100+ hypermiling / ecodriving tips & tactics
 

100+ hypermiling / ecodriving tips & tactics

Feel free to use this thread to make suggestions or post additional tips.

It's a work in progress, of course, as is most of our driving.

That's a good idea and sound like a thread for all it own. Of course that would be subjective but My numbero uno would be instantaneous FE feedback:turtle:

I think you touched on it with number 58 (Push it 1), but an addendum could be never get yourself into a space you'll have to reverse out of when parking in public spaces.

Really really good stuff. :thumbup: :thumbup:

I call this 'pre-braking', or braking early to save momentum. It's not really about braking hard, it's about braking early. Don't want people to slam on their brakes for seemingly no reason. I would also say this is for stop/slow looking far ahead

'It may permits'?
Minor nit: What we're looking for is the balance between shortest path and highest exit speed. For many curves we want to cut the inside corner, not go the long way around, in order to decrease distance traveled.
A true racing line is one where the entry speed is high and where you can get back on the loud pedal earliest. :p

I guess I didn't explain it well. I meant to convey it's the type of braking I do when you've mis-timed a stop/slowdown or you're presented with one that was impossible to predict and you want to salvage what you can in the remaining (short) space. It's reactionary rather than anticipatory. (And I do mention the safety consideration of braking sharply.)

Thanks. I'm sure that's not the only typo/brain fart in the list.

Good points. I did qualify it with "generally" :) Anyone who knows a bit about actual racing may take issue with the oversimplification in that tip. (Strictly speaking, the racing line isn't always the largest radius.)

Good point - that's actually covered in "Parking tactics: reverse in"

But I expanded it slightly from your prod.

What would be on your top-10 for the average motorist (who will probably never really go into the "advanced" stuff).

I agree with Laz's first one: instrumentation.

I'd add: reduce highway cruising speed as a no-brainer with a big payback. For the "average" motorist I might condense the momentum conservation tips into "why are you still accelerating towards that red light?" :)

True, though the list isn't really meant for the general public. The general public can continue to get their tips from the occasional newspaper or TV item. If you're on this site, you've already demonstrated you're not average (to put it carefully).

Great list!

The "Average" motorist is not going to invest in extra instrumentation for economy. He may be persuaded to use the on-board stuff.(I've talked two of my co-workers into this, the price of SG turns them off, ie "Do you know how much gas I can get for $170"?)

I would like you to make a printer friendly page for it.
I will print it and put it up in the employee lounge.
If that's not an option for us I will see if I can cut and paste to MS Word and go from there.

I hadn't considered half drive half bike before, good suggestion.
I will have to see where I can park and ride, then I must go buy a bicycle. Everything in time, one step at a time.

Darin and Ben,
Thank You for all you do, I am sure this is your second or third full time job.
Schultz.

I'm really missing the point of this one.

61) Parking tactics: orbit to bleed momentum

If you find you have too much momentum after reaching your preferred parking spot, continue coasting further down the row or "orbiting" a spot until you can roll to a stop in position without touching the brakes. (Depending on traffic in the lot, obviously.)

Seems like a no brainer, but if this list is intended to be distributed amongst unlike minded individuals...
"Never idle!"
This is quite possibly the most annoying habit I see, I'll be walking to class and walk by 10s of cars that are just sitting there running so the owner can use the radio or a/c. Worse yet it's generally always a girl just putting on make up while the car is left running. Saw this yesterday with a lifted Hummer H2, almost lost it. haha.

Nice, detailed list. It's nice to see it all in one place.

I have a comment regarding #86 and #89, referring to the A/C.

In my experience, the average person thinks the A/C has to be on max blower and max cold. Under those conditions, it's adding maximum load.

I typically turn on the A/C once I'm cruising, not while starting out or in tight traffic. Once it cools down enough to be effective, I adjust down the temp to a more moderate level, something less than max cold.

At highway speeds, my A/C can create frost bite. So, I back it down and while it will still run, it will run less often but still provide cooling - much like your manual cycling, but more "hands free."

