DIY Electric Car Forums banner
1 - 13 of 13 Posts

· Registered
Joined
·
667 Posts
Discussion Starter · #1 · (Edited)
A job change for my wife has changed my mission. She just took a job with a 75 mile highway commute each way.
I'm operating on the presumption that a 8+ hour midday recharge is going to be doable. I realize that without it the task is virtually impossible.

Seeing conversions like the Red Beastie:

http://www.evalbum.com/037

and the toyota xtracab:

http://www.evalbum.com/1430

Makes it seem possible to put together a long range lead acid truck though it'll drive like "a cement truck".

I know it'll have to carry (literally) a ton of lead. The question is how to best package that lead to get the best range out of it.

Suggestions for a platform to carry it? And no LiPo isn't an option. Can't justify $25K+ for a pack to do the job.

ga2500ev
 

· Premium Member
Joined
·
927 Posts
Pretty much your only option is a pick-up with a tonne of lead. I'd probably go 144-156V with a 9 inch motor minimum, and a tonne of trojans. You'd probably want some aero-mods too. What is your motivation for going electric for the commute? I just don't know if it works out either money or efficiency wise to carry that much lead. I'd just buy a honda insight and get 70mpg on the highway, that ~2 gallons for the round trip.
 

· Registered
Joined
·
667 Posts
Discussion Starter · #5 ·
Pretty much your only option is a pick-up with a tonne of lead.
That's what I've figured. I can't get any GVWR on vans or mid sized SUVs as a possible platform so far.
I'd probably go 144-156V with a 9 inch motor minimum, and a tonne of trojans.
I wonder why no one has a system voltage of 150V? If you're running 6V batteries, what's wrong with having exactly 25 of them?

I also wonder is there some pivot where it's better to split the pack as opposed to continuing to run up the voltage. The Red Beastie carried 40 6V batteries arranged in 2 120V strings. But that's a whole lot of lead to be slinging around. Say you're comfortable with 30 batteries. A 180V pack will severely limit your motor choices. But would you lose significant capacity to Peukert if you ran 2 strings of 90V?

My current thinking is that if I want the pack to last more than a few cycles, it can't be discharged to 80% DoD each and every run the vehicle makes. So that means either the batteries are going to have to carry more Ah (like the EvIII under 1724) or up the voltage nearer to 200V.

Now when it comes to batteries, I know it's an issue of you get what you pay for. But when it comes to cost/Wh what's the justification for buying Trojans or frankly anything else other than the Johnson Controls 6V 225Ah LA badged as the Eveready GC2 at Sams? At $75 each including the core charge, that's less than half the price of a Trojan T-105 for the same capacity. The fact that they are cheaper means that you can actually sling more lead into the pack, which in theory would make the pack last longer.

You'd probably want some aero-mods too.
Definitely. I've already been reading on ecomodder. I'm wondering if mirror deletes are street legal if you replace with interior side mirrors. But the angled bed cover, front dam, belly pan, wheel covers, and lowering the chassis are all on the table. This is a no brainer because every watt I can save in the pack and not give to the pavement will improve both the cost and the pack of the vehicle.

What is your motivation for going electric for the commute? I just don't know if it works out either money or efficiency wise to carry that much lead. I'd just buy a honda insight and get 70mpg on the highway, that ~2 gallons for the round trip.
Fair question. There are a bunch of factors:

1) Controlled costs. Gas costs are spiraling out of control with no end in sight. One cannot budget for gas yet one must absolutely have it in order to function in a gas vehicle. Electricity cost less per mile to operate and Electric utilities are a state regulated monopoly. So they cannot jack up prices without putting in a formal request.

2) Comfort. My wife is driving a big SUV right now. She's not going to be happy riding around in a low slung, cramped sedan. So any compromise I can make between the two will help.

3) Shared costs. One recharge a day will be at work. So her job will be sharing the cost of the commute.

All of this is still in the feasibility stage. The only known advantage I have right now is that she does know how to drive a 5 speed.

