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[Devils Advocate]

I have seen a few posts relating to time differential over a distance traveled when dropping from say 70MPH to 60MPH. Most excuse the difference as only being 5 minutes or so.
According to my calculations over a 30 mile trip, that would be a difference of around 5 minutes. 70MPH is 16% faster than 60MPH which would mean your trip would only take 25 minutes at 70MPH. This would seem minimal, but when calculated out over 225 commuting days per year. That amounts to 18.75hours in each direction x 2. Over the course of a year, that's a lot of time.
Over 10 years, that's 375 hours or the equivalent of nearly 48 - 8 hour days. Lets say you make $20/hr. That's $7500 over 10 years. Nothing to sneeze at.

[/Devils Advocate]

Would you actually be paid for those hours? Probably not.

How much is your blood pressure / mental well-being worth? Driving in a calmer manner improves the quality of your time immensely, both during the drive and afterward.

if you want to look at it monetarily, you might calculate the gas savings over the same period. as the costs go higher, you are saving more and more by slowing down.....

I think it depends on many factors:

Is the road clear of other traffic during your 70 mph trip or does it clog in places? Most people don't take into account that they rarely average 70 mph, even if that is the speed they are driving, because of slowing down for other traffic. So does the 60 mph drive end up 3-5 cars behind when they reach the clog, and then they both end up with a nominal time difference?

At the higher speeds, your reduction in MPG due to aerodynamics grows larger with each MPH, so you would also need to consider the difference in your FE. If you went from 40.6 to 45 MPG just by going 60 instead of 70 mph, you would need to add that to your calculations as well.

Another factor is how much less stress you may feel at the end of your 60 mph commute. The 70 mph commuter may take additional time to "decompress" once you arrive at the destination, so who is really more ready to "get to work"?

For me, I found a shorter route that took my commute from 17.2 to 14.0 miles, so I actually arrive sooner or in the same amount of time. The new path is also less congested due to the fact that I'm not on the interstate for all of it and I avoid the traffic jam part of my commute.

So time is definitely money and you have to take into consideration all the factors in your commute, so that you can compare apples to apples.

As PaleMelanesian pointed out, getting home 5 minutes earlier a day isn't going to get you any more pay. If you were in some wierd situation where you were getting paid by the minute and every second you spent on the road was costing you money, then your math works out. By all means, haul ass. For the rest of us that don't get paid by the minute, slowing down by 10 mph saves roughly $200 a year in gas. That's real money saved. A bird in hand is worth more than a thousand hypothetical birds in hypothetical bushes.

You do bring up a good point though. One of my co-workers commutes to the Baltimore area from West Virginia. He would save a lot of money by hypermiling. If he slowed down from 80 though, it would cost him an extra 30 minutes both ways. He gets home late as it is. That would be 30 minutes less to spend with his wife. Hard to put a price on spending time with your family.

According to my calculations over a 30 mile trip, that would be a difference of around 5 minutes. 70MPH is 16% faster than 60MPH which would mean your trip would only take 25 minutes at 70MPH.

25.7 to be exact. That is also a big IF you are referring to a 30 mile, uninterrupted "cruise" segment. Any slowing down due to city speed limits, timing lights, or actual stops at either end will reduce the difference.

Would you actually be paid for those hours? Probably not.

It certainly is a very important consideration in comparing "value."

How much is your blood pressure / mental well-being worth? Driving in a calmer manner improves the quality of your time immensely, both during the drive and afterward.


It's arguably the least stressful (not necessarily the most FE) if you drive within the speed limit, with the cruise control on, and at a speed that minimizes or eliminates closure rates with other vehicles, whether in front or behind you.

If the proposed "time saving speed" involves driving over the PSL, consider the stress increase, $ and time lost if you get pulled over (and more if you have to go to court!) Back when I used to get tickets, I can't ever remember one taking less than 10-15 minutes, and I hear they can cost upwards of $100 these days. :eek: How much is a half day or more off work worth to go to court to beg the judge to reduce the fine to "court supervision, a fine, etc. to keep points off your license to avoid paying higher insurance rates? And all of that is assumes that no damage or injury occurred as a result of the higher speed - not that it ever happens ;)

What I feel is a personally meaningful comparison if no hourly pay is involved is to evaluate the fuel/time/pay savings or increase per year and ask yourself if it is/was worth it to you to spend that much less time with your family...
Hard to put a price on spending time with your family.
Exactly.