OR
 

just drive a metro that doesnt have AC....its gonna be hot this summer.:turtle:

A local church had a save at the pump day where gas was a $1.00 off the posted price. As expected a large crowd showed up. It was reported that there were people that waited in line for over an hour and a half. Now on a 85 degree day how many people do you suppose were sitting there with the car and AC off for the time they waited.

I'll see what I can throw together.

Thanks to the mods, too! That tip you liked was actually put in by Laz. :)

It's essentially damage control. If you've still got some momentum when you get to where you were going to park, don't brake & waste the momentum to park in that exact spot. If you have the option of rolling into a different space, keep coasting until you can pull through just as you stop.

It's orbiting because you may end up circling around your intended spot a little.

Functionally it adds nothing to your trip, but it will help the MPG numbers slightly.

I'm with him ... if you reach a parking space with to much momentum keep circling? Screw it just park ... I would think, the time wasted idling while you coast is more than the time it takes to brake and shut your car right?

Or if you coast with engine off, then why dos it matter, brake and park ...

Or did I miss some point here ?

If you're coasting engine off, doing anything other than rolling to a stop will lower your potential fuel economy. Yes, we're talking about tiny differences.

If you're idling and moving at a low speed, then yes, you should just go ahead and park.

The take-home message is: avoid the brake pedal. Parking is one time you may have the option of rolling to a complete stop because there's no set 'stop line' if you have flexibility on which spot you can choose.

I agree that tip amounts to a numbers game, but I think it has educational value.

Really good list! Everything I can think of is covered.

I know I'm probably an exception here, but I generally fill up at the cheapest place in town (Costco) and now that prices are on the rise they are generally subject to 15 minute or more lines. Anyway, I shut off the engine and wait for all cars in front of me to fill up and then I push my car up to the spot and proceed to fill. :o

You will lose it one day
 

I must confess, Idling is my biggest pet peeve also.
As I walked through the lot at Big Box Mart one day I saw a Hummer idling, Young Lady behind the wheel, A/C on, drivers window down(for cigarette exhaust), and she was on the phone.
I toyed with the idea of asking her about her fuel resources for a moment (this was after gas went >$3 a gallon here), when I heard her complaining into her phone about the price of gas.
I chose to move on.
I left Big Box Mart and as I walked past again she was still complaining about fuel prices.
I laughed so hard I dropped my stuff.
There are people in this world who are not going to change, they will make you laugh, cry and wonder why we are not allowed to kill our young.
S.

Wow. Yikes!!

I think you should submit that to Webster's as an updated definition of "irony" (among a few other words I can think of :)).

Metro,
I was probly in the store for 20 - 30 min.
She has to have burned 1/2 gallon of gas.
I laughed so hard I dropped my bags and told everyone that would listen when I got to work.
Originally I wanted to ask her if she owned a gas station, but when I overheard her conversation I couldn't bring myself to do it.
Irony, Stupidity, call it what you will, it was still unnecessarily wasteful.
In retrospect, after hearing her complaint I should have told her it was her fault gas is so high.
But that would only have enraged her and then I would get shot.
too bad, so sad, ur dad,
S.

I had not thought about backing into spots. Sometimes when i get to work later than usual, the good Pull out spots are taken and i had wondered what the best alternate was. Now i know - back into a spot with a warm engine to allow pull out with a cold engine.

as for the young lady in the Hummer.
Irony just does not seem strong enough..
like the commedian who has the "Here's your sign" bit..

Steve

Reversing in has the added advantage of being generally safer, too. And the reason (better visibility when leaving the spot) is yet another contributor to better efficiency: if you can see, you can wait to start up and just go when it's clear, rather than creeping slowly out in reverse until you have a good view & an opening. (Assuming vehicles on either side creating visibility issues.)

Of course it's one of those miniscule differences. But the pennies do stack up.

#54 - EOC

I would change it to "turn the key to ACC long enough for then engine to stop running, then return the key to Run." That's much safer, and you'll actually be counting the miles traveled.

Good point - edited. I have a kill switch on my car - the key always stays in "Run". Thus my oversight.

These are my money makers
 

18, 23, 26, 31, 41 and 44 are the real money makers for me.

