid
West Philly (Alt)    53.7    Hybrid
Global-E        50.4    Hybrid
Li-ion         182.3    EV
Aptera        140.1    EV
TW4XP        107.0    EV
WWU        92.5    Hybrid
Tango        86.8    EV
BITW        51.1    ICE (diesel)
X-Tracer (#72)    180.0    EV
X-Tracer (#79)    188.8    EV
Illuminati        119.8    EV
Enginer        53.0    Hybrid (electric/ICE w/ steam heat recovery)
Edison2 (#95 Alt)    97.0    ICE (E85)
Edison2 (#97 MS)    101.4    ICE (E85)
Edison2 (#98 MS)     80.3    ICE (E85)

I think these results speak for themselves!  The electric cars are in general, giving much better efficiency, and several of those (the X-Tracer, FVT, Tata, and the Aptera) also have excellent acceleration.  The Li-ion,  Illuminati, TW4XP, and Edison2 (among others) were not as quick — the Li-ion and Edison2 cars are through to the finals, though.  I am sad that neither the FVT eVaro nor the Illuminati Seven made it through, due to (relatively) minor technical reasons.  They failed at the moment (which is how racing/competitions work, to be sure), but I think their problems are solvable, and the strong merits of their vehicles are obvious.

The Aptera is through, but still a bit disappointing — it’s aero is equal or better to anybody (save the X-Tracer), but their efficiency seems to have suffered.  It barely betters the Tata, which is “just” a well executed EV conversion of a decent but ordinary hatchback.  The Global-E had an ignition mapping error that made their number lower.

So the lowest MPGe of an electric drive; the AMP’d Sky was 86.7MPGe (Tango was 86.8), while the best of a car with an internal combustion is the Edison2 #97 at 101.4.  (Actually, the FVT has a ICE powered generator onboard, but did not need it *at all* in the X-Prize. It would be great to see how the eVaro does for MPGe in charging mode!)  The hybrids all were all below the 67MPGe — except the WWU at 92.5 (and the FVT).

The average of the 12 vehicles using electric drive MPGe (I’m including the FVT in this) was 134.7MPGe
The average of the 6 hybrids (not including the FVT) was 61.26MPGe (please note, these are all parallel hybrids?)
The average of the 5 internal combustion drive cars was 82.92MPGe

The X-Prize results table does not include weights, but I daresay that the average weight of the internal combustion cars was lowest (the Edison2 and Spira are all much lighter!).

The best aero drag is on the X-Tracer, followed by a very close group including the Aptera, Edison2, Li-ion.

As many have said, the X-Prize is setting a very high standard (which is both good and bad).  They are essentially looking for the complete package, and virtually no glitches.  Even the well financed/professional teams had several glitches.  I would have set up the X-Prize a bit differently; to measure (and therefore emphasize and encourage) the four main things that need to be improved to get the maximum efficiency.

Those four critical things are; from most important to least important (as I am interpreting the Knockout results):

* Drivetrain Efficiency
* Aerodynamic Drag
* Weight
* Rolling Efficiency

I would have scored these in relative terms, which pits each vehicle against the others (rather than setting standards that are somewhat arbitrary).  On drivetrain efficiency, I would either use a dynamometer or the best result of the three economy tests: the City, Urban, or Highway.  (This will indicate what vehicle is good for a particular role, and measures the drivetrain at it’s best.)

For Drivetrain Efficiency, the points awarded would be the best MPGe x Number of Seats.  So, using the Overall MPGe for 23 vehicles that competed in the Knockout Round listed above (we do not have the separate measured results from the City, Urban, and Highway test): the X-Tracer #79 would be 188.8 x 2 = 377.6 points, and so on.  The best mainstream MPGe was the Illuminati Seven: 119.8 x 4 = 479.2 points.

