Average power consumption

Your average W/Hr per mile (not kilometer)

  • >10

    Votes: 7 11.7%
  • 11 - 15

    Votes: 8 13.3%
  • 16 - 20

    Votes: 15 25.0%
  • 21 - 25

    Votes: 11 18.3%
  • 26 - 30

    Votes: 9 15.0%
  • 31 - 40

    Votes: 5 8.3%
  • 41 - 50

    Votes: 1 1.7%
  • >51

    Votes: 4 6.7%

  • Total voters
    60
It was sunny so I hooked up the Watts up meter for my trip to the grocery store and back.Me,bike&rear hub motor ~200lbs.

I rode 7.279km and used 81.7wh's = 11.22wh/km which is
17.95wh/m.

Could have been a bit better average wise.It's really hot here today and didn't quite pedal as much as I usually do.

Eric
 
I just finally hooked my WattMeter to my trike but I usually do calcs based on the one in my Astroflight 112D charger. Been averaging 25-30 Wh/hrs/mi :) Sorry metric fans! Trike and me weigh over 300 lbs or 136 kilos or 12.5 stone or whatever. Seriously, in the medical field we standardized to metric quite a while ago, yet laceration and scar length are still usually measured in inches. In the pharmacy, most of the old die-hards have died taking with them drams, grains and all them other avrodupios and troy weight funnies!
 
At 24V, I seemed to average about 11WH/mi., at 36V, I averaged 15-17 WH/mi and now short-distance trips at 48V seem to consume about 25 Wh/mi. On longer-distance trips, I tend to ride conservatively since my battery capacity is more limited than I originally suspected.
 
The astute amongst you will have noticed that my avatar changed at the beginning of this month. That's because I aquired a Kalkhoff Pro Connect commercial pedelec bike. I still hope eventually to convert my Trice T recumbent trike to electric power, but for now, having been put off adding a powerful (and illegal) motor to the trike, I decided to get something off the shelf. The UK (and EU) power limit for trikes is 250 watts and in my opinion this is too low. The US limit of 750 watts would allow non-enthusiasts to get the assistance that they need to adopt ebikes for commuting to work - 250 watts is not enough. Having been passed by 4 police cars in one ride (in a very rural backwater) I'm not risking my car driving licence to advance the cause of ebiking!
I much prefer the safer, lower ride position of a trike. On my second day out on the new bike, I crashed trying to mount a half-inch high kerb to get out of the way of a persuing lorry; it was wet. No great damage fortuneatly, but it goes to show that the lower position of a trike is much safer from the "falling off" point of view.
Here is a little spreadsheet showing my first few rides and some data to do with power consumption. You will notice that the last column is WattHours per mile divided by Total Ascent - intended to be a crude measure of battery performance relative to the climbing task involved. If you can suggest a more sensible formula I would be grateful.
View attachment BikeTrips.ods
View attachment BikeTrips.xls
 
Wife and I currently burn 9 watt-hour/mile (average) with no wind/tail wind on our tandem. We are able to maintain 22mph with 300 watts (58 volt system) of juice applied and moderate to heavy pedal. I have been recording data from the CA since we got our system setup. E-bikes rock!
 
I was able to go 40 miles (still had juice left, how much I do not know) with a 24V 20AH Ping pack. The terrain was mostly flat, one very steep 1/4 mile long hill. This was on a Giant Lafree pedal assist bike, average speed was probably around 15MPH. That is 12 WPM.

Deron.
 
my Wh/mile rating is very variable, with riding style the biggest determining factor and terrain a close second.

picture1buu.png


that last data point isn't in error. below can be found my discussion of it. most of the other 25-35 Wh/mile data points are from my daily commutes to and from the hospital. on these commutes i pedal but not overly briskly, and i'm either stopped at a light or full throttle. my goal on the commute is to minimize time, not energy usage, as the commute is far under the capacity of my pack, which is recharged daily.

Toshi said:
i altered my riding style from my youthful, aggressive, all-out war on cars normal stance to the lines of "cruise along at 14-20 mph while pedaling briskly". in other words, i went from riding like a 27 year old to riding more akin to a 72 year old. this change in riding style greatly affected energy usage. while still averaging 14.5 mph including time spent at stoplights, etc., i managed to halve my normal Wh/mile figure.

stats for this ride:
16.99 miles
6.01 Ah
16.2 Wh/mile

thanks to this more "conventional bike"-type style, i got a good workout out of it, too. however, it wasn't a wash as compared to the road bike: i pedaled less rigorously than on a road bike, i carried around some weighty cargo in my panniers, and i averaged a higher speed than i would have on a road bike to boot—it's a hilly route and i'd expect to average 10-11 mph from past experience on similar routes. score one for the e-bike.
 
nomad85 said:
I dont know/care about the watt hour per mile, isnt Ah per mile more important? I get about 4 miles per Ah at 20mph or 2 miles per Ah at 30mph.

Sorry to dig up a semi old thread, but...

4 Miles/Ah @ 20MPH? Good lord, on what system? 40 miles on a 10Ah pack @ 20MPH... probably the best #'s I've seen yet. I'd love to duplicate that setup.
 
Dan K said:
nomad85 said:
I dont know/care about the watt hour per mile, isnt Ah per mile more important? I get about 4 miles per Ah at 20mph or 2 miles per Ah at 30mph.

Sorry to dig up a semi old thread, but...

4 Miles/Ah @ 20MPH? Good lord, on what system? 40 miles on a 10Ah pack @ 20MPH... probably the best #'s I've seen yet. I'd love to duplicate that setup.

