bluetriforce

Is there any solar powered bicycle out yet on the market? Can solar powered bicycles today or in the future travel the distance between 50 to 200 miles or more on a single charge in one sunny day? This is my first time buying a solar powered electric bicycle.

Thanks,

2manybikes

Not going to happen. Numerous problems. Just plain battery powered bikes have limited speed and range. The cost is very high too. There is tons of stuff on line try a search.
try 12 miles for a range. Charging current, battery technology, cost, not now, no way.

psiphi

In high school our tech class competed in a solar bike race. Our bike had a little motor on the back wheel, and it was more of a power assist type of system. You still had to pedal, but it was useful for going up hills. We actually won the Colorado Solar Bike Rayce sponsored by the National Renewable Engergies Lab near Boulder. The race was 100 kilometers and we took a one hour break for lunch to recharge ourselves and the bike. None of the team members were actually into riding bikes at the time, so the win was pretty good for our little group of nerds If you google "Solar Bike Race" it will give you some web pages with examples of solar bikes. If I had my yearbook with me I would have scanned the picture of our bike for you.

CMcMahon

Is it really a bicycle if it has a motor?

tsiya

If You just get lucky enough to live a few more years, You may just come to the conclusion that a little bit of help ain't nothing to ***** about.
I suspect You have a vision of Yourself at 70, 185 lbs. of
Blue, Twisted Steel, just a couple of gray hairs! Guess What, Tadpole, You just may not ever see Your dream!
Do You even have a clue of just how Damned obtuse You sound?

CdCf

New photo-voltaic cells are under development that are expected to have an efficiency of between 50 and almost 70%.
Let's assume half of the sunlight's energy reaches through the atmosphere.
From a 1350 W/m^2 in space, we'll make that 600 W/m^2 down here in our soup of air.
Let's further assume a net 60% efficiency in all subsequent systems (conductors, converters, electric motors). That leaves us with 360 W/m^2.
If we assume an average sunlight-to-solar cell angle of 45 degrees, we lose 30% of the 360, and we're down to 250 W/m^2.

Now it's just a matter of deciding how much power you want, and how big a system you can afford.
The average touring biker probably puts out 100-200 W, so just 1 m^2 should be good enough.

If you want to do the same with what's available today, multiply the area needed by three, to simulate today's cell efficiency levels of around 20%.

Edit:
I should point out that my calculations are for a bike without any batteries. I.e., you just run off of the solar power without any battery to store it.
Batteries add plenty of mass and bulk, increasing rolling resistance and air resistance.

dee-vee

Id love to have a solar powered 4 wheel bike. I guess it would be more of a car having 4 wheels but you could still pedal when you wanted.

Chuvak

How about a solar powered unicycle? C’mon, cycles are fun just the way they are.

Mtn Mike

Nope

IanB

So a motor bicycle (motorbike) is not a bicycle (bike) then?

GeezerGeek

What do you call a motorized vehicle that you peddle?

Can you call a motorized bicycle a bicycle if the motor doesn't work?

What if the motor works but you don't use it. Then is it a bicycle?

What if you are carrying a motor home in your panier. Then is it a bicycle?

becnal

A moped

Mtn Mike

Pah leeeese. I have never heard anybody with a reasonable expectation of being understood refer to a motorcycle as a bicycle. I'm not trying to play games of semantics here. There are a lot of words in the english language have evolved in the last 100 years to accommodate new technology. Get with the times

The word "bike" however, can go either way of course. I can recall a few individuals in the recent past that mistakenly posted on bikeforums.net bragging about how fast their new "bike" was, including detailed information on engine displacement, and 0-60 speeds, only to be politely informed that this forum is actually dedicated to the pedal variety.

IMHO, BFDN is for those enthusiasts of human powered two wheeled (or one wheeled) transportation, but I am not in charge, so someone correct me if I'm wrong. On these forums there is probably room for discussion on the motor assisted variety of bike, which is what this thread is about. There is a place in the world for motorized two wheeled transport, sure. Maybe they are the answer to our energy crisis? Maybe they will give the disabled the freedom and mobility they deserve similar to these. But I do believe you cross out of the bicycle realm and into the motorized vehicle realm. Above I had succinctly stated my opinion that a motorized bike does not fall into the same category is a pedal operated bicycle .

