Solar powered electric chopper bike

[Nate D]

Ok, the build is finaly complete. This is a "stilletto" chopper bike 5 speed made by Giant. It has a brushless hub motor conversion done to it and runs on a 36 volt battery pack. I made a modular solar panel array of 36+ volts and 10 watts which is wired in to charge the battery pack using the power of the sun. Torque and speed is great hits about 18 to 20mph and gets there fast. Plus I think it looks great. The solar panel set up can quickly be taken apart and put in a back pack if needed and the battery can be charged using a charger on days with no sun, not to mention you can always pedal as well. Hope you guys like it I will be riding this a lot here in Auburn WA area when the sun is out.

 

[jrol22]

Looks like something "Doc" from Back To The Future woulda made! NICE job!

 

[zabac70]

Very nice bike! I like solar stuff , because they are green and pretty much universal (you can charge mobile phone , flash lights lap top...). One concern tough , does it "pulls" to the right , because you hanged all the stuff on one side?

 

[deacon]

I think I would have gone for the solar panel at home and two battery packs. I know cheapskate me, but that looks like a damaged solar panel waiting to happen. Not just from being hit in the parking lot, but the vibrations of running the bike would terrify me. Every pothole would be my enemy.

 

[OzzyU812]

a few years ago i lived in Auburn WA!

very nice!
deacon has a valid point i'd be nervous about that.
Do fold up when riding? can they go from dead to full charge in 8hrs? assuming a perfect sunny day. i guess the Batt's are SLA?

 

[Nate D]

Great questions guys. First of all I do actually have a solar panel set up at home and 2 batteries! I run a few appliance at home from solar power and can charge the bike battery so it is truly green (power not coming from coal or nuclear power plant) The only thing is the SLA battery packs are extremely heavy so I never actually ride carrying the spare battery. I did some experimenting with the middle solar panel in the pic and it alone would charge the batteries in about 6 hours which is not bad. I then decided to add 2 more rigid ones on the outside and the flexible one in the middle. Vibration is solved by having the panel mounted on a flexible mount which can flex with the bumps. No parking lot accidents, the entire set up can be broken down in 3 minutes and put in my back pack. Wingnuts were used so no tools would be needed to take it apart and stow it away for when I go into work or the store. I plan to commute from Auburn to Kent during nice weather to reduce my gas consumption and save money This was a fun project and it also just get's us thinking of what is possible as far as alternative energy and transportation that is the goal.

 

[Nate D]

One other thing I forgot to mention that was asked by ZABAC70. No the bike does not pull to the right everything is centered that is just the appearance due to the angle of the shot. The solar panel set up weight about 4 pounds so is extremely light. The solar panels work in overcast as well so sunny weather is not really needed, just is ideal. The 2 on the side are rigid 12 volt 2 watt panels and the middle one is a flexible 12 v 6 watt panel. They all ride on aluminum supports attached by a main flex support to counter vibration. This bike rides extremely smooth, no vibration at all it really is fun to ride. I was out today fellas so keep an eye out in Auburn wA and wave if you see me this summer. Here are a few more pics that should clear up any questions ok. Thanks guys.

 

[deacon]

Since I don't work it isn't a problem for me, but I can see this being a great solution for the guy who commutes on the bike. No offense to you at all, I really love the concept, but I think I would have to go with ride without it deployed, then deploy it in the parking lot. I can't build strong enough to trust riding around with it open on anything I built. If I lived in a better neighborhood, I might like a power trailer with that on top. Just leave it on the front porch.

I can even see a day when each battery of the three battery pack would have it's own solar panel as part of the build. Now that would be ideal. Use a light weight battery until it was exhausted, then switch it out while leaving it in the sun till the second one is exhausted on and on.

 

[BossCat]

Thats what I planed to do with my push trailer, once I finish making the box. I have a solar panel that I'll stuck on top to help top up the batteries. Im trying to figure a way to employ my small 180watt scooter motor to charge the batteries but I dont know if this would work? I may need a different type of motor like this treadmill motor?

Self charging home made 24V electric mountain bike.
YouTube - self charging home made 24V electric mountain bike

Nice build bty, but the pics are a little on the small side, hard to see any details. These type of bikes are just crying out to have some type of motor bolted onto them.

Regards
Tom

 

[zabac70]

@BossCat
Do you mean to mount your scooter motor on your bike to recharge batteries? You would be better off with dynamo , but eider way you will be pedaling VERY hard to charge a batteries, unless is big downhill and lots of RPM (look at it as regenerative braking). Motor needs external excitation to work as generator , but the geometry of it isn't very good for imagined purpose (that's why things called generators exists).
BTW , the guy from video clip knows his stuff very well , he got some videos of how to wound (and make) el. motor - I saw it few years ago - and he explains it well and simple (if we disregard the northern British accent - which is , probably , better than mine LOL)

 

[wheelbender6]

It would be cool to unfold your array of solar panels when your reach your destination, like a sattelite, and refold them to resume the ride. Is that what you did on this build?
Perhaps you could do a new post on how to build a solar charger.

 

[Nate D]

It would be cool to unfold your array of solar panels when your reach your destination, like a sattelite, and refold them to resume the ride. Is that what you did on this build?
Perhaps you could do a new post on how to build a solar charger.

