200 miles one way @ 70mph crusing speed. What would it take?

[gast42]

What's the most realistic option of building/converting a vehicle that can make a long range commute for one person and keep the total cost under $0.15 a mile?

10k miles per year
200 miles between charges
70 mph cruising speed preferred
50 mph cruising speed minimum

I'm new to all this so I just want an idea of what my realistic options are.

 

[dogman dan]

Lasso a truck with your bicycle. Seriously though, since the cheapest thing with that performance is an ICE car, and mine range from 25 cents a mile to 65 cents per mile including ALL costs of ownership, how in the heck can an EV go 200 miles at 70 mph without costing like the one that claims to, the Tesla? That kind of performance needs about $50,000 worth of a123's. My cheapie lithium ebike is at about 7 cents a mile, so i guess for about 15 cents you could maybe go 50 miles at 30 mph with about 50 pounds of lithium batteries. Some of the smallest lead powered car conversions may be just about as cheap, but range is under 10 miles with so few batteries.

 

[Drunkskunk]

What's the most realistic option of building/converting a vehicle that can make a long range commute for one person and keep the total cost under $0.15 a mile?

10k miles per year
200 miles between charges
70 mph cruising speed preferred
50 mph cruising speed minimum

I'm new to all this so I just want an idea of what my realistic options are.

possable, but your build budget would be well over $50,000
the technology has arived to do it, but the cost of the batteries would be so high as to make it impracticle.

batteries have an energy density much lower than gas or diesel, making it impracticle for long range. for trips under 10-20 miles, its perfect.
Its a matter of matching the right technology with the right application. You'd no more want an electric for long comutes, than you would want an airplane for flying 2 blocks over to the corner store.

 

[TylerDurden]

Hi Gast,

We could achieve those goals and downgrade to the level of practicality...

70mph for a bicycle = 5kW
200mi @ 70mph = 2.8hr
5kW * 2.8hr = 14.2kWh
14.2Kwh / 72V = 198Ah

batteries = 5 packs @ 72V 40Ah = $15,000.00 approx.

@ 50mph simply divide by three.

 

[gast42]

Hi Gast,

We could achieve those goals and downgrade to the level of practicality...

70mph for a bicycle = 5kW
200mi @ 70mph = 2.8hr
5kW * 2.8hr = 14.2kWh
14.2Kwh / 72V = 198Ah

batteries = 5 packs @ 72V 40Ah = $15,000.00 approx.

@ 50mph simply divide by three.

500 charging cycles seems a bit much to ask of current batteries, and from my understanding I'd need 6 packs to prevent from quickly killing the batteries from deep cycling? Then again after a few searches, I'm seeing 2000-5000 charging cycles quoted on some packs?

So $18k for batts. But doing 70 on a bicycle seems... I don't know, dangerous perhaps? ^_^ That and while I"m not sure how big those packs are I've seen some image and I'm pretty sure 6 packs wouldn't fit on a bicycle without some feat of engineering capable of breaking the laws of physics or perhaps space-time. I think I need a bigger box...

You also didn't in include the weight of the batteries in your calculation. A battery pack is, what, 30lbs? So 200lbs of batteries, +me +cargo +frame + wheels. We'll put me and cargo together @ 200lbs. Give another 100lbs for motors and electronics? Before the frame and wheels we're at 500lbs

500 (lbs) * 4.5 (lbs to N) * 32 (meters per second) = 72 kWh ? (A bit more than 5kWh. You had the bike @ 35lbs?)

If I'm going to spend $20k on a a vehicle I might as well be able to drive it in the rain. The weight of a Mini is around 1500 lbs. I'll guesstimate that 500lbs is wrapped up in ICE dead weight, leaving 1000lbs for frame and wheels.

1500lbs total weight. * 4.5 (lbs to N) * 32 (meters/second) = 216 kW...

Hrm. Let's try that @ 50 mph, or 22 m/s.

1500 * 4.5 * 22 = 148.5 kW... still way more than 5 kW

Before I get too much further, do these numbers sound about right?

 

[TylerDurden]

Before I get too much further, do these numbers sound about right?

Maybe not...

Before you consider a warp in the continuum, remember the newfangled invention: "the trailer".

Not sure what 100lb motor you are looking at... a perm weighs about 45lb, a 5kW 5304 = 25lb.

Add 120lbs for batts, since 80lbs is already factored for the bike.

50mph = $5000 in batts, $700 for motor/electrics, $800 for bike & trailer.

If getting wet from rain makes you squeemish, get a velo (and go faster or farther).

