Reader Question: “Tier 3” Gas?

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Here’s the latest reader question, along with my reply!

Kenneth writes: The company that I have been working for in Utah is encouraging its employees to take on the “Clean Air Challenge” and one of their suggestions is to use “Tier 3 gas” at gas stations that provide it, which is apparently many gas stations in the area including Chevron and Shell. They call it a “magical, cleaner gas.” So, is Tier 3 gas truly cleaner?  Is it good for your car, neutral, or does it do harm in the long term?  What are your thoughts on Tier 3 gas? This is the link that the company provided to find more information about Tier 3 gas.

My reply: Tier 3 gas is touted as having lower sulfur content and being able to reduce “harmful emissions” (of particulates and ozone) by “80 percent” in newer cars (2017 and up)  and “12 percent” in older cars.

My bullshit detector just went off.

First, I’d like to know what, precisely, “80 percent” (and “12 percent”) refer to. Are we talking about an 80 percent (and 12 percent) overall reduction? Or a reduction of the small portion of vehicle exhaust emissions that has not been “controlled”? This latter is the shuck and jive used for years to make grand-sounding claims to justify high imposed costs. But when you dig into it a little, you discover that “80 percent” means 80 percent of .5 percent (or similar) and so a negligible difference, often at great cost.

Is there are any benefit to you – the driver – to be had from using this Tier 3 gas? Not i f it costs substantially more than other gas, or contains less energy due to higher ethanol content – which will mean reduced mileage.

Which, as it turns out, is just what Tier3 fuel will do. See here.

Here’s what the EPA touts about Tier3 gas.  I take everything the EPA touts with a bucket of salt and while constantly mantra’ing to myself that the purpose of the EPA is not to “clean the air” but to perpetuate and expand its authority, as is true of all bureaucracies.

. . .

Got a question about cars, Libertarian politics – or anything else? Click on the “ask Eric” link and send ’em in!

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  1. eric, refineries actually use energy to distill petroleum, hard to believe I know, but it’s true. So how much more in refinery costs does Tier 3 fuel require? There’s a reason rail lines are run into refineries, to haul the unwanted materials away, the greatest part is sulfur.

    I read an article one day in a trad mag for the patch that the amount of sulfur now removed from fuel is enough for every sulfur need in the country. That’s a good deal I suppose but how come the area out in far west Texas and N.M. where the huge sulfur plant and wells are located never slows down? So where do the sulfur from refineries go if there’s enough sulfur to supply all the needs in this country coming out of refineries? It’s wondered this since “low sulfur” diesel became the order of the day back in ’07. And they wonder why I always used “off-road use diesel” whenever I could.

    It was like, Hey everyone with older diesels, go find you some other diesel but the state will fine the whee out of you for using “farm diesel” in your older road diesels.


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