How far can I go on my solar powered bike?
HTML-код
- Опубликовано: 28 июл 2023
- On your bike. To try everything Brilliant has to offer-free-for a full 30 days, visit www.brilliant.org/simonclark. The first 200 of you will get 20% off Brilliant's annual premium subscription.
I try to cycle to 200km to London using my Ridgeback electric bike, towing a solar panel behind me to charge the battery. Along the way things don't exactly go as planned, and I learn some lessons about low carbon transport.
Previous video on my e-bike: • Are e-bikes worth it?
Video on decarbonising transport: • How to decarbonise tra...
Equipment used:
- Mobisun panel 100W / 18V
- Mobisun Pro | Portable solar generator, 70,000 mAh
- Ridgeback Arcus 1
You can support the channel by becoming a patron at / simonoxfphys
--------- II ---------
More about me www.simonoxfphys.com/
My second channel - / simonclarkerrata
Twitter - / simonoxfphys
Insta - / simonoxfphys
Twitch - / drsimonclark
--------- II ---------
Music by Epidemic Sound: epidemicsound.com
Some stock footage courtesy of Getty.
Edited by Luke Negus.
How far can you go on an electric bike? I attach a solar panel to my e-bike and find out! I try to cycle from Bath to London and learn lessons about the scientific method, how to run an experiment, assumptions, and come to a realisation about low carbon transport.
Huge thanks to my supporters on Patreon: Felix Winkler, CC, Rebecca Rivers, Thomas Charbonnel, Mark Moore, Philipp Legner, Zoey O'Neill, Veronica Castello-Vooght, Heijde, Paul H and Linda L, Marcus Bosshard, Liat Khitman, Dan Sherman, Matthew Powell, Adrian Sand, Stormchaser007 , Dan Nelson, The Cairene on Caffeine, Cody VanZandt, Igor Francetic, bitreign33 , Thusto , Andy Hartley, Lachlan Woods, Andrea De Mezzo.
Chris Conrey, Lord Gigenshtain, Christian Weckner, Frida Sørensen, Ned Funnell, Corné Vriends, Aleksa Stankovic, Meagan, Indira Pranabudi, Chaotic Brain Person, Simon H., Julian Mendiola, Woufff, Ben Cooper, Mark Injerd, dryfrog, Justin Warren, Angela Flierman, Alipasha Sadri, Calum Storey, Mattophobia, Riz, The Confusled, Conor Safbom, Simon Stelling, Gabriele Siino, Ieuan Williams, Tom Malcolm, Leonard Neamtu, Brady Johnston, Rapssack, Kevin O'Connor, Timo Kerremans, Thomas Rintoul, Lars Hubacher, Ashley Wilkins, Samuel Baumgartner, ST0RMW1NG 1, Morten Engsvang, Farsight101, Haris Karimjee, K.L, fourthdwarf, Sam Ryan, Felix Freiberger, Chris Field, ChemMentat, Kolbrandr, , Shane O'Brien, Alex, Fujia Li, Jesper Koed, Jonathan Craske, Albrecht Striffler, Jack Troup, Chrismarie , Sven Ebel, Sean Richards, Kedar , Alastair Fortune, Mat Allen, Mach_D, Keegan Amrine, Dan Hanvey, Simon Donkers, Kodzo , James Bridges, Liam , Wendover Productions, Kendra Johnson. 
Наука
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 seems the most plausible explanation to me
The possibility of rattling breaking the panels proves how bad an idea this is. Just take two charged batteries and have your mom keep two charged batteries for the way back. No reason why we can't have a standard bicycle battery and swap them out at the post office like some people do with gas canisters (obviously not at the post office).
@@ElectricityTaster just wrong kind of panel for the job, it's possible to have wiring which handles that.
@@myownsiteCorrect. RVs commonly have modules which are hardened for vehicular application. I (person who has been doing PV for over a decade) also wonder what the impact of shade is on the charge rate. If he was zipping through trees on the trail, the charge controller could have had a very hard time getting much juice back into the battery. Once he hit a main road, he got a lot more SoC per hour, suggesting the shade had something to do with it.
Just as likely rattling those "flexible" panels destroyed them. They're still made of rigid crystals, thin ones, and it's more useful to think of them as "slightly flexible, once" panels - glue them to a curved surface and you're fine, use them as a wobble board and they'll generate just as much electricity as a wobble board.
