JoeS
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Location: Los Altos Hills, California

Re: solar on the car roof

Thu Sep 20, 2012 2:29 pm

Davide never plugs in this lithium-powered Sparrow - all the panels fold up into a package as a front bumper:

Image
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

PV1
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Location: Pittsburgh, PA
Contact: Website

Re: solar on the car roof

Thu Sep 20, 2012 3:25 pm

Help it! It's getting attacked by a Prius! ;) Pretty neat setup it has, though.

I was reading on pluginamerica.com and it showed an extended range battery pack for the LEAF that fits in the floor of the trunk. It has its own charger that grabs some juice from the J1772 plug, and feeds in battery power on the DC side of the onboard charger. Could something like this be done for the i? Possibly have it connect on the high voltage side of the dc-dc converter, so power input/output looks like the 12 volt system to the car? Use a PV controller with boost for 330 volt and charge this battery with solar, that way there's extended range and solar power available while driving. If the dc-dc converter is on while the car is plugged in (meaning HV available because of a closed contactor), a second contactor could be installed for the second battery and close with the dc-dc contactor, so both batteries charge on plug-in with power going to the second battery looking like 12 volt usage to the car.

Here's the link to the LEAF's battery:
http://www.pluginamerica.org/accessorie ... ttery-pack
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
Solar-powered since 10/10/2013

"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015

2017 Bolt EV LT in Orange with QC - 7/31/2017

Driving electric since 2-21-2013.

JoeS
Site Moderator
Posts: 3381
Joined: Thu Dec 15, 2011 5:47 am
Location: Los Altos Hills, California

Re: solar on the car roof

Thu Sep 20, 2012 6:02 pm

Hey, PV1, have you bought your iMiEV yet?

At the Green Drive Expo there were two companies showing off their add-on plug-in battery packs for hybrids. Same concept certainly applies to EVs. Enginer's is a 48v pack feeding a dc-dc converter feeding the HV traction pack. Plug-In Supply's output voltage matches the vehicle's traction pack.

If this output is properly current-limited and diode-isolated and fed in at the motor controller battery connection while the battery pack and the vehicle are both turned on, I think that the iMiEV's BMS would simply treat this it like regeneration. No technical reason why this shouldn't work that I can think of. As well as plugging it in, one can recharge the auxiliary pack using solar.

Is the concept of an integrated onboard solar-recharged auxiliary battery pack time, cost, volume, and weight effective for our little iMiEV? You can do that analysis yourself, if you wish.
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

PV1
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Location: Pittsburgh, PA
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Re: solar on the car roof

Fri Sep 21, 2012 8:43 am

Nope, not yet, but getting closer every week. I'm looking mid-March.

I priced cells to match the traction pack voltage and store 20 Ah. It was about $3,000 with BMS and connectors. The solar is another $1,000, but I'd need to find a dc-dc converter to get to traction voltage.

As to how the car treats the extra electrons, that's why I thought to put it on the 12 volt converter circuit so the pack is only connected during driving and charging, and so that the power is accounted for. I guess the controller input would work, too. You just can't hook it directly to the traction pack terminals or else coulomb counting and SOC reports would be seriously miscalibrated. It has to be metered by the car somewhere, and that's where the motor controller or converter come into play.

I remember seeing a solar-powered Prius that had the same setup we're talking about. It treated the power as regen. Greg Johanson made it.
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
Solar-powered since 10/10/2013

"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015

2017 Bolt EV LT in Orange with QC - 7/31/2017

Driving electric since 2-21-2013.

JoeS
Site Moderator
Posts: 3381
Joined: Thu Dec 15, 2011 5:47 am
Location: Los Altos Hills, California

Re: solar on the car roof

Tue Apr 02, 2013 12:07 pm

Hey, PV1, for a long time you were concerned about charging at work. Here's a solution: :geek:
http://www.greencarreports.com/news/1083312_lotus-mobile-a-portable-affordable-solar-charging-solution
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

PV1
Site Moderator
Posts: 2899
Joined: Fri Apr 27, 2012 4:22 pm
Location: Pittsburgh, PA
Contact: Website

Re: solar on the car roof

Tue Apr 02, 2013 2:28 pm

Reminds me of Icarus:

Image

And the man behind it:

Image

(Elon Musk's unknown twin)


If anybody remembers way back when I was talking about a 73 mile commute without any destination charging at the apprenticeship (wasn't this thread), I swung by the place when I first got the car a little over a month ago. They now have a solar canopy with two level 2 chargers. I just come from a level 2 charger a few miles up the road when I stopped, so I was pretty close to full in this picture. The chargers had card readers on them anyways.

Image
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
Solar-powered since 10/10/2013

"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015

2017 Bolt EV LT in Orange with QC - 7/31/2017

Driving electric since 2-21-2013.

JoeS
Site Moderator
Posts: 3381
Joined: Thu Dec 15, 2011 5:47 am
Location: Los Altos Hills, California

Re: solar on the car roof

Fri Dec 05, 2014 12:05 pm

PV1 has a penchant for solar-powering vehicles, so I thought I'd continue adding to this thread with this article on a solar4-powered VW bus conversion. Unfortunately, it's lacking in technical details…

http://www.bostonmagazine.com/news/blog/2014/11/14/vecna-cto-solar-powered-vw-bus/

Sorry, don't know how to reduce the image size for this photo linked directly to that site:

Image
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

Don
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Joined: Thu May 10, 2012 3:55 pm
Location: Biloxi MS

Re: solar on the car roof

Sat Dec 06, 2014 10:49 am

Neat!

On a (semi) related note, I recently read that a 1955 23 window micro-bus with 6,500 original miles on it sold at auction in Germany for $235,000. They made hundreds of thousands of them but due to rust and hard use, originals in good condition have become quite rare and evidently very valuable!

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

LMT
Posts: 2
Joined: Thu Mar 09, 2017 4:08 am
Location: Adelaide Australia

Re: solar on the car roof

Fri Mar 24, 2017 6:43 pm

Hi all,

Just got my i :D 2010 model and looking for solar hack to charge main pack. Ive read and searched alot of the posts but coundnt find anything on how the regenerative braking system works, which is where i hope to add solar/battery input. are there any wiring diagrams of how it works?

I can only assume that when regen braking occurs thru D, E or B (love driving all the time in B and saving brake pads) the engine produces a DC output (anyone know the voltages and currents generated?) which is then returned/applied some how to the traction battery pack .

my current intention is to have:
solar panel 200+W > battery charger > battery > power diode > connection to regen system.
so battery chargers during day light hours and adds to regen when braking occurs in D, E or B.

i understand even if i can get it to work ill only be getting a couple of km extra a day but i think thats cool.

Cheers

Don
Site Moderator
Posts: 2576
Joined: Thu May 10, 2012 3:55 pm
Location: Biloxi MS

Re: solar on the car roof

Sat Mar 25, 2017 9:08 am

Max regen is on the order of 340 volts and 75 amps. You would need a BUNCH of very tiny solar cells to get you the needed 340 volts . . . . at 2.5 volts per cell, around 130 or 140 of them and they would be so small they probably wouldn't give you half an amp. As you've no doubt read, solar on the car roof is completely impractical. If the solar panels added to the Cd by even 5% or so, it would probably be a net loss - You'd lose more range by increasing the drag than you would gain

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

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