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[pacificcricket]

The possibilities are more or less endless in how you want to rig it. The blanket should work but you could also just lay it on the ground.

This thread reminds me of a solar moped that has been on the internet for ages:

I did some testing with a 100W panel I have. In mid Summer, around noon, I am getting about 86W when it's correctly pointed to the South at 30 degrees. When
laid flat, output goes to about 69-70W. This is in Portland, Oregon btw.

[Starpower]

Another solar eng. here with 40 years exp. If you're going to do the 6-9 module route then don't make a dedicated to bike charger but instead do a grid-tie and continue to charge off of 120Vac. This has multiple advantages - you can get by with far less PV wattage as it will accumulate power and credit your utility account on days when not charging. Also, when you're fully charged the PV continues to contribute to your needs or making credits. Also, go with much cheaper higher wattage modules of 260-345W that are typically used for grid connect systems, you could see 1/2 price per watt.

I live off-grid with a stand-alone battery based system (12V at 18kWh) I just added another 945W of PV to my system for a total of 4.4kW of PV. I can do a full recharge  for my Zero in 1-2 days with just my surplus power without tapping my home batteries.

If one must for some reason desire a PV to bike direct then I would inquire with Zero or the charger manu if your charger can take ~120Vdc input as many AC-DC chargers can, this gets around regulation issues however, I would be very concerned about "brown outs" from passing clouds giving the charger fits.

[pacificcricket]

If one must for some reason desire

The reason being to charge while away from home, such as when camping I also have a 2.16kW grid-tied system at home, no need to invent the wheel there.

[Shadow]

Okay say you don't get any real range extension, can you effectively use the bike's battery pack as a power source and replenish the power you use?

[KrazyEd]

   I am presently ( mostly ) running my 1800 sq ft home on a 4K solar panel system jerry-rigged with 24K battery pack ( 16 ten year old 12v 125 ah agm batteries ),
a 2K pure sine inverter and a 3500 modified sine inverter. The solar runs parallel to the grid with no interaction between the two systems. If it is cloudy more than
a day or two, I unplug from the inverters and back into the grid. I know that there are inverters with auto switching, but as I am not an electrition, and am doing
this mostly myself with advice from the internet, this is the way that works for me. I converted my 240v water heater to 120v. I have DC elements for the water heater but, have
not yet put them in to go direct from batteries to water heater.  I ended up with this set up last year after the Public Utilities Commission decided to screw the
residents of Nevada. ( Long story, not pertinent to this thread ). I charge my electric vehicles around town and use the batteries to top them off if necessary at home.
   The most efficient way to charge a Zero would probably be straight DC but, this would be more complicated and potentially more dangerous. The simple way would be to use
batteries and inverter.  With DC to DC, you go directly to the battery pack with dc voltage. If you go with an inverter, panels go to batteries, batteries go to inverter,
stock charger plugs into inverter. It sounds more complicated but, nothing has to be modified on the Zero for this path.
If the charger is 80% efficient, you would need to produce around 16 KW to charge a Zero 13. There is also loss due to conversion.
DC to AC to DC. Your total output would probably need to be in the 20 KW range. A 4KW system with 5 hours of daylight should meet this need.
   Be careful if deciding to go with a Net Metering Grid Tie arrangement. Many municipalities around the country are working on scrapping those agreements or
making them cost prohibitive by way of various fees. A Dedicated 4K system just for charging might be a better route, but, still probably not cost effective.
If going full solar, just add extra panels ( If allowable ) ( not allowed in NV ). Extra panels are easily added after the fact but more cost effective if done all at once.
Sorry for rambling.

[Shadow]

I got a reply from PowerFilm and they say as a rule they do not market any panel with a voltage over 30VDC for safety reasons. Higher voltage panel layouts are possible to produce but they would have to be sold without any electrical terminations.

That makes sense if you grab the wrong bit and the panel is rolled out it could be a nasty surprise / shock.

Also I got a reply from Genasun makers of small scale MPPT boost-capable charge controllers. Their blunt answer is yes it's a total waste of time to make a portable PV system that puts energy into a high voltage DC battery system. Anyways it was suggested that a separate 12VDC battery system to hold power for camping would be a better plan.

What is the best way to get power out of a ZF13.0 battery?   Should I have the bike on and run an inverter from the DC-DC converter?   Could I safely access power out of the AUX charging port?

[pacificcricket]

I got a reply from PowerFilm and they say as a rule they do not market any panel with a voltage over 30VDC for safety reasons.

I am preparing for getting a ham license (technician), and the study guide lists 30V as the smallest potentially deadly voltage.
So that kind of makes sense. Most panels seem to be intended to be connected in series anyway, as DC-AC conversion is more efficient when input DC voltage is close to output AC voltage.

