# EU to US mpg conversion: Air hybrid

**URL:** <https://boards.straightdope.com/t/eu-to-us-mpg-conversion-air-hybrid/701107>\
**Category:** Factual Questions\
**Created:** [October 12, 2014, 3:29pm UTC](https://boards.straightdope.com/t/eu-to-us-mpg-conversion-air-hybrid/701107 "2014-10-12T15:29:37Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\
**Post date:** [October 12, 2014, 3:29pm UTC](https://boards.straightdope.com/t/eu-to-us-mpg-conversion-air-hybrid/701107/1 "2014-10-12T15:29:37Z")

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Peugeot has showcased a hybrid that stores energy from braking as compressed air instead of in a battery - [the HYbrid Air](http://green.autoblog.com/2014/09/23/peugeot-hybrid-air-for-paris-2014/). Per that article it gets 118 mpg US but I assume that is on the EU mpg test cycle. I am assuming though that they do mean US gallons and not Imperial gallons.

Anyone know how that translates into the US mpg cycle? The best I can figue is that would be edging near 100 mpg US cycle but I’d love somebody with a better grasp to tell me if I am close.

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**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\
**Post date:** [October 12, 2014, 3:53pm UTC](https://boards.straightdope.com/t/eu-to-us-mpg-conversion-air-hybrid/701107/2 "2014-10-12T15:53:58Z")

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can’t really compare w/o actually testing the car to the EPA drive cycles. As a point in comparison, the UK market Prius is listed as achieving 72 mpg vs. 51 for the US market car. The differences in US vs Imperial gallons isn’t enough to account for that much of a difference. as far as I can remember the EU drive cycle is rather “generous” compared to the 2008+ EPA test.

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**Author:** ![Baracus](https://avatars.discourse-cdn.com/v4/letter/b/2bfe46/32.png) [@Baracus](https://boards.straightdope.com/u/Baracus)\
**Post date:** [October 12, 2014, 4:05pm UTC](https://boards.straightdope.com/t/eu-to-us-mpg-conversion-air-hybrid/701107/3 "2014-10-12T16:05:09Z")

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If you convert the 2L/100km figure also given in the link to miles per US gallons, you indeed get 118 mpg. That isn’t what this car gets yet though. Per the article:

> [@](#):
>
> The automaker’s driving force (ahem) behind the HYbrid Air is to provide an affordable car that meets the government’s goal of 2.0 l/100 km (118 mpg US) **by 2020**.

If you follow [this link](http://green.autoblog.com/2013/11/02/peugeot-208-with-hybrid-air-technology-headed-to-production/) in that article, it appears that the compressed air hybrid is rated to acheive 97 mpg.

As for what that translates into in US cycle terms, as **jz78817** said, you would probably need to actually run it.

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**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\
**Post date:** [February 26, 2015, 4:09am UTC](https://boards.straightdope.com/t/eu-to-us-mpg-conversion-air-hybrid/701107/4 "2015-02-26T04:09:47Z")

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[Belated update](http://blog.caranddriver.com/deflated-peugeot-citroen-shelves-its-air-hybrid-technology/) - it won’t get any mpg.

> [@](#):
>
> PSA Peugeot Citroen has put an indefinite hold on the development of its promising-sounding Hybrid Air powertrain, apparently because the company has been unable to find a development partner willing to split the huge costs of engineering the system. …