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[motorrad36]

I have been thinking a lot about how much my brain has shifted from range anxiety to near-total confidence in my Zeros since becoming an owner. While thinking about that, I realized it may have been helpful to have some experience driven rules of thumb for new riders or anyone new to electric bikes. I am currently planning a trip from Sacramento to South Lake Tahoe and doing my best to make the driving part of the trip free or nearly so. The math side of my brain likes to see numbers, so I have been trying to come up with an estimator for calculating range, especially climbing in altitude. As a newbie it could've been useful to have a chart that shows distance per kWh, with an additional way to see how increases in elevation can affect consumption.

I stumbled on this energy converter, and it already had a Zero SR in the calculations! https://www.digitaldutch.com/unitconverter/fuel_consumption how cool is that! It seems fairly accurate...my 106mi trip to SLT would take about 5 gal in gas in a little commuter car due to the climb, which the calculator says about 18kWh. Sounds about right to me, as I was planning on stopping halfway (El Dorado County Dept. of Transportation has free charging) or so to top off the charge before the steep part of the ascent. I will try to log my miles and consumption and compare.


Maybe I overthink these things...

[BrianTRice@gmail.com]

That's pretty interesting, but there's no single number for "kWh to miles".

Here's how I had a rule of thumb for my 2013 DS, which didn't show digital SoC, but instead had 11 bars to cover the capacity of the 11.4kWh (max) battery:
- Each bar would yield 5-11 miles, depending on how fast I rode. 5 miles at 70+mph, and 11 miles at neighborhood speeds (25-30mph).

It is good to just have a single number to throw around, but make sure that number reflects the average way you'd drive that you're estimating.

But, just remember, the worst case will be worse than even the official estimates, because if you ride in the cold and rain uphill at highway speeds into a headwind, you'll get quite a bit less range.

Sorry, I can't make this simpler for you, but there are route planners that incorporate efficiency changes for your travel, because it IS complicated and you can get stranded if your plan doesn't involve a nice padding to your estimate.

[Crissa]

Yeah, mostly what i've been doing is memorizing how much power it takes to go between two points.

So like, up the hill is 20-25 points.  Down is 10-15 points.  To and from Santa Cruz from home is 26.  To and from Scotts valley is almost 20.

-Crissa

My usual power usage as a newbie was between 40-60 Wh/mi but now it's pretty consistently 75.  Whoever had it before had it pinned at 100.

[DonTom]

I am currently planning a trip from Sacramento to South Lake Tahoe and doing my best to make the driving part of the trip free or nearly so.

That's 100 miles mostly uphill on US 50 and probably somewhat of a high speed to keep up with traffic.  I hope you plan recharges on the way.

When I want to go as far as possible on Hwy 80, I get behind a slow truck, especially for uphill. Put not nearly as many trucks on 50. I can almost choose my speed by truck on I-80.

You waste more time by speeding on any Zero as the charge times are a lot longer than any gain you can get by speed.

On any Zero  motorcycle, when you're in a big hurry to go a long distance, ride as slow as possible.

I have taken my 2017 SR w/ pwr tank between here and Reno several times. I need at least one charge stop. I charge at ~6.4 KW (one 2.5KW Elcon in each saddle bag).There was one time I think I could have made it without a recharge, a warm day when I was stuck in a lot of slow traffic (I rarely lane split, even though legal here in CA <unlike NV>)  going west from Reno to here, which is more downhill than uphill. Going east will be mostly uphill.

-Don-  Auburn, CA

 

[motorrad36]

That's pretty interesting, but there's no single number for "kWh to miles".

Ok fair enough but we have access to the math required to come up with a DANG close estimate, isn’t it just a matter of gathering data? I think we could build a database using our own app logs. Add in a little additional input for factors like wind speed...

Maybe zero is thinking about the gauges wrong. I know some hybrid have a feature that shows estimated per gallon range but the gauge goes to 60+mpg when using the batteries to cruise control and the engine in nearly idling. We could have one that shows an estimated mpkWh, the bike can already broadcast a large portion of data needed I think.