I use 44 as my guiding rule. In todays effort home 24.9 miles (49.5mpg) I did not stop once!

But... unless you can get closer to where you'll be headed when you leave, it does no good.

That's something I've noticed in the short time I've frequented this site and forum. There are tips that recommend, for example, taking a longer route with less stops. That may or may not help - the goal is (or at least is in my case) minimization of fuel consumption consistent with the life one has chosen to live. That's not necessarily the same as maximizing the indicated or calculated m.p.g. For example, if you can get to work by driving a route with stops and it's 15 miles at 30 m.p.g., you'll use 0.5 gallons. If you substitute a route that's 20 miles with less stops and you can get 35 m.p.g., you'll burn 0.57 gallons, or 14% more fuel. This, to me, is the opposite of the way an ecomodder should think.

My $.02...

In my case, I can drive 10 miles, 10.6 miles, or 11.3 miles. After a year of testing, they all consume the same fuel. So I take the 11.3-mile route. If the shorter one used less, I would go that way. You have to test it and make your own decisions.

Agreed, PA32R and PaleMelanesian. The issue of route selection for minimum fuel consumption vs. max mpg is touched on in "take the road less traveled".

Have to accept also that some people treat MPG as a sport where the number is more important than the total fuel use, and vice versa. Everyone has different motivations.

New Tip
 

Found one that isn't on the list!

Always fill up at the same station - And no, it's not a numbers game. Has to do with the fuel trim tables in most cars (visible through SGIIx). When you change brands of gas it can cause your trim tables to go through a bit of re-programming. This can have a small (or large) hit on MPG. The idea is to reduce the variance in the fuel going through your engine as much as possible. Using the same brand gets you most of the way there, but filling at the same station cinches the deal. Certain metro areas (like Houston) require special blends of gas. If someone was to fill up at a shell in Bryan, TX they would get totally different gas than filling up at a shell in Houston. Sticking to the same station (and same pump if your wacky) reduces the probability of variance in your fuel mixture as much as possible, hence mitigating the reprogramming of trim tables to a minimum. As a side note I'd say that high dollar brand names are more consistent than bargain gas. One other bonus with using the same station is that you might actually get lucky and hit the same batch in two consecutive tanks. The station has huge underground tanks. If you fill on Monday and Friday (pick any two days) you might actually catch them before they get their next shipment of gas. Also when they add a batch, that change is blended throughout the whole station's reservoir, reducing the change per gallon. On the "numbers game" side, using the same pump will reduce the variance from tank to tank since each pump is calibrated independently.

I've been doing this since November and it has a HUGE impact on my Ford. Not so much on my Toyota. I'd say changing stations reduces my tank numbers by 15% no the Mercury. Takes about 3 tanks for the trim tables to settle down and ease back in to the consistent 30+ range.

If I can only give 3 tips to someone it's:
1) Tire maintenance (air, rotation, balance, align). <= On the list.
2) Drive your car like you'd ride a bike. <= On the list.
3) Always fill from the same brand, station, and pump.

Nice... Try finding the station that is consistently cheapest (or in the bottom 3). Pick a pump there and commit to filling your next 5 tanks there. Make sure to try this the month AFTER they switch to the Summer gas. You should see an improvement and save money over the long haul.

I've never interpreted "face-out parking" as backing into a slot if it means you need to burn gas to do it. What you do is find a slot on a hill. Then you coast (engine off) up the hill just past (10 feet) the slot. Then like a pendulum, you'll stop and start rolling back. Cut the wheel and your face-out parked on the top of a hill. Perfect. Only really makes sense if you can do it while in an engine-off coast using the kinetic energy you already have invested in your mass (car).

PS... Absolutely fantastic list :thumbup: Don't change a thing... Well other than my suggestion and the "printable version" thing ;)

11011011

Opps. Found another one two, although some get pretty touchy on this one being just plain nutty.

