Equivalent MPG of cycling - garage feature?
 

The plan from the start has been to add a Garage feature for cyclists. There are 2 approaches we could take (or both, I guess)

• A simple comparison, showing the proportion of biking vs. driving

• Peakster suggested factoring bike (or any hpv) distance travelled in a way that gives "combined" MPG with your car(s). EG. if you got 40 MPG last month in your car, and covered 100 miles, but you also rode 100 miles commuting by bike, your total transportation FE for the month is 80 MPG.

• Another approach is if your bike computer calculates/estimates energy output, you could just do the math and figure out equivalent FE like I did with the ForkenSwift "MPGe".

How do you figure MPGe for a bike, someone helpfully asks?

The MPGe formula would simply be distance (mi) / gallons equivalent.

Here's a conversion site that will give you the US gallon equivalent of gasoline in kJ (and lots of other conversions): http://www.onlineconversion.com/energy.htm

1 kilojoule = 0.000,007,589,6 gallon [U.S.] of automotive gasoline

So if you rode 100 miles and the computer said you used 11,300 kJ then your MPGe is...

100 miles/ (11,300 kJ * 0.000,007,589,6 kJ/gal)

or 100 miles / 0.08576248 GALe

= 1166 MPGe

PS - anybody want to check my math? :p

Also, I just kind of picked the kJ figure for going 100 mi. out of a hat, based on one reference I saw after a quick google. It could be wrong.

How many people actually have meters that calculate wattage though? Powertap!

And how accurate can they be? What do they measure - heart rate? Body temp?

Very nice. I don't know how many will have the computers that will figure kJ so it would probably just be best to use some form of the combine FE. I'm trying to picture how that would work. I guess you would have another column in the garage that has transportation index? Would it be on the rolling 90 day average also?

I like the combined FE idea too.

I figured it would just be for the year. That would be easiest, to start.

It makes for another cool top 10 list, plus it would show in your individual garage.

Some are pretty accurate. Here's the poop.

Powertap actually calculates energy output, that's why they cost 1000 USD and not many people have them, :p

Thats what I was thinking too. I would like to have a month by month bike mileage chart like this:

http://www.bike-pgh.org/resources/submit-your-miles

Route slip has a nice graph based on week to week mileage (it also shows the amount of climbing too, based off of google maps):

http://a81.ac-images.myspacecdn.com/...9f39dd9b00.gif


If you want to put a more environmental spin on the graph. You could say total mileage by bicycle X,XXXmiles = XX.X gallons saved = X,XXX lbs of CO2 saved.

It's easy to forget how intense cyclists can be until you read something like that. Then again, I'm sure they'd say the same thing about FE nuts after seeing someone who posted a inverview with the inventor of the ScanGauge.

The problem IMO is that doesn't illustrate fossil fuel consumption, which depends heavily on diet. We all know that oil extraction/refining eff=~80-85%, but the fossil fuel equivalent we use when cycling depends, more than anything else, on diet.

You're right about the energy to produce food and that riding a bicycle does not mean that you are using no fuel but the average american eats 3700 calories a day. The average bike commute is 10 miles round trip. This is not going to change the amount of food eaten then normal (IMO). From my experience my diet became much better when I started to ride and I was eating less meat which is the real energy killer.

That's a slippery slope yer on IMO. Whether or not people overeat is immaterial to how much fossil fuel equivalent they use if they bike, which depends on their diet. We could just as easily say that we're gonna burn "X" amount of gasoline anyway, so there's no point in driving more fuel efficient cars. IMO we should look at the well to wheels, so to speak, eff for any fuel source. Also, meat may not be too bad depending on where it came from. I mean, it's no potato, but it's also not lettuce. :thumbup:

I think this is the best way to go, there are just too many variables with the other way.

I think it would be cool to have the "cyclelog" and gaslog kinda combined. By this I mean that when you add a new gaslog entry, have a prompt for updating mileage for your cyclelog(s)

http://i239.photobucket.com/albums/f...er/fuellog.jpg

Then, compare miles driven (on that tank) with miles biked during that same time period. You can compare as a percentage and then (if we get all fancy) graph it over time.

Do those computers tell you how much energy you put through the crank - or how much energy you expend.... I trained/fit cyclist is about 25% efficient (according to the research I've done for the HPV competition/design reports) - so if those power meters don't compensate for that... you'll have to multiply by at least a factor of 4...

AND, where you get your food.... Lets say, perhaps hypothetically, I practice freeganism and get a sizable portion of my food from - a dumpster, for instance... How does that equate into the grand scheme of things?


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I second (or third or whatever) the motion do do a comparison/ratio of cycling to driving... Perhaps have a gallons displaced based on the FE at the time of miles on bike? Of course, my commuting will be a bit more efficient compared to most of the rest of you - no hills and very very small grades :D

I'd just like to an incentive for using bikes on this site, and I think a separate "total" MPG box for all vehicles in our garage would be very enlightening to members here.

Nice graphic, Andrew.

I was talking this over with Ben, and we decided a bike log will be the next addition to the garage, following the Trip Log (which is in the works and just about ready).

Peakster: I kind of chucked at the notion that you might need a website tool to give you an incentive to ride more... Maybe I'm reading more from your comment than you meant. Because... I'm like that: sometimes a little incentive finally gets me to do something when the "big" incentive couldn't get me going in the first place.

Anyway... I'll post back to this thread with progress updates on the cycle log when I get going on it.

Time to get that triplog active, darin! :)

I think the main thing we need to remember going forward with some sort of cyclog is that whatever we choose to do the calculations we will inevitably be in odds to someone else doing them, so we shouldn't necessarily freak out with it, but rather try to do a good job and be transparent about how the equivalents are calculated.

It's essentially the same as getting oil from restaurants for bio-diesel. A great initiative, but not scalable.:D

I would say that if you can honestly and truly say that your fuel is going to be wasted anyway, then sure, why bother? But for that to be the case IMO you would need to go the extra mile and advertise the food for free on CL or something, and have no place to donate it to, for it to be "free" energy. I take this same approach wrt WVO/etc FWIW... :thumbup:

Oh no... This, hypothetical, group of dippers comes with a sort of code (as hypothetically explained to me). Don't advertise to the masses - but always ask fellow dippers where good locations are (while dipping, of course) :p

Newton's comment on scalability applies here... It's not scalable, nor should it be. Lucky for us (ermm... them), not to many people are willing to eat food that came from a dumpster :p Waste oil is a totally different scenario - as you don't have to be queasy about it's past life as a salable product :p

I think we need some sort of, say, scale, to determine whether something is scalable or not, que no? :turtle: