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[Ittindi]

Don't listen to the naysayers.  This could be the beginning of adventure electric biking.

[protomech]

Adventure electric biking @ 6-10 miles per day. Not going to happen with onboard solar, at least on anything resembling a conventional motorcycle or being operated at conventional motorcycle speeds.

2013 Zero needs 10 kW to operate at 70 mph, 6.5 kW to operate at 55 mph. Onboard solar produces .. at best .. 200 W. Our power requirements are about 50x what the onboard solar can provide.

Solution:
1. Increase solar power. More efficient panels or just more panels.
2. Decrease power requirements. Huge aero improvements (solar racers) or just slow down.

These guys claim 200 miles/day with a custom tandem-seat recumbent pulling a solar trailer (23 foot bike + trailerlength).
http://solarbikeproject.com/TechSpecs.html

They claim 30 Wh/mile - 50 Wh/mile @ 20 mph (depending on level of pedal input) - or about 600 - 1000W. Basically the same energy used as our Zeros, despite weighing much more. They have 1000W of solar onboard.

[Ittindi]

Except that the point of this thread is to stop and set up the solar array so it charges the battery while the OP is at work.  Or, in other words, while the rider is off doing something else, like exploring.  Not to mention the benefits of having an alternate energy source to combat running out of energy miles away from a recharge station.  [ ] <~~~~ Think out of it.

[protomech]

Ah. I misunderstood "adventure electric biking" as adventures on a bike, not adventures off a bike.

[WindRider]

Well, this is pretty simple math.

If you want to charge a 2012 Zero you need to make more than 1KW to charge at it's normal rate.   So you need about 1200 W of solar panels.   With current solar technology this is about 5 panels that are about 3 feet by 5 feet so a total of about 75 square feet of solar collector to match the current AC charger's charge rate.

It would make a nice little parking shade, but portable it is not.   It could done as a standalone shelter that you park under and plug in to.   It would cost about $1500 - $2000 for the panels and then more for the structure and whatever kind of electronics you wanted to use to get the juice into the bike.

Anything less than 1KW of generation would mean multiple days to recharge from empty to full.

[NoiseBoy]

Actually your calculations are flawed.  PV cells are DC so you arent going to use the onboard charger, that would be silly and inefficient given that by the time you had converted to AC you probably lose 10+% and then the charger back to DC is lossy again.  You probably need more like 800W of generation.  BUt bare in mind that Solar isnt guaranteed so you would more than likely need 2 or 3 times that amount to be certain of a charge on a cloudy day.

You are right that a portable system to recharge at normal rate is impractical, but that doesnt mean that charging at a lower rate isn't worthwhile.

[DesignerDan]

The bike doesn't need to charge all the way. I use one bar getting to work. So I'm looking to charge for 8 hours just to replenish that bar. It should be doable with a portable system. The only thing I'm worried about is over charging. I don't feel comfortable hooking a dc dc boost directly to the battery. I need a failsafe or a way for it to shut don't when the battery is full.

[protomech]

One possibility would be to run the battery down to 50% or so, then charge direct DC during the week, do a grid balance over the weekend.

A custom charge controller could charge the battery safely and terminate the charge at say 4.1 volts per cell. (I say safely.. I don't know how the battery would respond to intermittent charging, but I assume this would be fine)

1 bar on a 2013 = roughly 800 Wh, 8 Ah. Two bars (for round trip) = 16 Ah (~1.6 kWh).

If you get 4 hours from solar over the entire day, then you need about 4A @ say 110V .. about 2x what you have now.

Powerfilm has a number of different thin film solar panels. Their 60W panel is 15.4V 3.6A, weighs about 3.2 pounds.

8 panels in series would give 123V (open circuit?), which is in the right ballpark to charge the 2013 battery. Total weight would be 25 pounds of thin film photovoltaics, call it 30 pounds with cables and electronics.

Total area required would be around 8' x 16'. And you'd have $6k in thin film PV just laying out on the ground. Perhaps not super-practical..

[Biff]

Actually your calculations are flawed.  PV cells are DC so you arent going to use the onboard charger, that would be silly and inefficient given that by the time you had converted to AC you probably lose 10+% and then the charger back to DC is lossy again.  You probably need more like 800W of generation.  BUt bare in mind that Solar isnt guaranteed so you would more than likely need 2 or 3 times that amount to be certain of a charge on a cloudy day.

You are right that a portable system to recharge at normal rate is impractical, but that doesnt mean that charging at a lower rate isn't worthwhile.