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.
add tree/house shade on top. You will probably only generate 10 to 30% in the shade. AND maybe a too low current cutoff.
Some devices will cut off charge if it is too low voltage/current. They cut off the charge in order to not damage the battery
it's the rocket equation but for e-bikes
Also the air resistance of the trailer.
@@noergelstein While true, that would be more about the consumption rate. It would not affect the charge rate.
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.
It still wouldn't have been enough.
@@tams805I could could do It. Just need a ticket from Arizona.
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.
The 120km was a day trip. 20kmh avg; 25 max.
And get some replacement parts like a chain if you try it again. Had some major failures in the middle of nowhere... and walking 10km is not nice. It's even worse if you bleed or you injured yourself. Been there, done that. Got no T-Shirt.
You can long-distance drive a electric kickscooter aswell. External Battery; and go nuts. But prepare for the worst falls you've ever had when you encounter gravel without suspension. Had a hacked together M365 that drove for 50km on one charge.
This panel can put out close to 100 watts ruclips.net/user/postUgkxOqI2yqX0XVrhR2BMJciTWrHJpG8FhJyg 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.
that is awesome, do you frequent any fora on this subject I should be aware of? I am in the process of planning a trip to the black sea from the Netherlands on my electric bakfiets ;)
Hi Alex, which type of Charger do you use?
Michael
@@michaelpoier5699 hi. Boost charger that take the lower voltage from the solar panel and boost it up to the correct charging voltage for the battery. I only use Genasun. There are no real alternatives unfortunately unless you go cheap and buy the Chinese options that does not perform nearly as well. Genasun are over priced in my opinion but the best.
Could you please make a video about your bikes and their design. It would be nice learn about them.
@@k1zmt there already is a good video explaining pretty much exactly what I have been doing.
Me personally. I use the motor only when I really need to. Uphills and when get going. Using this approach and mindset “flattens” out the ride and you save your own energy for the easy pedalling. Using this method I can travel further than normal and solar can keep the battery happy.
ruclips.net/video/14yliWlykfg/видео.htmlsi=fNHVGASytcJqODJo
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.
A recumbent bike might make the lack of wide paths even worse. The trailer he was pulling was giving him issues and a recumbent bike is going to be at least as wide.
the solar race cars in Australia used to have a second category for pedal assist bikes. But experiments here have shown that the way to make it work properly is indeed a trailer with solar panels, you just need a bigger trailer (and use wider roads). There's also a lot of skill in designing a system that copes well with partial shading, especially rapidly changing partial shading.
I had a recumbent that was about as wide as a regular bike, more agile than this setup with trailer. Still not great on rough terrain as you're less able to shift weight with your body. But taking rough terrain really asks more energy to begin with. There are experiments around with solar velomobiles, the 'capsule' recumbent bikes.
Or just buy a “velomobiel”. That’s a very streamlined bike which can easily do 45 kmh. WITHOUT A MOTOR!
Such things do exist, they do not solve a fraction of the problems.
This cannot work until we have vastly more efficient solar or reduce the power draw to an insignificant degree, making it moot.
Tldr just bike.
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
I don't think he'd get much futher than he did on the first battery - the motor output is mostly fixed and it's up to the rider to put in any extra effort required. I think a better test is to try with the motor turned down to 100W (which is probably enough to get to London) and then a standard road bike (which is also enough to get to London) and see which is easier. Does the 100W cover the extra effort needed to pull the trailer?
Have you ever ridden a bike with a lightly loaded/empty trailer? The difference in the effort needed is negligible.
@@filipvidinovski7960 yes, but he says in the video how he kept having issues with the trailer on the narrow paths that he wouldn’t have had with just the bike. I meant the drag of it on the bad terrain and grass and the break going on, not just the weight and tires
I'd guess he would probably be better off without the trailer. I could easily get 100km on my ebike (same european limits on power etc.) with low support on one battery, with that rough narrow path that trailer probably used up a lot of power. And remember, if you go 25 km/h, your power usage quickly drops to zero.
This video raised so many questions for me for how it could be pulled off, like if he just took 3 charged batteries and left the whole trailer etc behind he could probably make it especially if he found a plug to charge a bit while he ate lunch.