I wonder how easy it would be to get a truck and load it up with 3/4 ton worth of load just to test its drivability?

ga2500ev
 

· Registered
Joined
·
37 Posts
I wonder how easy it would be to get a truck and load it up with 3/4 ton worth of load just to test its drivability?

ga2500ev
Haul some fill dirt? You could also try water. get 200 one gallon jugs and toss them in, or rather arrange them neatly. keep in mind the weight changes with the loss of the engine. I'd assume that since the engine is leaving the front, you'd like to put some batteries up front. Since the engine is there during this test drive, you could assume that its weight is representative of the electric motor, controller and a few batteries, then take that battery weight off of the total that you add to the bed.

Weight distribution really affects handling, so don't add too much to the rear.
 

· Registered
Joined
·
324 Posts
2) Comfort. My wife is driving a big SUV right now. She's not going to be happy riding around in a low slung, cramped sedan. So any compromise I can make between the two will help.

ga2500ev
IMHO, there's 99% of your challenge right there. If your wife's not fully on-board with the project, don't bother starting until she is. A lot of men fail to take into account the MASSIVE effect their spouse can have - either to support or hinder any project. KiwiEV really got me thinking with some of his comments about his wife's support, so I've spent about 2 months gently getting my wife to accept and support the project.

Right now, she's still not 100% convinced, but guess what came out of the blue last night? We're in bed, just chatting a little before going to sleep. She says "If you convert the Pulsar to batteries, I want to convert the Neon to LPG." I almost fell out of bed. Talk about a U-turn... Putting a 2L 4-cyl Crysler Neon on LPG probably isn't the MOST effective gas conversion, but it will sure reduce our costs (here in Brisbane LPG is quite cheap and Australia has way more LPG than we know what to do with. We sell it to China for $1 per tonne).

Maybe sitting down after dinner with a glass of wine and talking about the costs (total costs ie opportunity costs as well) of running an SUV might come in handy? Once she realises the cost of maintaining her comfort in an Armoured Personnel Carrier, she just might demand that you sell it and buy her a SmartCar ForTwo. Women sure can surprise us, sometimes...

Maybe do a little internet research on the psychology of power and motor vehicles... If you can replace the feeling of power (from driving a tank) with a feeling of power over the gas companies (by driving eco) - you might be onto something.

Here in Australia it's a little different. We generally consider that the people who are "compensating" don't drive Hummers, they drive turbo Skylines or NSXs or Imprezas... One of our motoring organisations even ran a series of ads where cute girls wiggle their pinkies at men showing off by driving dangerously.

http://au.youtube.com/watch?v=5hWxU_ICoHM

They are trying to break the psychological link in the men's minds between power (and desirability in the eyes of the girl) and the fast, dangerous (and gas guzzling) cars.

I'm not saying your wife is compensating for having a small penis by driving an SUV - that's a ridiculous stretch. What I'm saying is - if you can replace the feeling she gets by driving the SUV with a SIMILAR feeling derived from saving money, the planet and not funding the Saudi's who perpetrated the September 11 attacks - you just might find yourself married to the world's leading EV advocate...

And that would save a lot of lead. Reducing the need for a large vehicle can reduce the cost and complexity of the whole project.

</rant> :p
 

· Registered
Joined
·
680 Posts
A job change for my wife has changed my mission. She just took a job with a 75 mile highway commute each way.
I'm operating on the presumption that a 8+ hour midday recharge is going to be doable. I realize that without it the task is virtually impossible.
I'm definitely not trying to be out of line here, but is it practical to even have a job with a 150 mile/day commute whether or not your vehicle is fuel/electricity efficient?

Instead of an 8+ hour work day, it's really a 10.5+ hour work day. In one year your wife will log 39,000 miles, and a significant part of her life will be watching yellow stripes pass beside her.

Personally, I don't think any job is worth that commute.
 

· Registered
Joined
·
324 Posts
I'm definitely not trying to be out of line here, but is it practical to even have a job with a 150 mile/day commute whether or not your vehicle is fuel/electricity efficient?

Instead of an 8+ hour work day, it's really a 10.5+ hour work day. In one year your wife will log 39,000 miles, and a significant part of her life will be watching yellow stripes pass beside her.

Personally, I don't think any job is worth that commute.
Hehehee...ClintK, you just described the thousands of people who work in Sydney and commute from the Central Coast or Penrith or Wollongong. The freeways are jammed - just like California and if there's a smash...3 lanes down to two - forget about it! I used to live on the Central Coast and take the train - it's 2.5 hours EACH WAY on the train. Each carriage is full and there are people standing...