A folding design would be very cool especialy if for example i had some kind of locking box so when you get to the store you lock it up. Right now mine does not fold you undo 4 wingnuts and all the alluminum struts and solar panels can be put into you hydration back pack. the middle panel does fold up though the side ones are rigid. I actually wanted the panels to be exposed as I ride. the system is wired so even when the bike is using the battery the panels are wired into the charge port of the pack so they constantly feed the battery energy. Truly though this set up does not take up too much space. It sticks out only 5 inches past the battery on the back and about 5 inches longer on each side. the solar array actually has a slimmer profile than the handle bars! this means it is actually not bulky at all and does not increase the overall profile of the bike. If you can fit your handle bars through somewhere then you are ok...with a few inches to spare. Sure if there is enough interest I could do a write up and take more pics and assist with wiring set ups. I use a 36 volt system.

 

[Nate D]

Here are some better res pics I hope they show more detail.

 

[Nate D]

Well the people have spoken and I have listened! LOL Ok so to further resolve any concerns on vibration or bumps that could possible harm the outer 2 rigid panels I added an oil filled shock obsorber to the rear so now the system is truly a floating suspension type set up. Has about 2 inches of travel and the spring can be adjusted. Can hit bumps worry free. Also listed a pic with the middle panel removed so you can see just how sturdy this is as there were some concerns on that. Enjoy and please feel free to ask any questions or share your story and pic's if you are thinking of doing a solar build as well.

 

[zabac70]

It seems very well constructed. I can't imagine that something would happen to panels , accept (god forbid) some major crash...Unfortunately , where I live , solar panels on a bike would be very inefficient (44 degrees north) , but I plan to find some other use for it (charging stuff).

 

[BossCat]

Sure if there is enough interest I could do a write up and take more pics and assist with wiring set ups. I use a 36 volt system.

I for one wouldn't mind a look at your wiring, just to see how it all fits together, before I try hooking up my solar panel and .... myself

Regards
Tom

 

[Nate D]

I for one wouldn't mind a look at your wiring, just to see how it all fits together, before I try hooking up my solar panel and .... myself

Regards
Tom

Well the wiring looks a little complicated so a pic would not do too much good. What I did was wire my 3 panels in series since I am using a 36v battery. What voltage system were you going to use? This is important as if you are using a 24v system and have 3 panels you must wire 2 in series and the 3rd in parallel. Then I chose to wire them to a connector which matches the same as the original wall charger, tha way the solar panel can be charging the pack while you ride. Here is a pick showing me holding the connector that plugs into the charge port, the 3rd quick connect 2 prong connector below is the one that then connects to the system and makes everything live. I would recommend this kind of set up as it is very useful to be have the system charging at all times even as you ride as this will really extend your range. If you need help and are going to start this project let me know I'll be happy to help just need more info on what kind of setup you want to go with.

 

[BossCat]

Hi Nate,

This is the type of solar panel I have...

12V 4.8W Battery Charger.

Solar-Powered 12V 4.8W Battery Charger - Free Delivery : Solar Battery Chargers : Maplin

I use it on my window ledge at the moment to charge up my battey(s) - one 12V battery at a time. I have 4 other smaller panels I got of ebay a while back for this kind of project but never went ahead with it as I didn't know what size/type of controller to get as im not good with electrics - Volts/Watts/Amps are way over my head.

The plan was to put them on the back of my bike trailer to charge batteries for lights/phone etc Now that I have moved onto an electric bike push trailer I am rethinking solar power again to help charge my batteries while on the move.

http://motorbicycling.com/f9/bosscats-push-trailer-16616.html#post162318

My trailer will be running 3 12V batteries wired to run a 36V 500Watt motor. At the moment im only running 24V through a 24V controller to power the motor as one of my batteries is bad. When I can afford it Im going to replace all 3 batteries.

Regards
Tom

 

[Nate D]

Hi Nate,

This is the type of solar panel I have...

Ok. I see. Since you are running 24 volts you want to run one panel in series (black to red) to get 24 volts then run the rest in parallel (red to red and black to black) This will keep you at 24 volts and just increase your watts which is your charging power. I have a total of 10 watts and that is working great Once you get the 36 volt controller then wire one more in series to get the 36. As far as solar controller one is not needed. Set up your wiring so it all ends up going into a plug which mates up to the charge plug of your battery pack. This will constantly charge your battery while you moving or parked.

If you need more help on wiring let me know I could possibly undo my neat packaging for sake of helping you with some clear pics which show the route of the wires.

 

[BossCat]

Hi Nate,

This is the type of solar panel I have...

Ok. I see. Since you are running 24 volts you want to run one panel in series (black to red) to get 24 volts then run the rest in parallel (red to red and black to black) This will keep you at 24 volts and just increase your watts which is your charging power. I have a total of 10 watts and that is working great Once you get the 36 volt controller then wire one more in series to get the 36. As far as solar controller one is not needed. Set up your wiring so it all ends up going into a plug which mates up to the charge plug of your battery pack. This will constantly charge your battery while you moving or parked.

If you need more help on wiring let me know I could possibly undo my neat packaging for sake of helping you with some clear pics which show the route of the wires.

Right off the bat im lost, as I always thought you needed a controller or a blocking diode to stop reverse charging? - charge going back into the panel from the battery.

I searched out an old post I made on another forums...

The Gotwind Forum • View topic - What type RESITOR thingy

Wouldn't 2 batteries = 24V blow up a 12 Volt panel? I know my mate blew up his battery charger the other week trying to charge my 36V electric bike battey pack with a 12V charger.

http://www.gotwind.org/diy/circuit.htm

Regards
Tom

Regards
Tom