CMcMahon

Way to avoid the question, (old) guy. I wasn't asking for a lecture on how I'm going to be riding a bike when I'm retired, I was asking exactly how a two-wheeled motor vehicle qualifies as a bicycle.

2manybikes

I don't live in a place where it is sunny every day. For something to be made available it has to be something that will sell well to the public. After all it is about money. If they only make a few the cost would be insanely high.

For something to work in many climates it will need batteries. There are so many electric battery powered bicycles on line to look at it is staggering. None of them have the range you mention or go very fast, and they are expensive. When they run out of juice (you will) they are very heavy to pedal home. Charging them up with the huge benefit of being able to plug them in, as opposed to using solar cells takes a long time. You can't recover much of a charge in a short time. Try Goggling them. They don't sell well because of these problems. I can go much farther and faster on my pedal bike than a medium priced electric bike. Ten times as far. Just a little faster. The present technology and the laws of physics prevent anything else from happening right now.

dbg

You'll spend a lot of money for a very compromised solution. If you want to avoid pedaling, take the bus.

CdCf

But what if you had a bike with a fairing that first of all reduced your air resistance, and if it was covered with solar cells, providing you with (even in places with clouds and low sun) enough power to take away some of the effort?
Let's say you get enough to halve your power input requirement.
You could either go slightly faster, or you could cruise at a very low speed without pedalling at all. Or anything in between...

No need for batteries!

2manybikes

exactly.

2manybikes

Nope !! In the shade and up hill you have to drag the extra weight along it's not efficient at all. It's actually inefficient.By adding all this stuff to a bicycle you are reducing the efficency of the overall vehicle. Making it worse.

It's been done. Find the solar electric vehicle race on line. This is nothing new. I'm not saying it's impossible to make something do this a little bit. But, it has been done over, and over again. Unless you are rich and don't want something practical forget it. There are plenty of vehicles like you describe without the solar cells, you just pedal them. If you build a really efficient vehicle then you might as well pedal. Figure out how many solar cells you need to make 350 watts. That will be ok on the flat, but will not get you up a hill.

Don't forget these fully faired bikes and trikes, of which there are many, are heavy.

The most efficient thing in the world would be to have the cargo load power the vehicle right? Then there is no other power needed..................... ?

That would be a bicycle. The most efficient vehicle known to man.

CdCf

2manybikes, you probably didn't read my post properly.
It's certainly true that a faired bike is more efficient than an unfaired one.
So, when you do have all that fairing, there's no harm in adding solar cells to the surface. The extra weight is negligible.
Then you need a small power converter and a small electric motor.
I would think the extra weight of the whole setup would be less than 4 lbs.
And you can certainly generate enough to help you along well on flats, and take a bit of the strain away when climbing.
The extra rolling resistance from the weight is made up for dozens of times over in the extra power contribution.
You're guaranteed to spend less energy in total using such a system.
If you can't see it, that's not my problem.
It wouldn't cost much, and it wouldn't be hard to build.

It would actually make for a great tourer. Not only could you have some power to reduce your effort a bit on a long leg, you would also have power to charge batteries for radios, mobile phones, digital cameras and flashlights.

2manybikes

Yes it will work fine on a flat surface with no wind and no hills in the sun. I don't dispute that for a second. I have seen it happen.

And yes you can build something too, Is the price even a consideration?

The only thing I am saying is they will not get to market, you were asking about buying something. No one will sell them unless they will work in a wide variety of circumstances. The fully faired bikes and trikes don't sell well either. That's not to say they don't work, they do. But they are very expensive for example.