Aerodynamic Drag would use the Weight and the Rolling Efficiency, and the results of a Coastdown test to determine the Cd of each car.  I would take the inverse of the number of entrants divided by the Cd, then multiplied by the Number of Seats: So the Aptera and the Li-ion and the Edison2 alternate cars may be at the top: 23 (22, 21) / 0.15 x 2 = ~306.6 and ~293.3 and ~280 points respectively.  The Edison2 mainstream cars would get 20 and 19 (or higher depending on their Cd) resulting in 20 (19) / 0.15 x 4 = 533.3 and 506.6 points respectively.

For Weight, I would take the lightest one and score it by inverting the number of Entrants x the Number of Seats – the Spira would get 23 x 2 (seats) giving it 46 points.  The Edison2 alternate car would be next with 22 x 2 = 44 points.  The two Edison2 mainstream cars would be 21 x 4 = 84 points and 20 x 4 = 80 points respectively; and so on.  This give priority to the cars that seat more people, and it is realistic in terms of what is achievable in the real world.

Rolling Efficiency includes tires and alignment and would be prorated for weight – a slower coastdown test using a ramp would be needed.  I think an inverted number of the entrants would be a fair way to award points.

Obviously, all four of the critical factors are interrelated, and they all would be reflected in the Overall MPGe number – but testing for them and awarding points (in some manner) for them separately, helps focus the designs on the most important aspects – and more importantly helps demonstrate their performance; whether or not the designs get ALL of them right and in the right balance, and if there is something that lags (or breaks) and the vehicle is DQ’d, people will still be able to judge the merits of the design.

We could quibble about how each of these was scored – I am just throwing this out there.  At this moment in time, I feel that the emphasis on the safety, and meeting the letter of the rules, etc. are  distracting the designers from the main point; of maximizing the efficiency.  Obviously, for a finished, production, reasonably priced, appealing vehicle – ALL of these things are also critically important.  These would be determined by finished vehicle, and the buying public.  But, I feel that an emphasis on the overall efficiency, and the four most important factors that directly contribute to maximum efficiency, would have better served the purposes of the X-Prize.

One of the most important things I learned while I was at the X-Prize Knockout competition was: do not dismiss or ignore anybody!  There is a LOT more than meets the eye with all of the entrants, and no matter the results, all the designs have strengths – and weaknesses that are all very informative.

I also was floored by the height of passion by so many people.  The sight of Oliver Kuttner with tears streaming down his face; returning from the starting line of the City Test with the first of his cars about to actually get to the heart of the matter; moves me to tears, as well.  And I’m quite sure that every person involved in the X-Prize, who has put in a similar Herculean effort, feels the same.

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{ 7 comments }

1 Lisa Neulicht July 1, 2010 at 10:20 pm

To clarify: The V45 is from WWU -Western Washington University not WSU.

2 Roger Riedener July 3, 2010 at 6:05 am

Hi Neil, txs for the good summary on Knockout at X-Prize. As team leader and driver for the two X-Tracers, i have some comments to make. I drove #79 faster than any other competing vehicle in the highway efficiency and the range test, because i understood that it will at the finals be “the fastest vehicle that still achieves 100 mpge” according to the rulebook of the X-Prize. Unfortunately, they have not published our averaged speeds, which were between 5 and 10 mph higher (always just 0,2 mph lower than the maximum allowed average speed, which in itself is a contradiction to the rulebook…) than most others, therefore we lapped every other vehicle on those 45 laps of the highway or the 34 laps of the range test. We will make sure that in the finals, these tests are conducted to the rulebook and none of the “make-them-equal” stuff remains in the criteria. We are also reminding everybody of the fact, that both our X-Tracers have swiss street approval, not just as prototypes, but as the electric version of our MonoTracer, which has full EU COC (certificate of conformity) registration and is fully DOT/EPA approved in the USA. We had the demonstrator MonoTracer of our US distributor, Jim Lorimer of 21st Century Motoring, giving Pace Car rides during the 2-day Wine Festival on the MIS to prove that our entry more than meets the PIAXP requirement of production readiness. Hope to see you at the Finals! Best regards, Roger

