SparkEV is the most efficient car in the world

[SparkevBlogspot]

Doing some research, I find that SparkEV is the most efficient car in the world, EPA be damned. Details are in my blog post. I don't know why it took so long to realize this when the facts were staring me in the face all this time.

http://sparkev.blogspot.com/2017/02/sparkev-is-most-efficient-car-in-world.html

 

[PhilPen]

Great post I really enjoyed reading that.

 

[Zoomit]

The post really confuses me as you use MPGe from the EPA but then talk about energy efficiency while driving. The EPA fuel economy data, provided as MPGe, includes charging losses. Do you think charging losses should be considered when defining the "most efficient" car?

Think about it like filling up a gas car and pretend there's a leak in the pipe between the filler receptacle in the car and the gas tank. Is the most efficient car the one that goes the furthest based on the number of gallons of gas purchased or the number of gallons used from the gas tank?

 

[SparkevBlogspot]

I cover charging losses in the blog post. Even if you assume all other cars are battery to wheels (not including charging loss) and SparkEV outlet to wheels (including charging loss), SparkEV comes out ahead in 70 MPH test. It seems incredible, I know, just like 6 mi/kWh average over 10K miles some claim with SparkEV seems incredible. But given the data I found, that's what it is.

 

[Zoomit]

But you don't have rigorously-controlled test data and you don't have equivalent IONIQ electric data.

Actually you do but choose to ignore it.

 

[SparkevBlogspot]

I discuss this. Quote from my blog, "How trustworthy are these number from various forum posts? I leave it up to the reader to do deeper research."

As for Ioniq, there is no data to ignore. I discuss why EPA rating should not be used pretty early in the blog post. I also discuss why it would be hard to beat SparkEV efficiency (weight, area, drive train). Besides, Ioniq BEV isn't yet available in US, though Insideevs article has it supposedly coming out this week.

 

[Zoomit]

Simply put, but ignoring the difference in charging losses between cars (and now by ignoring cars availability worldwide), your conclusion that the "Spark EV is the most efficient car in the world" is fundamentally flawed. Your caveats are too significant to lead to your categorical conclusion.

 

[SparkevBlogspot]

It's a fallacy to say you can't draw conclusions until you have 100% of every possible data available. From the data available, SparkEV is the most efficient car in the world. Even if future cars become more efficient than SparkEV, SparkEV was available from 2013, so it will be historic in that it is the most efficient car from 2013 to whenever the more efficient cars arrive.

Even if you take into account charging losses, SparkEV is more efficient than any car in the universe. See the response I gave you before, and also described in the blog.

If you doubt that SparkEV is the most efficient car in the multi-verse, provide the evidence to the contrary in the scope of testing done in the blog. Obviously, you can make up whatever you want by turning on the AC/heat, opening the windows, stopping hard often to use friction brakes like the way EPA does it, but that's not what I'm talking about. Test conditions are described in the blog: slight up hill, about 400 lb "cargo", cruise control, etc.

By the way, what is beyond multi-verse? I'm running out of scope.

 

[Zoomit]

In the universe I live in, a car's efficiency is best described as the distance able to be traveled given a quantity of supplied energy. That distance should be under a combination of conditions, with varying speeds and representing typical usage. Car efficiency data would be collected by a standardized, repeatable, rigorous test processes where the manufacturers, which provide the data, are accountable for both willful or unintended errors. The most commonly-accepted car efficiency test is administered by the EPA and meets above criteria.

Here are the current top 5 highest-rated cars, in terms of EPA-rated combined fuel economy:
http://www.fueleconomy.gov/feg/topten.jsp

IONIQ Electric, 136 MPGe
i3 60Ah, 124
Bolt EV, 119
e-Golf, 119
i3 94Ah, 118

The Spark EV was rated at 119 and would have tied for 3rd

If we want to bias the rating to the EPA Highway Fuel Economy, the top 5 turn to:

IONIQ Electric, 122 MPGe
i3 60Ah, 111
e-Golf, 111
Bolt EV, 110
i3 94Ah, 106

The Spark EV was rated at 109 and would have been 5th.

If we jump to a different universe, where "most efficient" is defined as the battery energy consumption at a steady 70mph and only provided by "real world" owner data, the available data on the IONIQ Electric should be considered. Here's an example of a gentleman that went 70 mph for 44 miles downhill using using 29% of the 28 kWh battery. His uphill 56mi return used 39%.
https://speakev.com/threads/hyundai-ioniq-electric-range.21219/page-2#post-384063

That works out to 5.3 mi/kWh [(44+56)/(0.29+0.39)/28], which is a very respectable number given it's 19% more efficient than a Spark EV at 4.4 mi/kWh!

Here's additional IONIQ data, if curious: https://docs.google.com/spreadsheets/d/1qWBNTSDmwD53NUSq66dJdlm_QMRwrj9K6d8OYZGMhMQ/edit#gid=0

 

[SparkevBlogspot]

As I mentioned in the blog, EPA number is meaningless. It's like I see a green apple, others (ie, Tony Williams) see a green apple, but I tell myself and everyone else that the apple is red because EPA says so. That's nonsense.

