System (U, Motor, Controller) Efficiency

[recumbent]

almost all of us pick a 48 volt system ... maybe it's the most ideal power-to-weight ratio, .

1. efficiency: 8-12 wh/km
2. speed: average 20km/h, top-out at 43km/h (16mph average, 30mph max)
3. gradient: mostly flat, with small hills.
4. pedaling: light
5. bike: standard design (for 40 yrs) LWB recumbent
6. motor: #406 Clyte FWD
7. controler: clyte, 48V/35 amp
8. Battery: 48 volt LFEPO4, 10ah's (15cells) not the common 16cell pack.

edit: Changed to Lipo batteries and 9-C motor, as marked below.

[kineticdissent]

Just got a watts up meter installed today. was great to find this thread. my 1 trip #'s are as fallows

efficiency: 33wh/mile
Speed: 20-25 mph avg
Grade: mostly flat, couple downhill grades
Pedaling: just to get started, seems to be easier on the bike
bike: norco mtb w/comfort bike style tires
motor: clyte 5304 rear
controller: clyte 48v 40a
Batt.: 48v sla
other info from my 1st measured ride 47.53 peak amps, 2164 whatts peak, 42.26 min. voltage on a 7.5 mile ride.

[Freddyflatfoot]

1) Efficiency, 8.5-10 Wh/Km
2) Speed, 35 kph cruise, max about 42 kph with pedaling.
3) Gradient, up to 10% for my commute.
4) Pedaling, moderate.
5) Homebuilt tadpole trike
6) bafang rear brushless, geared. 20" wheel.
7) ??? Std, 36v, 14.8 A
Ping LiFePo4, 36v/10AHr

Just checked my WattsUp after my ride home from work last night.
Used a total of 2.5 AHr for my 13.4 k round trip, and 98.5 Whr.
That works out to 7.35 Whr/k!
Just tried a couple of things like using moderate throttle, backing right off when getting to speed and holding it there with pedaling, and coasting down hills, etc.
Still maintained a fairly good speed between 25-30 kph. Wind was fairly light too, which may have helped.
At that usage, I could theoretically get over 50k range!

[Zoot Katz]

1. Efficiency (Watts/mile): Avg. ~8 Wh/km (12.8Wh/mile) I usually get ~100 km out of one charge.
2. Speed (mph | kmh): Avg. ~18 kmh. The bike will do more than 48 kmh on the flats unassisted. I feel safer travelling at speeds motorists expect from a bicycle. My highest speeds (57.4 kmh, 34.4 mph ) are achieved downhill without using the motor.
3. Gradient (%): I climb ~500' in ~2.5 miles. Most of the elevation gain is in the first mile. I live at the bottom of a hill so the last mile homeward can be totally coasted at ~30 kmh if it weren't for the stop signs.
4. Pedalling effort (none, light, heavy, extreme): I like pulling chain and enjoy aerobic activity without going anaerobic. I like to modulate the throttle and change gears so there's always some resistance on the pedals. Riding a bicycle uphill without pedalling looks stupid.
5. Bike Type (roadster, MTB, trike, others): Early '80s Araya Cro-Mo rigid mixte MTB with an Xtracycle. Bike weighs ~120 lbs with motor and batteries. It also has a comfortable upright riding position.
6. Motor Model: Xlyte 5304R
7. Controller Model: Xlyte 72V 48A digital.
8. Battery: (Voltage/Capacity): 48V 18Ah NiMH, 3C rated.

Note: All 700 km to date have been in hilly urban conditions.

[Kurt]

1. Efficiency 8 -18 whrs km
2. Speed (15-45 km)
3. Gradient mixed
4. Peddling effort none-light
5. Bike Type MTB with trailer
6. Motor Model 5304 26" wheel
7. crystalite 48amp digital.
8. headway 36v 20ah

Kurt.

[paultrafalgar]

Here's the data in a spreadsheet format:

EbikeEfficiency.xls

Microsoft Format

(112.5 KiB) Downloaded 232 times

and

EbikeEfficiency.ods

Open Document Format

(15.01 KiB) Downloaded 142 times

Only one entry per person I'm afraid. Is there any way to put up a spreadsheet and allow each row to be added/edited by only the owner? So that we can collectively build it without having access to other than our own data? Sounds a complex programming task (file locking, passwords etc). Anyone?

