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The Electric-Vehicle Cheating Scandal

12 点作者 MilnerRoute超过 1 年前

9 条评论

Stratoscope超过 1 年前
<a href="https:&#x2F;&#x2F;archive.is&#x2F;rxYnQ" rel="nofollow">https:&#x2F;&#x2F;archive.is&#x2F;rxYnQ</a>
Animats超过 1 年前
I&#x27;m trying to figure out where this figure comes from. The immediate source is the Institute for Energy Research, which seems to be a lobbying organization for the oil and gas industry.<p>Not clear what &quot;efficient&quot; means in this context. All heat engines have a second law of thermodynamics efficiency limit. Cars run 20%-40% efficient, measured by dynamometer output at wheels &#x2F; energy content of fuel.[1] (Motor Trend says 20%. [2]) Electric cars aren&#x27;t limited in that way, and reach 63%-80%. Of course, if fuel was burned to create electricity, there was a thermodynamic efficiency loss upstream. Those values have objective engineering measurements.<p>There&#x27;s something called &quot;Miles Per Gallon Equivalent&quot;.[3] This is more of a marketing&#x2F;regulatory term. It appears on car window stickers. It&#x27;s just miles per kilowatt hour multiplied by kWh per gallon of gasoline, which is 33.7 kWh &#x2F; gallon. Motor Trend says that the Tesla Model 3 is rated at 142 MPGe, which is a reasonable number.<p>This probably has to do with pollution credits, not energy efficiency. It&#x27;s may be related to the Corporate Average Fuel Economy rules. Those have a big loophole on the gasoline-powered side - there are different limits for &quot;cars&quot; and &quot;light trucks&quot;.[4] US vehicle production is currently over 50% &quot;light trucks&quot;, which includes many SUVs.<p>[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Engine_efficiency" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Engine_efficiency</a><p>[2] <a href="https:&#x2F;&#x2F;www.motortrend.com&#x2F;news&#x2F;evs-more-efficient-than-internal-combustion-engines&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.motortrend.com&#x2F;news&#x2F;evs-more-efficient-than-inte...</a><p>[3] <a href="https:&#x2F;&#x2F;www.motortrend.com&#x2F;features&#x2F;what-is-mpge-meaning" rel="nofollow">https:&#x2F;&#x2F;www.motortrend.com&#x2F;features&#x2F;what-is-mpge-meaning</a><p>[3] <a href="https:&#x2F;&#x2F;www.kbb.com&#x2F;car-advice&#x2F;what-is-mpge&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.kbb.com&#x2F;car-advice&#x2F;what-is-mpge&#x2F;</a><p>[4] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Corporate_average_fuel_economy" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Corporate_average_fuel_economy</a>
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cbsmith超过 1 年前
Someone in the comments explained what&#x27;s really going on here (and it isn&#x27;t cheating, though perhaps one might see it as a scandal):<p>&quot;The 6.67 factor is based on 1.00&#x2F;0.15. The intention was an incentive for 15% of the fleet to be alternative fuel vehicles in the 1990&#x27;s such as compressed natural gas (CNG), ethanol, etc. In this way if Ford had 15% of their fleet on CNG, then they would be equally weighted to their gasoline fleet in the fuel economy calculation by the EPA. The 15% incentive was supposed to be phased out as the actual percentage increased over time.&quot;
rdtsc超过 1 年前
&gt; Carmakers and regulators liked it that way. Regulators could announce what sounded like stringent targets, and carmakers would nod along, knowing they could comply by making electric cars with arbitrarily boosted compliance values. Consumers would unknowingly foot the bill.<p>Brilliant. Both sides were having fun until someone ruined their party.<p>I would also expect a much more tame reaction compared to Dieselgate. Everyone, including the journalists, will probably justify it that the end, getting rid of fossil fuels vehicles, justifies the means, a little cheating here and there.<p>Who knows maybe they are right. But then they also get to write articles about how people don’t trust the government and the media as much as they used to for some strange reason.
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aksss超过 1 年前
Some weedy detail, for those interested. This is the notice of the proposed rule change (NOPR) for the 6.67 number.<p><a href="https:&#x2F;&#x2F;www.federalregister.gov&#x2F;documents&#x2F;2023&#x2F;04&#x2F;11&#x2F;2023-06869&#x2F;petroleum-equivalent-fuel-economy-calculation" rel="nofollow">https:&#x2F;&#x2F;www.federalregister.gov&#x2F;documents&#x2F;2023&#x2F;04&#x2F;11&#x2F;2023-06...</a><p>Also, I think this article from 2019 really adds some missing details, like how the carbon credit exchange works.<p><a href="https:&#x2F;&#x2F;thehustle.co&#x2F;09042019-carbon-emissions-credits&#x2F;" rel="nofollow">https:&#x2F;&#x2F;thehustle.co&#x2F;09042019-carbon-emissions-credits&#x2F;</a>
Drive-by超过 1 年前
&gt; Economists estimate these credits could be worth billions: a vast cross-subsidy invented by bureaucrats and paid for by every person who buys a new gasoline-powered car.<p>The piece asserts that buyers of new ICE cars pay this subsidy, but has no description of how new car buyers pay it. Do they really? How much is it? How does that compare to the externalized costs of burning gasoline?
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saagarjha超过 1 年前
Sorry, I might be missing something. What does mpg even mean for an electric vehicle? When measuring efficiency I typically see miles&#x2F;kWh, which to my knowledge is not fudged (except for “this may not match real-world driving” etc.)
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Roark66超过 1 年前
Wait, it makes no sense, but let&#x27;s run our own mpg numbers. I&#x27;ll start in L&#x2F;100km as that&#x27;s what I&#x27;m used to and I&#x27;ll convert it at the end. My 19 year old VW golf Mk5 4*4 (hatchback) does 4.5L&#x2F;100km or 43mpg on a highway. Now let&#x27;s take Tesla&#x27;s M3 real world tested 14.5kWh&#x2F;100km (at 70mph on a motorway). Each liter of diesel contains 9.16kWh so this is essentially 1.58L&#x2F;100km or 148mpg which is not bad at all for a 2+ ton vehicle. So where did the 68mpg value they supposedly multiply by 6.6 came from?
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tgv超过 1 年前
I don&#x27;t get it. There&#x27;s no environmental gain in popularizing electric cars when they are inefficient, so what motivates the Transportation Department? I also don&#x27;t understand what the significance of mpg in this context is. Electricity doesn&#x27;t come in gallons. Subsidizing producers for meeting arbitrary criteria also doesn&#x27;t make sense.<p>So, to me, it looks like someone decided to subsidize electric car manufacturers, and just needed an excuse in some legal framework. There might be a scandal there (e.g. bribes), but 6.67 factor ain&#x27;t it.
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