I moved to Brisbane 2 years ago and I'm planning to drive my ev-pulsar 22km to work and back. Takes about 20 minutes.

I agree - that job better be providing a lot of something in return for the commute.
 

· Registered
Joined
·
667 Posts
Discussion Starter · #10 ·
I'm definitely not trying to be out of line here, but is it practical to even have a job with a 150 mile/day commute whether or not your vehicle is fuel/electricity efficient?
Here in the Atlanta area there are a whole host of folks who do very long commutes. Some live in South Carolina. Some in Alabama. Many commute from one side of town to the other, which is upwards of 50 miles each way.

I have two colleagues one of which has a 45 mile commute each way, the other with a 60 mile commute. I have a friend who commutes 65 miles to work.

Instead of an 8+ hour work day, it's really a 10.5+ hour work day. In one year your wife will log 39,000 miles, and a significant part of her life will be watching yellow stripes pass beside her.

Personally, I don't think any job is worth that commute.
Some mitigating circumstances:

1) It's only 200 days a year.

2) After one year we'll probably move.

3) The job represents significant career advancement.

It's like jobs where folks travel 80% of the time. Sometimes it just has to be done.

ga2500ev
 

· Registered
Joined
·
667 Posts
Discussion Starter · #12 ·
Put a diesel generator and your charger in a trailer and run that off cooking oil.
There wouldn't need to be a need for a trailer. If the series hybrid route were taken, then the genset would need to be carried onboard.

The key to a range extender would be that it's operation would need to be automatic. Something like it would kick in at highway speeds and that it would continue to run until the battery pack was recharged to 10% DoD. the only think the operator would have to do is fill it with fuel.

What I haven't figured out yet is how to size the genset. Say you have a 7.5 kW genset. So it has the power capacity of of 7.5 kWh right, because if you ran it for an hour producing 7.5 kW...

Now say you have a truck that takes 500 Wh/mile @ 70 mph. So in a hour it would take 70*500 = 35000 Wh or 35 kWh.

Seems like a total mismatch. But it does show that driving faster does suck down more power, yes?

So while the genset will help offset some of the power used, it seems that lowering both the speed and the Wh/mile are both much more ciritical factors.

ga2500ev
 

· Registered
Joined
·
528 Posts
Considering the cost of higher performance batteries is out of your budget, I'd doubt any new emerging technologies would be any more affordable. We pretty much have what we have when it comes to EV parts and options. There just isn't alot of research going on or we just don't know about it. I'd place my bets on the latter. Best you can do is pick a light car, choose low rolling resitance tires or over-inflate good old radials but that's not recomended by the manufacturers for safety and handling reasons. Use light weight synthetic oils in your drivetrain helps more then you think. Enough that you'll see it on the amp gauge. That reminds me of how important the tires really are. When I did my EV Geo, the car had old, hard, dry-rotted tires on it. That was one of the last things I bought. There is a piece of road I drove on that's pretty flat. Speed limit is 30 so I'd be doing 30-35ish. With the old tires I'd pull 30amps. When I finally got new tires for the car that current went to 40amps for the same speed. That's 33% more power at only 35mph just due to tires.

Generators can be automated to start and stop bassed on your pack voltage. Someone would need to design that control system. I looked into putting an 8hp engine in the Geo once. I was going to use an electric clutch and couple it to the traction motor. When the batteries got low -click!- put-put-put-put-put. If the gas engine put out more power then I was using to drive I'll be charging. With the proper controlling ofcorse.

The generator may not make more power then your traction motor is using but the fact is it's less off your batteries = more range. Plus you can't get stranded with dead batteries.

I forgot... 35,000 seems a bit high. I knew a guy who put an 8?hp snow blower motor in a bug. The top speed was 65mph! 8hp = 5968watts. If the generator can do 7500 watts x .88% (Typical ADC motor efficiency) that's 6600. There is 632 watts going back into your batteries in that example. Obviously an EV is heavier then a 8hp VW Bug but the numbers are alot closer then 35,000watts.
 
1 - 13 of 13 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top