Also I got a reply from Genasun makers of small scale MPPT boost-capable charge controllers. Their blunt answer is yes it's a total waste of time to make a portable PV system that puts energy into a high voltage DC battery system.

It is also a waste of time to make an electric motorcycle, why can't people just use gasoline ? These guys simply aren't
on the same page, and don't understand the use case.

Do we need an MPPT boost-capable charge controller, or we can get away with something simpler, like a voltage regulator of sorts ? Basically if the solar output drops beyond certain point, just cut it out completely, instead of trying to compensate.

[wontuan]

I don't want to tell you that you can't do something but let me explain why Genasun said it's a waste of your time to make a portable PV charging system for a Zero.
The current state of solar technology just can't produce the power to charge a Zero in a reasonable amount of time (2-3 days) and be portable and small. I know the argument here is that the technology will get better and that some day we will have panels that can supply so much power. This is true,  panels will get better, but they will never get to the power level you need. The highest consumer solar cells right now are like 22% efficiency (SunPower and SolarCity cells, not counting space-space solar tech) and there are some gallium arsenide cells that approach 32% efficiency and they will get better but even at 100% efficiency it still won't be enough. This is because there is only about 1kw/m² of solar power hitting the earth's surface, this is what people mean when they say an irradiance of "1 Sun". There are some high altitude areas where I have seen 1.2 Sun (1200kw/m²). So if you had a solar panel that rolled out to be a meter squared and had 100% efficiency (not possible btw look up Shockley–Queisser limit) you would only generate 1kwh every hour ( assuming 100% efficiency in wiring, charger, module glass, and DC-DC converter). There are only 2-3 hours in the day where you would get peak power so you would generate maybe a max of 4kwh a day. So to charge a ZF9.8 you would need a little more than two days using the 100% square meter of PV and both days would have to be fair sunny. By the time we get this 100% efficient panels battery tech will have advanced so far that you may not need to charge at all. If you still want to pursue this portable camping PV charger let me know if you make any break through because if you can generate more than 1Kw/m² using PV I would like to invest in whatever company you plan to start.

I think your time and money is better spent on getting a fast charger and using the RV plugs at camp sites to charge. This is something I do and it works great. I just find an RV 14-50 socket and then in an hour I am almost full on my ZF9.8.

[Erasmo]

I don't want to tell you that you can't do something but let me explain why Genasun said it's a waste of your time to make a portable PV charging system for a Zero.

As is crossing the continent on an electric motorcycle It would be cool to be the first to do it on solar that you bring along.

[BrianTRice@gmail.com]

I don't want to tell you that you can't do something but let me explain why Genasun said it's a waste of your time to make a portable PV charging system for a Zero.

As is crossing the continent on an electric motorcycle It would be cool to be the first to do it on solar that you bring along.

What an inappropriate comparison! The speed of travel implied by solar rates here means you'd probably travel faster on a bicycle and even save money.

[Lenny]

There's a german dealer who has a solar system running, but they use a bi-directional inverter attached to the aux port and apply voltage to the small aux contact to close the contactor. The inverter also features things like over-/undervoltage protection and more. It is programmed to a certain voltage and individual charge curves depending on the type of the battery attached.

The idea in this case is to make use of the Zero as a home storage in times when you're not using it, which at least in Germany is a major part of the year. Don't want to start a discussion here whether that makes sense or not, but it seems to work quite well.

[Shadow]

@Lenny sounds good, do you have more information where to buy or how to build?

[Erasmo]

I don't want to tell you that you can't do something but let me explain why Genasun said it's a waste of your time to make a portable PV charging system for a Zero.

As is crossing the continent on an electric motorcycle It would be cool to be the first to do it on solar that you bring along.

What an inappropriate comparison! The speed of travel implied by solar rates here means you'd probably travel faster on a bicycle and even save money.

If I wanted to travel cheap and fast coast to coast I'd just buy a plane ticket. This is more of a because you can scenario, pushing the envelope while having an adventure.

For example, lets take a look at the route of the World Solar Challenge:


Most of those legs are around 300km, with one that is 440. A full streamlined electric motorcycle should be able to do that in one charge. A Zero would be actually ridiculously overpowered to do this, IIRC most solar racers have only a 1500W motor.

But let's say you take a 8kW motor, more than enough to drive at normal road speed. You do have the sun in your back which isn't optimal but with smart placement you should be able to get 200W continuous(this is a rough eyeballed amount) while driving in good daylight and the tail has more than enough place to store 1-2kW flat panels that you can use with a proper DC-DC inverter to charge via the aux port.

Will it be cheap? No. Will it be easy? No. Will it be a cool adventure? Definitely.

[Testpilot1]

Saw this on YouTube and thought of this thread

https://m.youtube.com/#/watch?v=b9_xXY7Ez7A

Is this possible ?

[Erasmo]

Yes, but it will take a looong time with only one panel.