[recumbent]

That spread sheet format looks great "Paultrafalgar" Thanks.

I noticed someone with the best efficiency numbers has the heaviest bike with the worst aerodynamic's. Obviosly somethings not calibrated correctly.

[Zoot Katz]

That spread sheet format looks great "Paultrafalgar" Thanks.

I noticed someone with the best efficiency numbers has the heaviest bike with the worst aerodynamic's. Obviosly somethings not calibrated correctly.

yo, you lookin' at me?

I'm an everyday cyclist. Have been for a long time. My fitness level is undoubtedly different than someone who has just recently escaped their cage to adopt bicycling as their primary mode of transportation. I like pedalling and travelling at bicycle speeds. I'm not afraid to sweat or breathe hard.

My Cycle Analyst was set up by the good folks at ebikes.ca so I trust its accuracy. The only thing I changed was the default wheel size after doing a measured roll out. My ebike average speeds are about the same as my unassisted bicycles. Max speeds on my unassisted bikes are generally greater because the brakes are more effective with the lighter bike and the weight distribution isn't fuktup by a bunch of batteries.

I'd like to have a record of how many watts I'm adding.

[recumbent]

yo, you lookin' at me?

Yeah, i think it was, but didn't want to pigeon hole it that much.

Just that I know from experience, 8wh/km, (13 wh/mile) was my absolute lowest daily average only once or twice, and it's difficult to reach unless i was energetic, under ideal conditions.

Don't want to mislead any newbie into thinking this is a common number for us ebikers to achieve, because it's not. Unless of course we input lots of pedal power like you said. That's all.

[317537]

Bike 1:

1. Efficiency 8-10 whrs km
2. Speed (18-27 kph) lots of take off speed.
3. Gradient: two hills
4. Peddling: effort none.
5. Bike: Dyno BMX 20" wheel.
6. Motor: brushled 24v overvolted to 36v chain driven.
7.Controller: Unknown 24v brushed controler overvolted 36v 25A .
8. SLA 3x12v (36v) 18ah

Clocked well over 5000+ kms.

Bike 2

1. Efficiency 10-16 whrs km
2. Speed (22-32 kph).
3. Gradient: two hills
4. Peddling: effort: I like to pedal the MTB, a lil bit to medium.
5. Bike: Huffy MTB 26" aluminium frame 55kgs (with SLAs.)
6. Motor: GM 36v brushless hub.
7.Controller: Zhidong 36v .
8. SLA 3x12v (36v) 18ah

Clocked 1500+ km
Les

[efried]

Hello,

I have read about a Sanyo 2.4kg geared hub motor with regeneration!

do you have a reseller for that?

many thanks

E.fried

[paultrafalgar]

You've probably seen this:
http://www.bikecircle.com/forums/tech-i ... ssion.html
it doesn't help in that it says there is no US supplier.
This also doesn't help with a supplier, but you might not have seen it:
http://techon.nikkeibp.co.jp/english/NE ... 07/154398/
Hope this isn't annoying! Lots of announcements are made by companies before anything is available. It's called vapourware!

[Kurt]

I just wanted to backup Zoot Katz I think If he rides like he said he dose his number would be correct.I posted my numbers for both my dual motor and 5304 .I gave number range that represent how I normally ride the bike and the numbers are kinda average .

That said I have ridden the same bike and use much less power then I normally would I didn't take note of the wh/km but it was a regular ride that is 15km one way I use about 6ah from my pack each way when I ride normally.I once rode that same trip one way on just under 1ah and it isn't a flat ride there is a good mix of hills and flat sections. I put in a solid effort and just used the motor to take the edge off up the hills.

Hey if you don't use the throttle you don't use any power from your battery and if you have a good range of gears you will get there eventually on zero kw.
Kurt.

