Roll system for Quick charging with Regen Brakes

[harryjpowell]

So I saw the video of the tow charge (not recommended), interesting and an off topic of Regen efficiency with the brakes. Why can't one put this roller system in a pit, pull up to a preset parking spot and start spinning.

Seems to me this would be hugely cheaper than a fast DC charger and you could get close to the quick charge time. You could run it off some dual electric motors or one.

It would be interesting to see some results of doing this just in ECO mode and with an active participant holding some brake...

 

[EVDRIVER]

Much lower efficiency, not exactly cheap or space saving, high maintenance, high liability and not very safe, noisy, etc, etc. It does not make sense for a multitude or reasons.

 

[travisty]

I highly doubt this is very efficient. There is a lot of energy lost from friction. There's also safety concerns due to the roller rolling where there are going to be people's feet.

 

[tps]

Much lower efficiency, not exactly cheap or space saving, high maintenance, high liability and not very safe, noisy, etc, etc. It does not make sense for a multitude or reasons.

+1 - economy of scale will eventually bring QC prices down to the point where we wonder why we were having these discussions in the first place. There is nothing inherently expensive about a quick charger (or an EVSE, for that matter). CDs weren't so practical when they were introduced, either, what with players going for $1K and limited titles available. Demand for CDs built slowly over several years, almost 15 to be exact; demand for EVs and chargers may follow a similar trajectory. I don't see "roll charging" as part of the EV future.

One thing does puzzle me, though: the plans to put L2 chargers at service plazas and rest areas on the freeways. I would think that quick charging would be the only way to go in these locations... If I, for instance, take my (future) LEAF on a trip on the Turnpike I can't imagine sitting for hours at a service plaza recharging. But I also can't imaging sitting there for an hour on rollers with my foot on the brake, either.

Nissan has already made a major step by introducing a $10K quick charger in a world of $30K quick chargers, and that's only the start!

 

[SierraQ]

You wouldn't need your foot on the brake. You can get full regen in ECO mode just by coasting at sufficient speed.

I'm not endorsing this idea but I think it does provide another unusual charging method. Run out of juice... pull into the nearest mechanics shop, ask if you can use their roller.

 

[TonyWilliams]

This has been brought up previously. If DC fast chargers were truly free to install, it doesn't cover the huge fees associated with it from CPUC and your local California Public Electric Utility.

The same applies to these spinning wheels ideas. Where would the power come from to spin the wheels at 30kW, plus all the frictional and mechanical losses, pushing the load on an electric powered system to close to the load of a DC fast charger.

Again, if all the hardware were free for any recharging scheme, pulling a grid load of over 20kW in California will be expensive.

 

[tps]

Again, if all the hardware were free for any recharging scheme, pulling a grid load of over 20kW in California will be expensive.

This too, may change as EVs become more accepted.

 

[cwerdna]

I'd rather have tow charging (assuming it ever gets Nissan's blessing) as it would serve two purposes: charging and getting you closer to your destination.

edit: Oh yeah, no need for special charging equipment either.

For the few here who haven't seen the video the OP's referring to, check out the crazy Dutch guys at http://www.green.autoblog.com/2011/05/25/is-the-quickest-way-to-charge-a-nissan-leaf-by-towing/" onclick="window.open(this.href);return false;.

 

[EVDRIVER]

I'd rather have tow charging (assuming it ever gets Nissan's blessing) as it would serve two purposes: charging and getting you closer to your destination.

So tow the car backwards with the front wheels on the ground. I knew this thread would go on and on :lol: How about a horse trailer with a tread mill.

 

[TEG]

How about a horse trailer with a tread mill.

Sure! Why not?

(Only 1hp drivetrain, but runs on flex-fuel. Sorry, not zero emissions...) :lol:

 

[adric22]

One thing does puzzle me, though: the plans to put L2 chargers at service plazas and rest areas on the freeways. I would think that quick charging would be the only way to go in these locations... If I, for instance, take my (future) LEAF on a trip on the Turnpike I can't imagine sitting for hours at a service plaza recharging. But I also can't imaging sitting there for an hour on rollers with my foot on the brake, either.

Well, it seems silly to put an quick-charge station and not also offer L2 for a minimal increase in cost. True, I wouldn't want to sit at a rest stop for 8 hours while my Leaf recharges. However, if the L2 station supports the full 80 amps then it is possible some time in the future that a Leaf or similar vehicle might me able to charge in 2 hours. Maybe 1.5 hours for 80% charge. While still not desireable, it is also not an unreasonable amount of time either. For example, if I needed to get from Dallas to Houston it is a little over 200 miles. I'd need to stop and recharge at least twice in a current model Leaf to make that trip. That means you'd spend 4 hours charging, and about 4 hours driving. That makes for an 8 hour trip. With current L2 on the Leaf it would be about a 20 hour trip. With quick charging it would be around 5hours.

Keep in mind that some of us (like me) don't even have a QC port on our Leaf. And while I probably wouldn't want to make that trip to Houston in my Leaf (although I suppose it could be done) it might not be unreasonable for me to take a trip half of that distance using L2 capabilities.

 

[camasleaf]

Public L2 can only be a temporary solution until the EV number increases. What are we going to do, have L2 charger at every parking spot? Keep half of the parking around the store entrances for EVs?

In my opinion L2 is a waste of public money if they are not next to a quick charger for charging above 90%. Since we have 3 DC chargers in Portland area I will try only to use those and not the L2s.

If the utilities want EVs to take off they could allow private companies to put a $10000 DC charger at every substation. If the station service transformer has enough capacity and can handle the extra 50kW load then it will only cost up to $2000 for a breaker, meter and a conduit.

And the utilities in California should forget about that peak charge. You help them by charging at night, they should wave the over 20kW charge. Use a card system in conjunction with your home charger: you charged last night off peak hours you get a cheaper rate next day at QC. If only they are really willing to help!

 

[EVDRIVER]

Public L2 can only be a temporary solution until the EV number increases. What are we going to do, have L2 charger at every parking spot? Keep half of the parking around the store entrances for EVs?

In my opinion L2 is a waste of public money if they are not next to a quick charger for charging above 90%. Since we have 3 DC chargers in Portland area I will try only to use those and not the L2s.

If the utilities want EVs to take off they could allow private companies to put a $10000 DC charger at every substation. If the station service transformer has enough capacity and can handle the extra 50kW load then it will only cost up to $2000 for a breaker, meter and a conduit.

And the utilities in California should forget about that peak charge. You help them by charging at night, they should wave the over 20kW charge. Use a card system in conjunction with your home charger: you charged last night off peak hours you get a cheaper rate next day at QC. If only they are really willing to help!

$2000 to install a 50KW L3 station? Does that come with a unicorn? L1 is the best bang for the very low buck in most cases as many people that commute sit at work for eight hours and have no need for L2. It is not to expensive to do this in many parking spots.

 

[DaveinOlyWA]

regen efficiency is....

oh thats right. no one really knows. but its between 25 and 75% (i believe is the guesstimated range?) and even if it was 75%, which its not, any other charging method is much more efficient AND CHEAPER.

try pricing one of those dynama...thingys.

i see a half dozen options for EV's future. all of which will have a role.

Quick Charging,

large #'s of L1/L2 EV charging (i envision legislation requiring a certain percentage of all new parking to have a charging station. i am hoping AT LEAST 10%. but 25% is what we need)

battery swap stations; Better Place has a great idea and i believe they will be successful.

once again, all these options will be available. GM is developing a pad that does not require plugging in. simply park and charging starts automatically based on your settings (iow, dont charge unless SOC is less than 80% as an example)

now, in a pinch. i would not be beyond rolling down a big hill if one was close enough to push to or "turtle it" there.

one quick thought; not sure that regen is designed to run at high rate for extended periods of time. i have done a few hills where i was in regen in the 10-20 kw range for 5+ minutes and everything seemed ok. but at 30 kw for 10+ minutes?? not sure i would want to risk it

 

[camasleaf]

$2000 to install a 50KW L3 station? Does that come with a unicorn? L1 is the best bang for the very low buck in most cases as many people that commute sit at work for eight hours and have no need for L2. It is not to expensive to do this in many parking spots.

What do you think it will be cheaper 40 outlets across the parking lot and to reserve those parking spots for EVs? Or one parking spot with a $10000 quick charger when the power source is available within 100 feet. Plus this parking spot can be on the driveway next to the substation gate, where real estate cannot be that expensive. When enough EV are parked for 8 hours, the demand will be similar for 40 L1s as for one 50kW QC.

I am sorry public L1 and L2 (slow charging) do not make sense to me in the long term. They are OK for now while the number of EVs is limited.