Biggest problem with EPA rating is that it's a hodge podge of some arbitrary "stuff" and not enough granularity. The test I and Tony Williams perform is least variable possible given the circumstance. What EPA should do is produce graph like I made: mi/kWh over speed and added power use (also over temperature) which shows what the car is capable of with and without hodge podge. In effect, looking at EPA is like looking at box of chocolates: you never know what you get.

For example, I got 5.3 mi/kWh average after 16K miles. Assuming 80% efficient charging (L2 is actually over 85%, DCFC over 90%), that works out to 4.24 mi/kWh, or 142.9 MPGe with 33.7 kWh/gal. That's over 30% better than EPA's 109 MPGe. For some who got over 6 mi/kWh (4.8 mi/kWh after 80%, 162 MPGe) after 10K miles, that's almost 50% better than EPA rating. Box of chocolates and red apples, indeed.

To be fair, EPA rating works "ok" with gas cars. Every gas car I've driven was close to EPA rating, though rarely any ever got above it. EPA was bit optimistic when it came to gas cars, but they're way pessimistic random number when it comes to EV, at least with regard to SparkEV, probably others as well; you can't capture efficiency that could vary by over 90% with just two numbers.

However, forum post you link is interesting. It does seem to show Ioniq beating SparkEV in efficiency at 70 MPH. But if you read further down, another posted "In 5 degree temperature at up to 60 mph motorway I got 147 miles. Shows 4.9 miles/kWa on the trip".

https://speakev.com/threads/hyundai-ioniq-electric-range.21219/page-5#post-396857

The battery is 147/4.9 = 30 kWh, not 28 kWh. Then doing the math with % used at 70 MPH gives 5.06 mi/kWh and 4.79 mi/kWh. That's still better than SparkEV at 70 MPH. But Tony Williams got 5 mi/kWh with SparkEV at 62 MPH while Ioniq "up to 60 MPH" got 4.9 mi/kWh, which is better than Ioniq. Tony was running more favorable close to 20C, so the jury is still out.

Even if Ioniq or another car turns out to be more efficient than SparkEV, that doesn't change the fact that it was the most efficient car in history up to that point. Records are meant to be broken.

 

[SparkevBlogspot]

The spreadsheet you link is even more interesting. At 70 MPH at 7C temperature is 4.9 mi/kWh (30 kWh battery as shown by 60 MPH post), but 2C is only 3.67 mi/kWh at 70 MPH. Similar pattern emerge at other temps where "slightly" lower temp result in drastic decrease in efficiency. Most are about 3C, so those results cannot be compared to SparkEV test. I have to wonder if they run the heater. I have the dogs in the car most of the time, so they're "free" heaters (though they add about 150 lb).

There is one at 21C at 30 MPH that result in 7.3 mi/kWh. That would be more than 2014's 7.2 mi/kWh at 24 MPH, though it's hard to know if that's more than lighter 2015 that hasn't been tested at low speed. This is why I'm waiting until Ioniq is available in US (CA specifically) to see how well it will do.

If EPA or someone test it like my test (or Tony Williams) in CA and produce a graph of efficiency over speed, that would be the best comparison. I don't know if there are enough Ioniq fans who'll go through the trouble. If SparkEV is boring like Leaf or Ioniq, I don't think I'd be as jazzed about it as much.

 

[PhilPen]

Unfortunately EPA listed mileage numbers are not strictly comparable with each other for a number of reasons (many are conducted in the manufacturer's own non-standardized labs, companies are allowed to use data from one power-train when it gets placed in a different chassis, some car makers purposefully exaggerate mileage estimates). For this reason the EPA wants more real world tests. This could be relatively easily accomplished these days by having consumer's cars report their data to a third party. The rank order of 'fuel' efficiency of cars with relatively close EPA ratings is likely to vary considerably based on the test environment, and the EPA ratings themselves likely contain significant wiggle-room.

https://consumerist.com/2014/07/15/epa-wants-car-companies-to-test-gas-mileage-in-real-world/

 

[SparkevBlogspot]

To be fair, EPA rating works "ok" with gas cars. Every gas car I've driven was close to EPA rating, though rarely any ever got above it. EPA was bit optimistic when it came to gas cars, but they're way pessimistic random number when it comes to EV, at least with regard to SparkEV, probably others as well; you can't capture efficiency that could vary by over 90% with just two numbers.

So my assertion that SparkEV is the most efficient car in the world and in history still stand, EPA be damned. As mentioned in the blog, Tony Williams real world driving at 62 MPH had SparkEV even more efficient than 22 kWh BMW i3 as well as my test against various forum post. Presumably, forum posters take pride in their cars to do careful tests, and not artificially report it worse. I call an apple a green apple if I see it as green, not a red apple just because EPA says so.