Would A Solar Powered Bicycle Be Possible?

[Jay Lakoda]

How many square feet of solar panels would be necessary to power a bicycle? I'm imagining a bike with little solar trailers.

[Acme]

It's kinda one of those 'it depends' questions. Start with an electric bike and a 12volt deep cell battery. The battery is rated in amp hours and you only get about 80% of the rated value. So if you have a 100 amp/hour battery and your motor is using [guessing] 5 amps, then the battery will be drained in 16 hours. Photovoltaic panels are rated in amps [amps = watts/volts] so if you have a 1 amp panel [about 15 watts] it would take about 80 hours of good sun to charge your battery back to full. You can calculate differeing battery ratings, number of panels, and amp ratings of motors to suit your specifics using my examples. Have fun!

[Jay Lakoda]

Thanks! Maybe I'll just have to stick to peddling my bike and powering my electronics with solar panels. Well, that's the plan anyway.

[Acme]

Thanks! Maybe I'll just have to stick to peddling my bike and powering my electronics with solar panels. Well, that's the plan anyway.

G'donya for the effort. Every little bit helps.

[Enthalpy]

A competition in Australia does it with (very purposely built) cars. These cars are rather large, very optimized (wheels as good as a bicycle, streamlining far better), and they run through sunny Australia at good speed.

 

Extrapolating from this, I doubt a bicycle without a hull, with a smaller area, and in a more cloudy climate, would perform well.

 

What you can do is have a battery-helped bicycle, a big solar panel at home, and charge the battery there from Sunlight instead of mains electricity. Have two batteries if you drive during the day.

[EdEarl]

A 60W solar panel is about 2.5ft². In a strong wind, it might make a bicycle dangerous to ride.

[Acme]

A 60W solar panel is about 2.5ft². In a strong wind, it might make a bicycle dangerous to ride.

Got a reference for that? If true, I'm behind the times because my 1ft X 3ft panel is only 15 watts.

 

Maybe the panel could double as a sail!

[EdEarl]

Got a reference for that? If true, I'm behind the times because my 1ft X 3ft panel is only 15 watts.

 

Maybe the panel could double as a sail!

Sorry, that should have been (2.5ft)².

[Phi for All]

I have this awesome little lantern I give away to good clients. It has a small PV cell on top to charge the battery, and also has a hand crank. It has an AM/FM radio too, but the best part is the USB ports so you can charge cell or laptop. I almost forget it's also an LED lantern.

 

I wonder if something like this could be set up on a bicycle (maybe using the guts from the lantern). Attach the hand crank generator to your wheel, charge your phone while you ride, charges as the bike sits in the sun, listen to music, and even power a headlight at night. It's not an electric bicycle, but this is doable for about US$25 and some ingenuity.

[Acme]

Sorry, that should have been (2.5ft)².

That's not quite right either. Your total area would be 6.25ft². Advert says 44 5/8" x 19 1/4": 44.625 X 19.25 = 859.03125in² divided by 144in² per ft² = 5.96ft². Call it 6ft², so 10watts per ft². That's overestimating a bit too because the frame is part of the total area and produces no juices.

 

Nevertheless, it is twice the output per ft² of my current panel so I am indeed behind the times. [My 15watt panel is over 10 years old.] And $500!? I think mine was $120 back in the day. Egat Brain.

 

PS Keep in mind that a high output panel shouldn't be connected directly to the battery as it will 'overcharge'; you will need a charge controller in the circuit.

Edited July 7, 2014 by Acme

[sunshaker]

I think it is down to getting area of a solar panel down, I do not know if this is a workable idea,

But as black absorbs photons, I thought about some kind black sphere that absorbs photons, coated inside with some material that reflects photons/light(materials now that can reflect almost all light, two way mirror light goes in but can only exit through aperture)) which could then be focused through a small aperture onto a solar panel, So a small solar panel could be used.

 

perhaps create a black bubble vehicle. Or just have a sphere on a pole

I can imagine a solar panel under this sphere or inside which would power a vehicle similar to this.

Edited July 7, 2014 by sunshaker

[Acme]

I think it is down to getting area of a solar panel down, I do not know if this is a workable idea,

...

Yes, it's the area but specific to the output of that area. No, it's not a workable idea but kewl looking droid there.

 

Anyway, the OP seems to be asking if solar PV panels could power a bike directly and the answer is [theoretically] yes. In all practicality however, the answer is no.