[TheRan]

There's already an average efficiency number that can be shown on the dash, I think it may be kW/h per mile/kilometre. That average is taken over a charge cycle (resets after a full charge) and is fine if you're always taking the same route at the same speed at roughly the same temperature. For going anywhere else, at a different speed, at a different temperature, it can only serve as a rough starting point.

[Richard230]

I am an easy rider and try to get the most out of my battery pack.  I find that I can travel 1 mile at .6% SOC at an average speed of 35 mph and about 1% per mile at 55 mph.  But head or tail winds and especially air temperature can have a very dramatic effect on the range per KWh.  Personally, I have found that the range remaining indicator at the upper screen display of my 2018 S with PT, appears reasonably accurate, provided that your riding speed and environment remains the same.  If it changes, so will the range estimator.  It will jump up and down with the times. 

[motorrad36]

That's 100 miles mostly uphill on US 50 and probably somewhat of a high speed to keep up with traffic.  I hope you plan recharges on the way.

Yep, EDC Dept of Transportation and then maybe a top up in Camino. Is this Don at the Placerville Park and Ride?

[BrianTRice@gmail.com]

That's pretty interesting, but there's no single number for "kWh to miles".

Ok fair enough but we have access to the math required to come up with a DANG close estimate, isn’t it just a matter of gathering data? I think we could build a database using our own app logs. Add in a little additional input for factors like wind speed...

Maybe zero is thinking about the gauges wrong. I know some hybrid have a feature that shows estimated per gallon range but the gauge goes to 60+mpg when using the batteries to cruise control and the engine in nearly idling. We could have one that shows an estimated mpkWh, the bike can already broadcast a large portion of data needed I think.

FWIW I am working on a project to do just that, but the critical element that the bike can't log and is hard to measure is wind speed and direction.

Ambient temperature is available but not humidity, precipitation, or air pressure, although those can be derived from local weather stations (assumes GPS on a logger along with a reasonable way to determine the closest reliable station). With GPS, timestamps that match the bike's, and a network connection, one can work out elevation changes and weather in order to provide a very accurate estimate, but without those, these variables are hidden and make estimates seem very unreliable.

[BrianTRice@gmail.com]

There's already an average efficiency number that can be shown on the dash, I think it may be kW/h per mile/kilometre. That average is taken over a charge cycle (resets after a full charge) and is fine if you're always taking the same route at the same speed at roughly the same temperature. For going anywhere else, at a different speed, at a different temperature, it can only serve as a rough starting point.

FWIW, historically, this figure has read low. That is, about 15% more power is used per mi/km than indicated. There is some inherent noise in current measurements, and this figure is basically power/speed or current*voltage/speed, but I recall there being a hypothesis about another factor involved which I don't recall offhand and maybe wasn't fully confirmed.

I will say that before the SoC reengineering tumult of 2017, this figure and the distance remaining estimate were stable; distance remaining was more accurate except when cel imbalance gets out of hand due to pack cooling from cold/wet air. Unfortunately, the SDS dash is incapable of revealing this, too, forcing consulting the app which is onerous.

[DonTom]

Yep, EDC Dept of Transportation and then maybe a top up in Camino. Is this Don at the Placerville Park and Ride?

Sure looks like my SR, but no, I don't think I have ever been there with my Zero SR. Besides, I have not used Delta Q chargers on the road for around a year. I take two 2.5 KW Elcons  for my longer rides on my SR.

At almost every charge station I have been to, I have at least one  check-in and photo on Plugshare. The last place I charged on the road was here. Using a Tesla Destination charger on my Energica.

-Don- Auburn, CA

[togo]

> There's already an average efficiency number that can be shown on the dash, I think it may be kW/h per mile/kilometre. ...

Watt-hours per mile or km, either instant or per-trip.

Trip meter does reset on charge to 100%, yes.

A trick Harlan showed me (when I bought my 14 SR ZF 11.4 with 10 kWH usable), was to track my percent against my trip miles, and to adjust speed so I was going 1% per mile, so my miles and percents would tick together, add up to 100, if I wanted to get 100 miles range.  Sadly, that particular bike would often run out of power at 6%. 

Rapid charging is what got me out of the range maximization / range anxiety mindset.