4x170W panels 30Vmp to power a ebike?

[rollandelliott]

I want to make a solar powered ebike and I am trying to find a MPPT controller to do it. Most ebikes use one GenaSun mppt unit per panel, but they are about $200 each or $800 for 4 panels. I am trying to find something cheaper. the flexible sunpower solar panels will be abot 4' wide and 2.5' long or 4' x 10' all together. they will fold for storage. 2s2p configuration to get 60v going to the KID MPPT.

Basically I want the solar energy to go directly into the motor controller that powers the 700w hub motor and if there is any excess energy I want it to charge a 48v battery.  This is how most of the university solar cars work I think and it avoids the loss in efficiency when going into a battery. 

when the vechicle is parked I would want all the PV energy to go into the battery.

Would the midnite solar KID work for this application?

[ClassicCrazy]

The place to do some research and probably find someone who has already done this kind of project is on Endless Sphere forums or the facebook group.
https://endless-sphere.com/forums/
I can't answer your question about the Kid in this application.
I found some info on those type panels online rated at 175 watts per panel.
The thing is you won't get full power out of them unless ideal conditions . Your 700 watt motor is going to need the battery all the time. 
Not sure what those other controllers do if they are able to run the motor without a battery involved then where must be some other electronics.
If you had a controller like the Kid it would supply all the power available to a battery below certain set points but it isn't designed to run direct to a load especially one like a motor that has surges .
And then when you mix in Lithium batteries that has its own specific charging and discharging needs it gets more complicated with internal BMS etc.

Larry

[rollandelliott]

I've looked at the endless sphere forums. and there is not much information.
there is a solar racing group on reddit, and they recommend some $1200 Mppt's from Europe or Austarlia. Their cars' cost halof a million to a million dollars, lol.

I've seen youtube videos of solar bikes without batteries, sure they are not as efficient but it is easily done since most motor controllers have a broad range of input voltage about 36-70v.

The spec sheet says Load Terminal 30A Configurable as battery load or wind clipper
And these 4 solar panels only output 60v at 12amps so maybe I won't be able to go up a steep hill, but on regular ground should work.

Which has me wondering do I even need a MPPT? If i use a nominal 52v lion battery pack then the 60v from the panels should charge it up fine right??? if it's cloud and the voltage drops a lot is the main benefit right? it will boost it up to 60v? Just wonder how cloud and how low of a voltage it will work with.

[ClassicCrazy]

I just went to Endless Sphere forums and did search for solar powered ebike and I found lots of
projects and discussions.
Larry

[rollandelliott]

yes and 99% of them dont' involve MPPT controllers that can handle 8amps at 60v,  they involve genasun or cheaper controllers that can only handle about 150w.
there is a huge difference between a 4 name brand panels vs one or 2 cheap chinese ones with poor output.

[ClassicCrazy]

seems like if you get the pv positioned properly for peak power on an ebike during certain times of the day you would make a huge wind load that could work with you as a sail or very much against you . 

Larry

[rollandelliott]

https://youtu.be/QfXBNfKF5Sc?t=2913
these are the $1200 mppt's used in solar cars. it's $300 worth of parts and then $900 worth of profit for the manufacturers. They can charge high prices I guess because so few people buy them.   Their claim to fame is allowing the solar to directly power the car when the battery is full. and only charging the battery when needed.