How far can I go on my solar powered bike?

I have a feeling that your distance estimates are further affected by the weight of the trailer itself, considering that when the electric motors assisting you, it now has to do extra work.

If it generated 100W the new output is conveniently half, and it seems to have two distinct modules. Maybe one of them got disconnected in the rattling. I’d do the output test again and seeing what kind of an effect covering half of it has.

This panel can put out close to 100 watts youtube.com/post/UgkxOqI2yqX0XVrhR2BMJciTWrHJpG8Fh… when positioned in the appropriate southernly direction, tilted to the optimal angle for your latitude/date, and connected to a higher capacity device than a 500. The built in kickstand angle is a fixed at 50 degrees. Up to 20% more power can be output by selecting the actual date and latitude optimal angle.The 500 will only input 3.5A maximum at 18 volts for 63 watts. Some of the excess power from the panel can be fed into a USB battery bank, charged directly from the panel while also charging a 500. This will allow you to harvest as much as 63 + 15 = 78 watts.If this panel is used to charge a larger device, such as the power station, then its full output potential can be realized.

I have been doing solar powered e-biking for 4 years now. Last trip I did was 251km in one day. 50% battery left out of a 1100wh pack. Charging and using the same battery. I have a high quality 160w panel on a single wheel trailer. Boost charge controller. I had fun watching your experiment but I guess you need to do it again.

What I've learned from long-distance e-bikeing is that you need to stick to roads. Gravel eats power like crazy as you don't have a smooth rolling surface. If you stick to those you can get 60-80km from a 1.1kWh battery with an avg speed of 25-30. 120km when you take over when it reaches 25, and/or lower the support. My current record is 2h for about 60km on one charge. Early morning, no cars on the road/people on the path.

I think the best way to do this would have been with two fully charged batteries to start with. Set off until 90% charge for the first one and then switch and get the solar panels working. Longer distances to cover, and the solar panels get to work for longer.

I think the way to get this to work is by using an electric (if that exists) streamlined recumbent bicycle and covering it in solar panels. That way you start with a more efficient bike to begin with and you can add solar panels on the body which, if you do it right, wouldn't impact the friction that much. You would melt into a puddle in it, though.

Now you need to do the same route without the trailer and see if you could get as far on one battery without the drag from the trailer

Next time use a custom built e-bike that does not use a battery at all, and just uses DC straight from the solar panel. That would be actually interesting to see how far you could go.

Great video! Solar powered ebikes have been done very successfully. The Sun Trip is a solar powered ebike race. Next year's race is 7000 km long. They tend to use bigger panels than you've got. I read of one case using a recumbent trike with a solar roof, and a trailer with more panels. They could do something like 30+ km/h at mid day while increasing their total battery charge, so they had juice left for after sunset. With enough panels and batteries, you could keep going 24/7 until collapsing from lack of sleep. Even in overcast and rain you get some power from the panels. I've been interested in trying this myself. But to account for all the factors you describe so well, I'd be looking at something like 400 watts of solar panels for a 250 watt EU pedelec, which would require a very big trailer, like 1 m wide and 2 m long, the size of a bed. It would be both heavy and vulnerable to wind, and should probably have suspension. I'd have to build it myself, and bike paths would usually be out of the question, due to barriers and concern for other path users. I have done long tours on unmotorised bikes. The solar assist would make the hills easier, but the trailer would hamper the ride a lot, like you experienced. Parking also becomes an issue, and you'd be more vulnerable to technical problems. I'm not sure it's worth it for me. Maybe when I get older. The Sun Trip: https://www.thesuntrip.com/en/

Maybe the heat reduced the panel efficiency? It tends to have this kind of effect on batteries

I have some suspicions of what cut the efficiency. 100W rating is rated at peak, or solar noon, and with the panels orthogonal to the sun. Any variation to that will have a pretty major impact. Any shadowing too, will kill efficiency since a number of the individual cells will be connected in series, and having even one be shadowed and drop in voltage, effectively creates an open circuit in that series. Add everything else (extra rolling resistance, charging circuit losses, trail vs. road riding), I think it did pretty well! It would be interesting to see a velomobile with solar cells give this a try… Any way, great video Dr. Clark!

There are 4 things that i think happened. 1. Miscalculation on the extra weight of the trailer slowing ya down. 2. Wheres the regenerative braking? Put a more efficient motor/generator on that thing. 3. You lost a trace on your panels. Only half is connnected. This is endemic to flexible panels with conpanies using as little metal as possible to connect all the cells. Fix; use a hard panel. For the application, I'd also use a larger panel. In the northern latitudes clipping is almost a necessity, ya just got to come to terms with it. 4. If youre using a PCM charge controller and not an MPPT than your panels charge nothing when any part of them hit shade. It just shuts the whole thing down. MPPT still takes the power from what cells are still generating. The difference between the two is like PCM: MPPT Flintstones vehicle: Tesla. Just throw pcms away. Theyre garbage unless you live in the, essentially, in the Atacama. I applaud the bravado. Diving in head first with half the facts is literally how civilization was built. Book smarts will never account for field knowledge. At some point you just have to get out and do it and see what you failed to preconceive. This is a feature of life, not a flaw. It'd be so boring if everything was figured out before doing.

12:16, since this is suspiciously close to 50% of the power, i would try to block each half of the panel to see if it makes a difference, maybe one connection got broke and half the cells are disconnected. edit: just saw you answered to that theory already, weird that it's not the case.

I've never had any issue with the pure concept of e-bikes. But when the notification for this video popped up on my screen, I read the title and just thought "If your bicycle is solar-powered, you're doing bicycling wrong, you use your legs!"

Maybe i missed it, but did you take charging/discharging efficiency into account? Putting 100Wh of power generation via the solar panels into a battery wont result in the battery delivering 100 Wh to your bike. So you probably have another 0.5 factor you would have to account for. I know a few people that have those ultra low drag bikes you lie down in. Equipping one of those with a battery, electric motor and a solar panel could actually make a big difference and there it could actually be viable.

nice try, but i saw some potential problems in your design. 1. Around the 3:40 time point you can see that the yellow object overlaps with the solar panel. which cause a great loss of efficiency.2. you then also have a loss of 2 times with the charging and discharging of the batteries and for profit you should immediately inject the energy of the solar panel into the inverter of your bicycle.3. with the cart you have 4 points of contact which gives more friction losses. but still great effort.👍

It’s fun to experiment. My self build electric ebike has 125-140 mile range running on its 14 cell 42ah (2.5kwh) battery pack built using cells from a Nissan Leaf electric car, charging in 45 minutes with a 30amp charger (I have an adapter to use public electric vehicle charge points. Solar is great but you need two 345w panels (so 3 X 2m surface area) to get any benefits from it. I converted my sail boat to electric drive and this solar set up as a canopy works well when sailing for the day replacing the 15% we use from the 5kwh 48v battery in good weather.

I saw that you had something covering parts of the panel at times - even a tiny bit of shade can ruin the output of an entire panel depending on how it’s wired

I would have guessed that only half of the panel was working properly and the other half had broken during the trip.