Fill up with cold gas - Most non-gaseous liquids have very little thermal expansion. But.... petrol has more thermal expansion than say... water. It's not much, but it is some. So the theory goes, if you pump 25 gallons of gas at 6pm (when the sun has been beating on the station all day) the petrol you pump will be a few degrees hotter than if you fill at say 4am in the morning. The petrol expands when its hot so 25 gallons of cold gas may equal 25.001 gallons of hot gas. If theres a chemist out there they can give better figures. Perhaps it's 25.000g vs 25.100g. 12 oz of gas is a lot to me ;).

11011011

Thanks, Dan - I'll add it. I presume the effect could go the either way though: if you happen to switch to a fuel brand with a lower energy density (from a previous high energy density fill), you'll have "lean burn" advantage until the O2 sensor finishes adjusting the fuel trim. ;)

I wonder about the cold gas tip though. Not questioning the physics, of course. But is it more of an economics issue than an efficiency issue? The difficulty is how do you choose to buy cold fuel vs. warm? (My reading on the lateday vs. early morning fill timing is that underground tanks are mostly unaffected by atmosperic temp fluctuations.)

I love these tips that split hairs. Their impact may be somewhere between nil and tiny, but the fact that people are interested enough to consider them is very, very cool!

They're also the kinds of tips that cause those who are anti-hypermiling inclined to yell and pull out their hair. :)

Very Cool. The digg count is going through the roof on your tip list. My google alerts on hypermiling is getting hyper too. Great job!

Your right on target. The "tip" doesn't reduce your tail pipe emissions, but it does reduce the amount of money you spend on gas each month. Think of it as cold gas costing less than warm gas. The tip can be summarized into Always fill up in the morning, never in the afternoon. Now as far as "what is the temp delta in an underground tank", depends. In Houston, the tanks aren't really underground, but rather in-ground. Think of a back yard swimming pool with a tarp over it. That tarp is made of concrete and has pumps on it. Drill 6 inches through the concrete and your in the stations storage tank. So yes, sun hitting the concrete all day will heat the "roof" of the stations storage tanks, and through convection, the gas itself.

The brainchild of this tip was a law passed in Canada (I believe) a while ago. Basically gas trucks were getting short changed in the winter. They'd fill their trucks to make their deliveries. They would fill 9000 gallons at the distribution center, but only sell 8950 gallons returning the truck bone dry. What was happening was that the gas would cool during the deliveries. So the solution was that tankers sell by the pound. Consumers buy by the gallon. Doesn't matter if the gas in a 9000 gallon (sealed) tanker is warm or cold. It's weight never changes. The fact that the tanker drivers had to push this law through got us thinking that it must be a big enough volume change to warrant all that effort.

Here's a source (the state of Utah): http://geology.utah.gov/sep/energy_e...leage_tips.htm

Google keyword list {gas density morning}: http://www.google.com/search?q=gas%20density%20morning

Here's a counter-source that claims that all US pumps use temperature compensating volumetric flow meters.
I can't confirm this claim: http://www.omega.com/techref/flowmetertutorial.html

11011011

the point of orbit is the highest mpg, not the least fuel used. or in laymens terms. cuting off your nose to spite your face.

Orbit can be used productively. One example would be timing your exit so your lane is clear. Without the orbit, you have to take a hard stop killing (and regaining) all your velocity. With a well timed orbit you can exit the parking lot with about 50% of the velocity you started your orbit with. I've done this (maybe twice) in the last year or so. Nice to have in the grab bag for the one time in a blue moon that you could use it.

DISCLAIMER: The obvious stuff about not orbiting in a crowded parking lot and not around people trying to cross all applies of course. People come first... MPG comes 42nd.

11011011

I was talking about not parking till your done coasting, even if the spot you want is open. then maybe even coming back around and parking in that same spot. I cant even figure out what timing your exit is talking about. Sounds like your talking about leaving the parking lot, not parking. It does sound good though. Make sure your lane is empty before you exit your parking spot.

I really enjoyed the list! Awesome job. Especially 12.

Ideas for consideration...

-Use lighter weight oil.
-Make aerodynamic modifications. You touched on this with the roof rack removal tip, but there are lots of easy and effective mods.

Also, I feel like #14 needs some qualification. I haven't tested, but my guess would be that IRL the cons would outweigh the pros.