I don't think the rolling resistance from the added weight is a problem either. It's lifting it up a hill. That needs a lot more power. In a long or steep hill a small weight makes a difference.
When there is not enough sun is not the whole mechanism added weight? I think my 350 watt bicycle motor is a lot more than 4 lbs. but I may be off a little. You need a drive mechanism too not just a motor.
I'm guessing the motor I have is about 10 lb or so. On any kind of a slight hill the strain on the motor is too much, the current drain is too high and it trips a circuit breaker to prevent damage. You need a transmisson to keep the motor in the right gear range for hills. Maybe attached to the pedlals in a way that takes advantage of the existing gears on the bike, just like the pedals do. A chain drive with some kind of a clutch so it can be disconnected when not in use. That would add to the weight of my simple tire drive motor. Did you calculate all the energy losses in all the bearings in the drive system? Did you work out a clutch of some kind?

There's a lot more too. I would love to be wrong and have you build one. That would be great. But the more I know about it and the closer I get, it is impractical to make one for sale as a bussiness so that you could buy one that does what you asked for in your original post. The faired trikes are around $5,000 and up.

Google (solar car race) there is so much to read it takes too long, there are details about the last EIGHT YEARS of competition and all the teams and etc. People have been working on this for longer than eight years. lots of specialists in their fields all working together. Some smart people have been working on this for a long time.

CdCf

Who's talking about selling?
I never saw this as anything but a homebuild.

Yes, if your read my first post, you'll see that I added losses, probably a lot more than there would be in a good system.

To be honest, I only calculated how much power you could get from solar cells to drive a bike forward.
And 350 W is far more than a regular biker will be able to put out for more than a minute or so.
I was thinking of adding 100 W or so, to take the strain off. And that wouldn't go away if you're going uphill.

There's no reason why a faired bike would cost as much as you say, but that's another issue entirely.

2manybikes

Oops. sorry. I meant the original question in the thread was about buying something. Big difference between building and buying yes. The finished faired trikes that are for sale are more than that. but I was getting confused, thinking about the business of selling a finished product to the public and having a successful business. The original question in the thread also was implying "on a single charge" so I was thinking along the lines at first of a battery powered bike with a solar charger. We were not really on the same page.

My main problem with a solar assist no battery bike is that when the sun is not out does it have enough light to produce enough power to carry it's own weight? I don't know the answer to that question. If it does not, Then after the first few cloudy days a user is not going to be a happy camper. I can see in a sunny climate where it is flat, and there are plenty of those, it would be good as a home made add on. I live in New England, so if there was a store selling them here they would lose lots of money. Maybe not true in Florida near the golf course, retirement communities. I think they sell a fair amount of battery powered bikes in a place like that. Or in LA.

I agree on the wattage but the bike rider with 100 watts or 200 watts has to use a transmission effectively to climb any incline at all. I was trying to illustrate that even though the motor is 350 watts which will push a heavy, heavy old trike at 16 mph on a flat surface, without a variable gear ratio it is useless even on a slight hill without gearing changes. Or if it is geared low then It is useless to go 16 mph on a flat surface. That is a problem that has to be solved and it adds weight cost and complexity.
I don't have an answer to that. I don't mean it can't be done, but how would do it that keeps the weight down, and the cost low? I'm trying to envision a competed project that solves all the problems.
If you have a good answer I wish I had it last year when I was researching the drive train for my electric trike. No one has solved this so far that I know of. My feeble legs using the gears on my bikes will go up hills that that motor with one gear could not even move on.

mikethebike

Hey! You nay sayers forgot about the Wright Bros? Never fly !
Weren't the Brothers bike mechanics ? OK heres something I saw in Wired Magazine called the Ambient Light Vee; a three wheeled solar powered vehicle. https://www.bookofjoe.com/2005/01/httpwwwwiredcom.html
The plans to build this are free. Max Speed 21mph, range 170 miles. The inventors/mechaincs, Jeff Dekzty an Will Scully said" We had to stop for an hour to recharge, so we had a sandwich"

a positive imagination,
MTB

2manybikes

This stuff has been around for many years,there's tons of these. They all are at the same level of develoment. Ten years that I know about and before that.