3 Jo Dene Romeijn-Stout July 5, 2010 at 2:17 pm

Thank you for this blog. My son is on the WWU team, which you incorrectly identified as the WSU team. Both are universities in Washington state, but they are in opposite corners of the state. The X-Prize team with the car called Viking 45 is from WWU which is Western Washington University in Bellingham, Washington. I am very proud of the work done by my son and the entire WWU team, and very please that there is such a competition striving to produce more ecologically sound cars.

4 Neil Blanchard July 5, 2010 at 2:37 pm

Sorry about the error on the name of the university — I had realized my mistake, but not managed to change it in all places. I got to talk to a couple of the WWU team, and I came away very impressed with the work they have done.

And Roger, thanks for the additional info — in some areas, the rules are harder to distill, that is for sure.

Sincerely, Neil

5 Roger Riedener July 5, 2010 at 10:49 pm

Neil, here at Peraves, where we have been obsessed with the high performance cabin motorcycle for 26 years, we naturally have a different view of things and have our “own” eco-modder-index. We call it VED, short for Vehicle Eco-Dynamics: just divide the averaged mpge by the accelleration time 0-60 mph!

X-TRACER 79 Tandem 188.8 MGPe : 5.50 sec = 34,32
X-TRACER 72 Tandem 180.0 MPGe : 6.30 sec = 28,57
RaceAbout Side-by-Side 128.1 MPGe : 8,40 sec = 15,25
Aptera Side-by-Side 140.1 MPGe : 10.63 sec = 13,18
Tango Tandem 86.8 MPGe : 6.96 sec = 12,47
Zap Side-by-Side 111.0 MPGe : 9.13 sec = 12,16
Tata Side-by-Side 134.3 MPGe : 11.72 sec = 11,46
Li-ion Side-by-Side 182.3 MPGe : 17.90 sec = 10,18
Edison2 #97 Mainstream 101.4 MPGe : 15.00 sec = 6,76
TW4XP Side-by-Side 107.0 MPGe : 17.09 sec = 6,26
Edison2 #95 Tandem 97.0 MPGe : 16.89 sec = 5,74
Edison2 #98 Mainstream 80.3 MPGe : 14.20 sec = 5,65
Spira Side-by-Side 84.8 MPGe : 16.67 sec = 5,08
W.Washington Side-by-Side 92.5 MPGe : 17.54 sec = 5,27
AMP Side-by-Side 86.7 MPGe : 17.85 sec = 4,85

This is what we are all about. Our X-Tracers were not built to be the best green or electric vehicles, but to eat the “smokers” for breakfast…;-) cheers, Roger

6 Neil Blanchard July 6, 2010 at 2:46 am

Thanks Roger — I have been aware of the Peraves for many years, from Cycle World, etc. I rode a BMW K75S for about 80K miles. Do you also have the acceleration time of FVT eVaro? I also hope that the X-Prize folks can release the MPGe numbers for all the vehicles in each of the tests, not just the overall MPGe.

Please not that the original blog post has been edited to correctly name WWU! 🙂

Sincerely, Neil

7 Roger Riedener July 6, 2010 at 6:52 am

Neil, the Canadian FVT Team, who unfortunately did not pass emissions testing (for an ICE they actually did not need anymore, if i understood things right) are a very serious and great bunch of guys, we had a very good time together and they were always happy to share their tools with us at the garage, because we just could not bring everything along from Switzerland. The eVaro goes pretty well, i don’t know their times, though, but i followed it for some laps on the twisty durability test at shakedown and the thing has good roadholding. They seemed to be pretty unlucky and i felt sorry but did not have the opportunity to speak to them before they left and to also thank them for their much appreciated help. (and the ride to the track when my buddy overslept…) Roger

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