Really, it's kind of a silly argument. I lose a lot of time sleeping in a day too. That pesky sleep is keeping me from being productive an extra 6 hours a night! But as has been pointed out in the past, even if you could get from point A to point B by traveling at an average of 60 MPH vs 70 (which is highly unlikely), what's the payoff for the time gained or lost? I have work time, which pays me money. I have family time, which I suppose could be said is an emotional payoff, and then I have my time. This is time that belongs to me, and I can "spend" it any way I'd like. I choose to spend this time by going slower from point A to point B. The payoff is that it saves me not 200 dollars a year, but more like 1000. It also means that I'm not trying jockey for position in the left lane anymore either, so I'm also getting more emotional payback.

Yeah, it's not that simple. There are so many variables. I hardly notice a difference on my commute. I pulse and glide which makes my average speed higher than when I used to drive steady state speed slow in my case. I can't make any extra money by getting home 5-10 minutes earlier but I can make instant money hypermiling. I save easily 50 and more $ a month hypermiling which is 6000 or more$ over that 10 year period. That will pay for the next car or a huge piece of it. If you have a huge commute then the quality of life factors in, but at least drive the speed limit. Most people I talk to about hypermiling are more than happy to reap the big rewards for only maybe a 5 minute difference on a given day for relaxation/safety/money/environmental benefits.

Add into the calculation that you are more likely get into an accident and be more seriously injured at the faster speed. If either of those happen you are going to lose lots of hours that you won't be paid for. Are you willing to spend an extra ten minutes a day driving that may well mean you live an extra 20 years? That gives you a lot more time with your family in the long run.

It's a valid argument, but it's based on the premise that you would do something valuable with those 5 or 10 minutes a day. How much quality time do we really spend with our families each day vs. wasting it on things that are relatively meaningless? Let's say the average american watches a half hour of TV a day (which is WAAAAAAY less than reality). What are the odds that the half hour is something meaningful that will really bring you all together? Not very good if you look at what's on. Yet this is accepted, if not encouraged by our society and nobody puts a dollar value on that.

So if you are going to determine the "worth" of spending a few more minutes in the car, get ready to do the same thing to everything else you do. And be prepared to be surprised what happens.

The other side of it is what happens in "saving" the extra five minutes by driving fast. Is the extra five minutes worth an increase in the odds that I won't make it home in once piece? Not to me, and I've been driving both ways long enough to know which is safer. If I had kids in the car with me, would you rather see me driving quickly to save time or slowly to be safe and simultaneously save some gas? Anything and everything for the kids, right?

Of course there are limits. I'm arguing from the perspective of someone who used to speed and now drives the speed limit, saving more than enough fuel to make me satisfied in my efforts. 5 or 10 minutes a day is about what I "spend" on it, and I really do find it to be less stressful. (Not to mention that it's less stressful on my car, saving more money.) This is the balance that I have found.

plainly put since Hm ing i have saved over $300, i go the same route just a different speed and a different car, however my time is only slowed by about 5 minutes one way, or 10 minutes each day. we get up a little earlier each day, and we get home a little later each day. The time "wasted" commuting each day, has only increased my ability to point out my careless driving techniques before HM ing.

Maybe this should be a poll!

All excellent points. Was just curious what others thought. One other thought though is that when driving 55-65 as I have been doing, I am passed by far more cars that I used to pass myself at 70. Which means that I am encountering more vehicles on my commute. Wouldn't staying with traffic be safer in the long run than having car after car come up and pass you?

Wouldn't staying with traffic be safer in the long run than having car after car come up and pass you?

I see where you are coming from, but it is safer to be passed than to be the passer, because you go through the blind spot of every car that you pass up, and each time has a tiny risk of that car suddenly deciding to go into your lane. This has happened to me before, but I managed to swerve away just in time. :eek: But when other cars are passing you up, they are very likely to see you ahead of them. Also keep in mind that the chance of a fatality occurring during an accident at 70 MPH is substantially higher than an accident at 60 MPH.

PS - This is a great thread you started here! :)

In the long run, letting the speeders flow with the other speeders is much safer for me than flowing with them. During sudden stops, those in the flow usually stop with the flow (braking or otherwise :eek:), while those out of the flow have sufficient time to react and safely avoid the confrontation