Comments on: Save $550 a Year by Hypermiling

By: Eco Friendly Cleaning

Eco Friendly Cleaning — Fri, 07 Aug 2009 11:06:19 +0000

Eco Empress Green Living Carnival – August 7, 2009…

Welcome to the August 7, 2009 edition of eco empress green living carnival.

Gabe Swinney presents How to Buy Baby Clothes posted at Organic Baby Wearhouse.
Eco Fashion

Amir Marzouq presents Checking out Eco-friendly Plus Size Fashi…

By: The Best of the Best in Money and Personal Finance #5

The Best of the Best in Money and Personal Finance #5 — Sun, 02 Aug 2009 18:57:58 +0000

[...] presents Save $550 a Year by Hypermiling, posted at Frugally Green, saying, “If you want to green your life and save money doing it, [...]

By: Green Holidays Summer Carnival - 2009

Green Holidays Summer Carnival - 2009 — Thu, 23 Jul 2009 14:07:25 +0000

[...] just around town is covered by Tyler, who explains his new concept of using the car! Take a peak at Save $550 a Year by Hypermiling and see what you think [...]

By: Tyler

Tyler — Thu, 23 Jul 2009 05:31:31 +0000

Dren,

You certainly make a convincing argument. Since I have honed most of my hypermiling techniques now and I have a fairly consistent driving schedule, I am going to use the next couple of tanks of gas to test your argument on my own vehicle. Follow me on Fuelly and lets see what happens. I’m very curious.

By: Dren

Dren — Wed, 22 Jul 2009 17:38:42 +0000

Tyler, slow acceleration is even more harmful than I thought. My private guess was engine fuel efficiency peaks at 2/3 of max engine power, while Wikipedia gives a reasonable 75% (wikipedia.org/wiki/Engine_efficiency).

Regarding relative power used during acceleration, feel free to make your own reasonable estimates. Estimating 25-50% of max hp used for “NORMAL” (not jackrabbit) acceleration, and 15-25% of max hp for SLOW acceleration, we see that *even_normal* acceleration under-utilizes the peak engine efficiency of 67-75% (or even higher, since Wikipedia gives a mid-point estimate). Slow acceleration, because it utilizes way, way below peak engine efficiency, is thus extremely wasteful of fuel.
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Fortunately, little actual time is spent accelerating that so that the loss is masked by the authentic gains of other actions taken.

By: Tyler

Tyler — Sun, 19 Jul 2009 19:03:32 +0000

Dren,

After reading around some more, it looks like it depends on how old your car is (carbureted vs fuel injected, style of transmission (auto vs. manual), as well as the brand of the vehicle (different manufacturers tuning their engines differently).

I see a lot of arguments on both sides of the isle. From experience, I can say that accelerating slowly improved my mileage, but I have no way to prove it.

Perhaps the best option for most people not interested in experimenting would be to just accelerate normally.

By: Dren

Dren — Sun, 19 Jul 2009 17:42:10 +0000

Good article.

I only question that slow acceleration should be #2 in fuel savings.
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It sounds attractive, but car engines are most efficient in their middle or upper middle range of power, and today’s cars have strong power to weight ratios. That means that at gentle, slow acceleration from a start, today’s cars are using their engine’s inefficient lower power range.
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Note that air resistance is NOT an issue here. Not related. Also, the slower you accelerate, the more time is taken in the acceleration phase, so you are spending more time in that inefficient regime of your engine.

By: Tyler

Tyler — Thu, 16 Jul 2009 16:02:40 +0000

Anne –

Maximizing the usefulness of our trips is probably the most important thing we can do. No matter what hypermiling tricks you employ, you always save more gas making 1 trip instead of 2, right? Thanks for the insight.

By: Anne O

Anne O — Thu, 16 Jul 2009 02:22:42 +0000

I’m excited that I have regularly incorporated all of these! Having a manual transmission helps too. A few other things I do to save: plan all errands for one (as much as is feasible), and mentally plan a route that requires the least back & forth. Also, it’s easy to get used to driving to the same places the same way out of habit, so I try different routes sometimes to see which is more efficient.

By: Cash in on the Cash for Clunkers Program » Frugally Green

Cash in on the Cash for Clunkers Program » Frugally Green — Wed, 15 Jul 2009 12:05:43 +0000

[...] but I’m afraid it likely won’t last too much longer. I’ve implemented all the hypermiling tricks I can, but I still worry that it might be on its way out. With dollar signs in my eyes, [...]