 

[DaveinOlyWA]

I am sorry public L1 and L2 (slow charging) do not make sense to me in the long term. They are OK for now while the number of EVs is limited.

no matter what? hmm, lets examine that. unless you are taking a long trip, on average your car sits about 22 hours a day. suppose you have "errand day" and it only sits 20 hours a day (you would be in the ½ percentile range) that means 20 hours of charging.

now, if you ONLY charged at L1, you would be getting back about 5 miles or about 100 miles. add to that another 100 miles you already had and you now must average 50 mph during your drive time.

right now, we say that L1/L2 charging does not work because we have to plan for that. charging is simply too far, too inconvenient, too full, or simply not there.

put a charger EVERY where and we will not have this issue any more. you would literally be getting in your Leaf with most of your range left (i would probably be on a permanent 80% setting)

now i know you are thinking; too much money. how long is this going to take? etc.

well tell me something. how well do you think gas cars would work if there were no gas stations? or if there were only a dozen or so and the wait time was 20-30 minutes to get gas?

do you think that just because you would only have to do this once a week that it would be acceptable? no of course not and neither is the current EV charging situation. but that will change. it will change because we want it. its no longer lip service like the EV 1 fiasco. it will soon be nationwide.

it will be impossible to quash like the EV 1. GM had it easy. it only had to lobby a single state to get rid of the EV1. well we learned. GM or anyone else hasnt got a prayer in Hell of stopping EVs now.

only we can stop it. stop it by complaining. not thinking outside the box. not figuring out how EVs can work for us. sure, it will take an effort. talking, asking, lobbying, etc. but EVs aint going away and crying about what you cant do right now is only making it worse. it just takes attention away from viable solutions and L1/L2 is a viable solution. it will not work for everyone but it will work for a lot of them and what that does is take a few thousand voices and makes it several thousand voices who will ask for more and more and more and more needs will be met and so on and so on.

 

[camasleaf]

A very large number of L1/L2 will take decades to install and will be costly. By the time we are done installing outlets on all the parking lots, the battery technology should improve making them obsolete. It will be easy to remove one 50KW charger and replace it with a 100kW charger.

 

[DaveinOlyWA]

but that is one charger charging one car at a time. if you could manage it that would be 2 cars an hour so we could charge no more than 16 cars a day? my employer has nearly 1000 in my location alone. that makes a pretty small percentage. if the 650 (yes we have a parking issue!!) spaces were equipped with 10% EV charging that would be 65 people charging up.

120 volt charging installs are relatively cheap. allow me to swipe my RFID badge (which i need to get into the building anyway) and have it deduct the power i use from my paycheck. or allow me a certain allowance (they already provide HUGE discounts for bus passes) per month for charging and bill me for the excess if i get any. keep in mind, every year my company hands out free bus passes for all kinds of stuff. they pay a certain percentage towards vanpools etc (or at least they used to...)

as far as expense. putting something into an existing structure is expensive. simply designing it into new construction i have to say is probably a nominal expense at best.

the City of Lacey has 120 volt plugs lining the sidewalks in its downtown corridor. they are not in a position where cars can plug in though since there is no on street parking. they are used for random events and electric devices like leaf blowers, trimmers, etc. they are simply 120 volt GCFI plugs sticking out of the sidewalk near light poles every 20 feet and they are all over town.

i know Lacey did not spend a bundle on them (they dont have a bundle to spend) so if they are that easy, then why not?

heck i have a pix here somewhere...

 

[EVDRIVER]

A very large number of L1/L2 will take decades to install and will be costly. By the time we are done installing outlets on all the parking lots, the battery technology should improve making them obsolete. It will be easy to remove one 50KW charger and replace it with a 100kW charger.

So 100 cars at a Cisco lot will all wait in line for your one charger that would require about $25kK + (easily) installation for L3 because many locations like detached work parking that have no access to 440. Have you seen some of the bids for L3 installation on locations that already have the needed power? All for about 20-40% charge needed in most cases? Do you know how inexpensive L1 is to do even on a large scale for multiple users in relation to L3? I have already heard the feedback from meetings for many large corporations and they all know L1 is far more effective but many are simply going with fewer L2 stations because they are free (at the moment). As a matter of fact (not speculation) most corporate L2 stations are active for a fraction of the day and sit unused and blocked by charged EVs. A single station at the workplace where the vast charging is needed, is simply an added luxury to L1 and some L2. I suppose companies could hire a valet and get a sign in sheet. I suppose Google should just go to a single L3 solution, they already have the infrastructure and the money to do it right now. I can't wait to see the contingency plan when a single L3 station goes down.

By the way, even with new pack tech power in is power in and that equals miles out. If pack sizes are larger then people need less charge to commute home. Pack tech is not relevant to the small fraction of charge most need in commuting situations.

 

[DaveinOlyWA]

ok... "some" info to report. my electrician friend who is a bit unwilling to commit states that power requirements alone would be minimal cost. could cost as little as $3000 for 10 L1 spaces for single service connection for residential.

he also states site work will add several thousand and that permits, taxes, etc vary as much as 30% from area to area.

but he states that providing several dozen L1 charging sites would in most cases, require NO ELECTRICAL SYSTEM upgrades for most businesses.