It is doable. I do this daily on my commute 20 miles round trip, flat route. I budget 1 to 1.5 Ah for 7 miles with an average speed of 20 MPH, with short burst to 32 mph. I have 6Ah (3 Bosch fatpacks) for a light setup. Of course this is with pedaling, but the trick is to pedal at a high cadence (>90 rpm) to generate power and using the motor to maintain speed. My bike is light for an e-bike; hardtail small frame MTB equipped with road cranks and a lightweight, low torque, high speed, direct drive motor (BMC 1000W).
The bike weights in the 40's, so I can pedal this on human power alone at 16 to 17 mph.
 

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eZee front, 36V/20Ah Ping. Average current draw 10A or a bit less, no pedaling, it's a 20mph bike because of various considerations
of battery conservation, safety, efficiency. Remember: I am not pedal assiting at 20 per for that so-so efficiency number.
Cycle analyst: 20Wh/mile. Very low pressure, fat Bontrager slicks on a 65 pound all-steel basic cruiser bike, level terrain.

OEM eZee 20A controller. Runs cool. Dunkable as a doughnut, totally waterproof forever
and as tough as a steel nail unless hit with a hammer off kilter.
 
This summer so far I'm averaging 52wh/mi... what's that like 32.3wh/km? That's about 40-60wh more in total than last summer with a 4011, but the 504 is much better at sustained hill climbing and I have to do way less pedaling and go 5-6mph faster. Win-win. This morning I was a little late to work so dumped 3kw into the 504 for about 8min straight (a little under 3 miles) and nothing was even warm at the top and I was going up 9-10% grade around 22mph. Liking this motor. :wink:
 
pwbset said:
This summer so far I'm averaging 52wh/mi... what's that like 32.3wh/km? That's about 40-60wh more in total than last summer with a 4011, but the 504 is much better at sustained hill climbing and I have to do way less pedaling and go 5-6mph faster. Win-win. This morning I was a little late to work so dumped 3kw into the 504 for about 8min straight (a little under 3 miles) and nothing was even warm at the top and I was going up 9-10% grade around 22mph. Liking this motor. :wink:

"Liking this motor", and this coming from a guy who started a thread called "I don't like hub motors". Once you have a real motor and a real battery pack, then hub motors rule.

Regarding the topic, it's really kind of pointless. At one end of the spectrum you've got the little cyclist guys who got tired of working so hard on hills or getting sweaty on their way to work, so they still pedal their asses off or ride slow with their meager battery packs trying to stretch them as far as possible. At the other end of the spectrum you've got the performance guys, who even if they don't weigh much, eg Doc Bass, accelerating hard or going fast still chews up the juice.

The topic is well intentioned but the results really are meaningless. The only meaningful number would be a real world comparison of different motors riding the same route, on the same bike, in the same the wind conditions, and pushing the same size and mass with zero pedaling.

Take me as an example: I run somewhere between 40 and 50 wh/mi on average (more if I'm tackling significant hills). That sounds like my bike isn't very efficient unless you consider that if I try I can do better than 20wh/mi, and that's with a 115lb bike and I'm a hard to accelerate wind blocking 240+lbs. Don't forget I run a moderately knobby motorcycle tire on the back that's road worthy enough to be silent on pavement, but probably not too efficient. My typical riding is pedal assist at the start through the first 15-20 meters while I can still keep up, accelerating to 35-40mph before some dickhead in a gasser slows me down for whatever reason, OR I accelerate to about 30mph with no pedal assist due to a kid on the seat in front of me and a kid in back of me going to or from school. The no pedal assist during acceleration offsets pretty evenly since I back off of the throttle much sooner with the kids aboard, because I don't like going too fast with them. When it's just me my average gets inflated by the occasions when I know I have good flat road for a mile or more, and I'm in the mood for an aerodynamic tuck with WOT trying to beat my maximum speed for that charge according to my bike computer. Typical riding though is more relaxed and less than WOT, while still getting up around 40mph, instead of trying to break my 55mph record for flat road. No matter what I don't care about wh per mile, since even at 50wh/mile my current pack will get me 50 miles and I only ride 10-20 miles a day. If I want to take a leisurely ride and slow down to 20mph without the stop and go of running errands, I can easily go more than 100 miles without a recharge, unless I have to go over a mountain.

I go a step further than the guy only worried about ah/mile. All I care about is what is my pack voltage. Unfortunately it requires some experience with your pack to know the true halfway point, because it certainly isn't nominal voltage unless your tactic is no pedal assist down to nominal and pedal as much as possible or slow way down once you get below nominal.
My vote is that nominal voltage be redefined to the voltage point where half of the power is dissipated instead of half of the amp-hours.

John
 
John in CR said:
"Liking this motor", and this coming from a guy who started a thread called "I don't like hub motors". Once you have a real motor and a real battery pack, then hub motors rule.

Uhm... no idea what you're talking about.. I've never started a thread with that title. :?

EDIT: I think I found the thread you're talking about... that was swbluto that started that one.. :?

http://endless-sphere.com/forums/viewtopic.php?f=3&t=9520
 
PBset, sorry about the mixup. If they can just come up with a silent geared hub capable of several KW, which has the durability of a good direct drive hubbie, then we can have our cake and eat it too. I can't wait to go to 2 motors and a higher voltage with mine. My average power consumption may approach 100wh/mi, but what do I care. I've got the batteries and never charge in the middle of day. I think I can afford the few extra pennies, and a large chunk of the electricity here is green. Soon I'll fly my wind turbine and can be as electricity wasteful as I want with zero negative impact on the world. :mrgreen:

John
 
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