 

I did some checking and found a bike motor kit. [$1,500!! :0 ] bike motor kit The motor is rated 36V, 350 watts/700 watts peak. I suspect that peak is getting it started so you need panels giving at least that. You would need 36V panels because most panels have diodes to protect from bass ackward connections and you can only connect them in parallel and not series. So we'll take Ed's panels and presume 36V & 60 watt. 700/60=11.66 panels. Call it twelve panels @ 20 lbs each and you have 240 lbs & 72ft² of surface.

If you ride into some shade or turn so the panels don't face the Sun, so long power. So not really practical.

[sunshaker]

I was thinking if a solar panel was in this kind of sphere it would collect light from 360degrees, Plus there would be no light energy lost to reflection, As it would bounce around inside sphere and the internal solar panel would use 100% of light/energy absorbed by sphere, Plus it would have better aerodynamics.

Edited July 7, 2014 by sunshaker

[Acme]

I was thinking if a solar panel was in this kind of sphere it would collect light from 360degrees, Plus there would be no light energy lost to reflection, As it would bounce around inside sphere and the internal solar panel would use 100% of light/energy absorbed by sphere, Plus it would have better aerodynamics.

Well, it doesn't work like that. If it did then that's how engineers would build PV systems.

[lamironi]

Solar bike is very interesting idea. Sunlight utilization to drive and for other purposes ...

[John Cuthber]

As far as I'm aware, all bicycles are solar powered.

[timo]

A more straightforward scenario, though admittedly not exactly being what the OP asked about, would be solar-powered charging stations for bicycles with batteries. Those could be full e-bikes or, currently more likely, the very popular pedelecs. This could be integrated at home (trivial solution), at the workplace (technically pretty much the same, but possibly with extra constraints from stupid laws), or at bike-rental stations (most innovative but also most interesting). Conceptually, electric bikes would not be too different from electric cars in this picture.

[Ophiolite]

I have this awesome little lantern I give away to good clients. It has a small PV cell on top to charge the battery, and also has a hand crank. It has an AM/FM radio too, but the best part is the USB ports so you can charge cell or laptop. I almost forget it's also an LED lantern.

 

I wonder if something like this could be set up on a bicycle (maybe using the guts from the lantern). Attach the hand crank generator to your wheel, charge your phone while you ride, charges as the bike sits in the sun, listen to music, and even power a headlight at night. It's not an electric bicycle, but this is doable for about US$25 and some ingenuity.

I am devastated. All this time I thought you were a scientist and now it turns out you are an engineer,

[Phi for All]

I am devastated. All this time I thought you were a scientist and now it turns out you are an engineer,

 

I meant in theory, of course.

[Acme]

A more straightforward scenario, though admittedly not exactly being what the OP asked about, would be solar-powered charging stations for bicycles with batteries. Those could be full e-bikes or, currently more likely, the very popular pedelecs. This could be integrated at home (trivial solution), at the workplace (technically pretty much the same, but possibly with extra constraints from stupid laws), or at bike-rental stations (most innovative but also most interesting). Conceptually, electric bikes would not be too different from electric cars in this picture.

Good thinkin' Lincoln. I would just say that stupid laws never saw our homes as an impediment.

 

I ride a tricycle and gave some thought to putting an electric motor on it, but I don't ride it enough to make it worth the trouble and expense. It might be nice on some steep hills, but otherwise it would be robbing me of the exercise benefit.

 

Appension: Then there is the novel idea of doing a web search for 'solar powered bike'.

 

Solar Powered Bike

Saturday, October 3, 2009

116 Miles Today

A personal record. I estimate about 10 miles of this was on solar power, 50-60 miles on charge stored in the batteries (including a 3 hour recharge at a solar-powered facility using plug-in AC battery chargers) and the rest was good old fashioned pedaling. My cruising speed was usually between 20 and 30 miles per hour, depending on the terrain and headwind/tailwind. Here are some numbers for those of you who like numbers:

 

Total Distance: 186.9 km (116.1 mi)

Moving Time: 5:46

Average Moving Speed: 32.3 km/h (20.1 mi/h)

Max Speed: 66.6 km/h (41.4 mi/h)

Min Elevation: -76 m (-249 ft)

Max Elevation: 197 m (646 ft)

Elevation Gain: 1433 m (4702 ft)

Max Grade: 23 %

Min Grade: -14 %

Edited July 8, 2014 by Acme

[random]

I know just enough about solar power to be dangerous but there has been huge leaps in efficiency namely http://www.psfk.com/2014/02/solar-panel-magnifying-glass.html#!bhM96t seems to me you could build off of this technology to increase efficiency therefore lowering the size of the solar capture panel needed.and/or substantially reduce the battery charge time......or melt the solar panel into a big blob of goo with your awesome solar laser !!.