[cycle9]

1. Efficiency (Watts/mile): 14 to 18, depending on load
2. Speed (mph | kph): Typical average, 18 mph, city + highway riding, 17 miles round trip
3. Gradient (%): moderate hills, 3%, a few short 7-8% hills
4. Pedaling effort (none, light, heavy, extreme): heavy to start, light continuous
5. Bike Type (roadster, MTB, trike, others): Surly Big Dummy longtail
6. Motor Model: BMC V1 geared
7. Controller Model: Various, including BMC 25A, and Crystalyte analog 35A
8. Battery (Voltage/Capacity): Various. Typically LiFePo4 10Ah or 2x10Ah, 36V. Sometimes 48V, efficiency is similar.

[Doctorbass]

1 ) Efficiency - 10Wh/mile AT 22mph
2 ) Speed - 22 MPH cruising on long straights 47mph full speed
3 ) Gradient - Almost completely flat
4 ) Pedaling - never
5 ) Bike - Full suspension mountain bike
6 ) Motor - Xlyte 5305
7 ) Controller - Xlyte 7235 analog, modified with 4110
8 ) Battery - 24s18p Konion 3.7V/4.2V (88.8 volt nominal, 100.8V max 23.1A Ah)
9 ) Max range without pedal 210km finally measured

Doc

[vkruger]

1. Efficiency (Watts/mile): 10 to 12W/mi, depending on how many red lights
2. Speed (mph | kph): Typical average, 14-16 mph, city 23 mile daily commute round trip
3. Gradient (%): moderate hills, biggest 1 mile at 7-9% (have to brake at 45MPH going down)
4. Pedaling effort (none, light, heavy, extreme): medium (motor off above 18mph because of 20" hub wheel)
5. Bike Type recumbent Giro 20
6. Motor Model: BMC V1 geared
7. Controller Model: Crystalyte analog 35A
8. Battery (Voltage/Capacity): 36V - Various LiFePo4 10Ah 20Ah duct tape, Konion 8Ah 12Ah

[cerewa]

This is for the commute I used to do. The motor's controller broke and I switched jobs, and these days I commute without a motor.

1. Efficiency (Watt-hours/mile): 6 - 7 watt hours per mile
2. Speed (mph | kph): 16mph (65 minutes each way, 17 miles each way)
3. Gradient (%): lots of hills, 10% of the distance on flat ground. lots of ~%5 grades, some climbs of ~150 vertical feet in a space of ~1500 horizontal feet (10%).
4. Pedaling effort (none, light, heavy, extreme): medium-heavy
5. Bike Type: mountain bike
6. Motor Model: Cyclone 500W
7. Controller Model: Cyclone 24V, built-in to motor housing (intended for 30A max, I believe)
8. Battery (Voltage/Capacity): YESA 240 watt hour (24V10Ah) LiFePO4. Enough capacity to go about 40 miles with this setup. 20A limit on BMS.

[Toshi]

i think this is an admirable effort. however, i don't think it can be used for straightforward comparisons between gear, as bike configuration (including handlebar/seat height! and tire choice), rider weight, terrain, number of stops/starts, presence of a headwind or tailwind, pace, and riding style/pedaling effort play a HUGE role. i could use 0 Wh/mile with my current setup and have used as much as 37 Wh/mile, after all.

that said, here are my data:

1. Efficiency. 25.89 Wh/mi lifetime average as of today. Scatter plot of energy use over time.

2. Speed. I cruise on the flat at 22-25 mph but my CA-reported average is almost always 15-17 mph due to hills as well as many stoplights and stop signs along my route.

3. Gradient (%). My normal route has 250 feet of vertical gain over 1.22 miles: an average grade of 3.88%. There's a short pitch in there that's probably a 5-6% grade.

4. Pedaling effort. Moderate. My bike is geared such that I can pedal along at a reasonable cadence whether going 5 mph or 30 mph.