 

[michaelplogue]

For a 70mph cruising speed, of course a bicycle would not be a viable option. The 'smallest' you would want to go with would be a motorcycle conversion. But even then I think you'd have problems dealing with all the batteries that would be required to get that 200 mile distance. For these specs, I think you would be better served with a hybrid, such as the VentureOne (Carver).

http://www.flytheroad.com/

 

[TylerDurden]

I don't know what "Electronic LSD" is, but I'm willing to try it.

 

[michaelplogue]

I don't know what "Electronic LSD" is, but I'm willing to try it.

(see my avatar......... :wink: )

 

[TylerDurden]

Not sure what 100lb motor you are looking at... a perm weighs about 45lb, a 5kW 5304 = 25lb.

Predator = 6kW @ ~2lbs. >85% eff.

http://www.icare-rc.com/plettenberg_terminator.htm


Matt's build:
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=3904

 

[dogman dan]

Do you need 200 mile range everyday? or just occasionally. Build a reasonable car or motorcycle conversion that can do 50 miles at 50 mph, and rent something to go further, or build a generator trailer.

 

[gast42]

Do you need 200 mile range everyday? or just occasionally. Build a reasonable car or motorcycle conversion that can do 50 miles at 50 mph, and rent something to go further, or build a generator trailer.

I need it an average of 4 times a month (2 round trips). That distance comprises 90-95% of the milage I do on my car. I should check the altutide change on that trip to find the average grade...

For a 70mph cruising speed, of course a bicycle would not be a viable option. The 'smallest' you would want to go with would be a motorcycle conversion. But even then I think you'd have problems dealing with all the batteries that would be required to get that 200 mile distance. For these specs, I think you would be better served with a hybrid, such as the VentureOne (Carver).

You know, I might buy one of those, but that's a minimum of 1.5 years out. I'd rather start something in the next 1.5 months if I can. All electric would be prefered, but I understand energy density issues there. Is there a seat of the pants number for the efficiency difference between an ICE and a generator trailer?

Before I get too much further, do these numbers sound about right?

Before you consider a warp in the continuum, remember the newfangled invention: "the trailer".

Not sure what 100lb motor you are looking at... a perm weighs about 45lb, a 5kW 5304 = 25lb.
Add 120lbs for batts, since 80lbs is already factored for the bike.
50mph = $5000 in batts, $700 for motor/electrics, $800 for bike & trailer.
If getting wet from rain makes you squeemish, get a velo (and go faster or farther).

I can't reproduce the numbers on that chart, so help me with my math. We want watts. So:

1 Watt = 1 Newton * (Meter / Second)

We have pounds and miles per hour so:

1 pound = 4.45 Newtons
240 pounds = 1068 Newtons

1 mile per hour = 0.45 Meters / Second
50 mph = 22.5 Meters / Second

22.5 m/s * 1068 N = 24030 Watts

That's a factor of 10 difference. Where's my extra zero comming from? If I am wrong that would bring my budget down to 15kW which is much more reasonable (but still a lot). Wait. That the energy needed to go from 0-50, once you get up to speed relitivity kicks in, so the only extra energy I need is the energy to overcome friction (wind, road, and mechanical). I wonder if that factor of 10 is by chance, or if that can be used as a rough guide.

I wasn't looking at a given motor for the 100lb weight, just pulling a nice round number out of the air, but I was also thinking a BMS, speed sensor, etc. I chose the car body for simplicity for the most part. I still want more than a bicycle tire at 50+ mph. A 1" wheel just doesn't seem safe or reliable at those speeds, but then maybe that's just my perception.

 

[michaelplogue]

Perhaps a BugE might be a good vehicle to start with. Allows for customization and 'should' have sufficient space for additional batteries.

http://harveyev.com/bugE/index.shtml

http://electromotiondesign.blogspot.com/

(Detailed blog on Lithium conversion)
http://www.nappepin.com/LithiumEV.htm

http://www.youtube.com/watch?v=I5Az1Tpzccs

 

[TylerDurden]

I can't offer you a working web-calculator right now, but here is some math to play with:

 

[dogman dan]

Yeah thats too often for renting unless the boss pays for it for work. If you live in a state like California, a second ICE car can get pricy to own too. A lot of us run something like a bike or an e-vehicle of some kind all we can, but still have an ICE car around for what the electric can't do. I'm close to the practical limits of ebikes with a 29 mile round trip to work, but it works ok for me since I have more time than money. But the ebike has the virtue of needing no tags or insurance beyond my health insurance. Hopefully I will eventually gather enough battery for a nice motorcycle conversion.