I think you may have missed my earlier post.  There are many battery chargers that work from AC power or DC input. http://www.meanwelldirect.co.uk/products/120W-Single-Output-IP65-Rated-LED-Lighting-Power-Supply/HLG-120---A-Series/default.htm  Since the first stage of these chargers is AC/DC, you can input DC and they work just fine, so you don't need to go from DC solar to AC power back to DC in the battery. The Mean Well that I linked works that way, you just need to have 127V-370V DC input. That would require minimum 230 silicon solar cells in series which wouldn't be too bad for a home installation, but for a portable array is not feasible.  Assuming a cell is about 2W, you would probably find a 500W panel that outputs more than 120V DC, then charge directly from that without having to convert from DC  to AC back to DC, and save yourself from having to buy a large inverter as well.

One thing that is neat (but not related to solar panels) is that with these chargers you can plug directly into the High Voltage battery of a Prius (or other car that has a 127 - 370V battery) and charge directly from that. The Car will start up and idle act as a nice and quiet generator if the car's battery gets low while your bike charges .  The Prius makes for a great electric bicycle or motorcycle , race / road trip vehicle if you have a charger that can run off its battery, because you don't have to pack a generator, or rely on sketchy track or back-woods motel power, and they are good on gas and very capable of pulling a light weight motorcycle trailer.

Someone might want to take a look and see the manufacturer / part number of the on-board chargers on their Zero, and see what they can actually use to power it.

-ryan

[DesignerDan]

Actually your calculations are flawed.  PV cells are DC so you arent going to use the onboard charger, that would be silly and inefficient given that by the time you had converted to AC you probably lose 10+% and then the charger back to DC is lossy again.  You probably need more like 800W of generation.  BUt bare in mind that Solar isnt guaranteed so you would more than likely need 2 or 3 times that amount to be certain of a charge on a cloudy day.

You are right that a portable system to recharge at normal rate is impractical, but that doesnt mean that charging at a lower rate isn't worthwhile.

I think you may have missed my earlier post.  There are many battery chargers that work from AC power or DC input. http://www.meanwelldirect.co.uk/products/120W-Single-Output-IP65-Rated-LED-Lighting-Power-Supply/HLG-120---A-Series/default.htm  Since the first stage of these chargers is AC/DC, you can input DC and they work just fine, so you don't need to go from DC solar to AC power back to DC in the battery. The Mean Well that I linked works that way, you just need to have 127V-370V DC input. That would require minimum 230 silicon solar cells in series which wouldn't be too bad for a home installation, but for a portable array is not feasible.  Assuming a cell is about 2W, you would probably find a 500W panel that outputs more than 120V DC, then charge directly from that without having to convert from DC  to AC back to DC, and save yourself from having to buy a large inverter as well.

One thing that is neat (but not related to solar panels) is that with these chargers you can plug directly into the High Voltage battery of a Prius (or other car that has a 127 - 370V battery) and charge directly from that. The Car will start up and idle act as a nice and quiet generator if the car's battery gets low while your bike charges .  The Prius makes for a great electric bicycle or motorcycle , race / road trip vehicle if you have a charger that can run off its battery, because you don't have to pack a generator, or rely on sketchy track or back-woods motel power, and they are good on gas and very capable of pulling a light weight motorcycle trailer.

Someone might want to take a look and see the manufacturer / part number of the on-board chargers on their Zero, and see what they can actually use to power it.

-ryan

It looks like the output only goes up to 54 volts? I've been having trouble finding low wattage/ high voltage chargers.

If I could find such a charger I guess I could use a dc dc boost to feed the charger. I will lose some efficiency running it through a boost and a charger but that seems like the safest way to do it. If I hook both of my arrays up in series Ill have 40 volts. 

[protomech]

Prius as a generator for the Zero is a pretty great idea.

I think that from what i have read recently Zero 2013 have integrated charger made of 4x 320Watts  Meanwell HLG-320H Led power supply with adjustable current and voltage limit. i think its 2s2p ( 2 parallel  time 2 connected in serie) These accept from 100Vac to 305V ac.

http://www.meanwell.com/search/hlg-320h/default.htm

DOc

You could just run two chargers in series like Zero does.

[Richard230]

Two years ago I was camping at a state park and noticed a fellow sitting in his Prius with the engine idling.  Two hours later he was still sitting there idling.  So I went up to him and asked what was going on.  He told me that he was charging his cell phone and didn't want to run his car battery down.   

[NoiseBoy]

Two years ago I was camping at a state park and noticed a fellow sitting in his Prius with the engine idling.  Two hours later he was still sitting there idling.  So I went up to him and asked what was going on.  He told me that he was charging his cell phone and didn't want to run his car battery down.   

I really struggle to believe that someone would be that stupid.  Terrifying that somebody thick as two short planks is allowed to drive 1.5 tons of metal around at 70mph isnt it.

[mr1396]

Would the Goal Zero yeti 1250 solar kit work for charging the zero fx 5.7?

[protomech]

According to the specs, yes. I had some problems charging my Zero S from a solar inverter, but that was probably not a sufficiently large inverter.

The Yeti 1250 should give the FX ZF5.7 about a 20% charge in 90 minutes before the Yeti needs to be recharged itself.