5. Bike Type. Flat-bar hybrid with 26x1.75" semislick tires, with handlebars about level with the seat.

6. Motor Model. Crystalyte 407 in a 26" wheel.

7. Controller Model. Crystalyte 72V 20A pedal-first controller.

8. Battery. 48V 12Ah prismatic ebikes.ca LiFePO4.

[bbushwacker]

1. Efficiency. 29.7 Wh/mile 18.5 Wh/km (average, going both directions)

2. Speed. max 34km/h

3. Gradient (%). pretty steep, estimated 100m elevation gain over 1km, rest flat

4. Pedaling effort. Minimal, only on hills, throughout acceleration and to pass others

5. Bike Type. Heavy full suspension downhill frame with knobby off-road tires

6. Motor Model. Ezee, rear with disc

7. Controller Model. Ezee, limited to max 17A min 39V to reduce the risk of frying more MOSFETs

8. Battery. 48V8Ah NiCd

[floatbike]

1. Efficiency : 14 WHr/Mi
2. Speed (mph | kph): 20mph max, 16mph cruise
3. Gradient (%): flat with a few steep hills
4. Pedaling effort (none, light, heavy, extreme): moderate pedaling all the time, heavy up hills
5. Bike Type (roadster, MTB, trike, others): 24lb aluminum folder
6. Motor Model: GoldenMotor Geared Mini Motor
7. Controller Model: GoldenMotor Cruise Controller with Regen
8. Battery (Voltage/Capacity): 38.4V 10AHr GoldenMotor LiFePO4

I used to race cross country MTB, now 15 years later I am slower with electric assist than I used to be unasisted!

[icecube57]

1. Efficiency : 18-24wh per mile
2. Speed : 30mph on flats 36mph down hill
3. Gradient : 1-2% on the trail that I ride
4. Pedaling effort : Light Pedaling
5. Bike Type: Next Mountain Ridge MTB
6. Motor Model: Golden Motor 1000w
7. Controller Model: Golden Motor Stock 48v 30A
8. Battery (Voltage/Capacity) 48v 20AH Ebay Duck Tape (NON PING)

[MartyK68]

It would've been nice to see everybody's weight...

[urace4me2]

Just did a test yesterday:
1. Eff: 11.5 watt hour per mile 37.5 miles, 1:48, batteries never quit even though the last 3 miles or so I didn't pedal at all. so actual achieved efficiancy was higher and could have been much higher had I kept pedaling 'til batteries got below low volt controller threshold.
2. Spd: 24mph was the max speed I could feel the motor helping. Top speed by myself with motor turned off was 28 mph on the flats. After 30 miles I could still get 21 on the flat without pedaling.
3. Gradient: dead flat.
4. Pedal effort: Extreme. 90% of the ride was pedal unassisted for 10 to 60 seconds then use a electric burst to rest for 10-60 seconds. Probably less than 50% assisted time. Used pedals to get rolling but motor to help get from 4 mph to 20mph.
5. bike: Giant Sedona ATX (1994) clipless pedals to allow "full circle" pedaling. 1.7 inch wide almost slick road type tires pumped to 60 psi
6. motor: Amped bikes kit
7. controller: Amped bikes kit
8. battery: Jupiter battery 3 X 12 volt 12 ah AGM SLA

Thrilled with the range!

[Russell]

Just did a test yesterday:
1. Eff: 11.5 watt hour per mile 37.5 miles,
8. battery: Jupiter battery 3 X 12 volt 12 ah AGM SLA

Thrilled with the range!

Hello urace4me2,

What are you using to measure the energy consumed from the batteries or are you giving us your TOTAL power (you and batteries) from a PowerTap hub? I ask because when folks here talk about efficiency the Wh/mile numbers are JUST what the batteries provide and there's no way 3-12V/12Ah batteries can provide 431Wh (11.5 Wh/mi x 37.5 mi) of energy unless they are discharged completely at a 20 hour rate.

-R

[urace4me2]

I did math assuming 36v12ah capacity (432 watt hr) spread over 37.5 miles. It assumes the batteries were totally used up. Of course this is false but it errors on the side of indicating less efficiency than actually achieved. It is the battery power I used up during my 37.5 mile assisted ride (assuming they quit on me, but they didn't). I think what's so different is I was putting out some serious watts with my legs. It was more a test of how far those batteries could "help" me maintain a speed average of over 20, while saving me from having to put out an all out race level of effort. Total run time was 1:48 but throttle was off for probably 50% of the time. I milked those SLAs really slow.