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
Yes
This is the answer, unfortunately the person who made the video doesn't understand how solar panels work or read the comments which tell him what the problem was.
@@StartledPancake yup, that's the biggest problem here. And flexible panels rattling that much will be destroyed quickly.
Maybe the heat reduced the panel efficiency? It tends to have this kind of effect on batteries
Yes, panel heat reduces efficiency. According to Wikipedia: "An increase in solar cell temperature of approximately 1 °C causes an efficiency decrease of about 0.45%."
Yes, a bit , but by far the biggest problem is that solar panels only capture a small percentage of solar energy. A relatively low powered bike will use many hundreds of Watts. A solar panel that size will make one hundred in ideal conditions. That's why solar powered vehicles are ultra streamlined and covered in cells.
@@alexanderdaum8053but even a single cell on the panels shaded, will easily half the output. Heat really isn't as much an issue, else there wouldn't be panels flat mounted on roofs.
@@Beeeeeeeeeee Yes, when the cells are connected in series (most are), shading a part of the panel will make a huge difference. That also applies to multiple panels connected in series.
However, temperature can still have a significant impact (although far less than 50%).
Tech Ingredients ran a test on this (ruclips.net/video/Mt9qLRN7JvA/видео.html).
With some cooling at ~40°C the panel produced 63,4W.
Without cooling at 53°C it produced 58,7W.
That's a 7,4% efficiency loss from just 13°C temperature difference.
The problem is just, that panels aren't that expensive, and installing them with cooling would be much more expensive than just adding a few more panels.
They do make panels with cooling and it's actually extremely practical to do so, because the heat you extract from the panels can be used to do something else. It's called a PVT panel combined photovoltaic and thermal. You run either plain water or an antifreeze-based coolant through tubes mounted to the back of the photovoltaic panel and then you use that heat to do something like heating a swimming pool. You do have to use some of the generated electricity to run the circulator pump for the coolant, but in general it covers its own costs.
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!
Spot on.
The rated power is at standard conditions (1,000 W/m2 of irradiation, cell temperature of 25ºC and 1.5 air mass).
The power test needs a pyranometer to check how much irradiation is reaching the panels.
And, as you said, seeing how much shadowing the panels had during the journey, the panels not being pointed to the sun and the dust on them, the power output of the panels was severely affected.
Nonetheless, great video. I hope he can come with a different rig and route so he improve efficiency and test it again.
I was thinking the same thing. In the brief shots of the trailer, it appears he had part of the structure overlapping the panels, so I think the bottom row of cells was partially shaded 100% of the time. If you were doing this permanently, you would want a frame above the entire trailer that the panels went on top of.
The rope over the solar panels is killing the efficiency...
Solar cell area doesn't lie. There's no way that panel was capable of generating 100W unless it was nearer to Venus!
Putting a "100 W" sticker on a 50W panel does not turn it into a 100 W panel, as much as Chinese sellers would like you to believe.
The biggest issue here was shading - notice the wheel casting a shadow on several cells, as well as the yellow towel underneath.
The panel needs to be in a tiltable frame and raised above the wheels, and also bigger. Then it might generate enough to be useful with a decent MPPT charge controller.
My small experience with these kind of solar panels is that any kind of shadow falling on them, even on just one cell, will greatly drop the output. So the rope across the panels, and any blockage at the bottom by what he's used to protect it from shock, is killing the output.
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.
I already done this myself Simon. I'd recommend more efficient bike tires and use a rear rack and try to fit everything on it. It's not ideal but would solve the added friction problem you had
The problem he had wasn't added friction, but insufficient power from the panels, trailer or no trailer. If the panels were mounted on the bike itself, his range wouldn't get significantly better.
@@filipvidinovski7960 Fair point, he didn't get the power he thought he would get but he also put more effort and had less range juste because he was using a trailer, I believe he said that himself in the video. He would've gone farther with 2 full batteries without any trailer.
@@filipvidinovski7960As i understood it he got 45km on the first charge and it took 4h. That is a pretty bad performance for an ebike. Definitely there was a lot of drag.
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: www.thesuntrip.com/en/
I followed youtuber Jack Butler on his Sun Trip ride to China 4 years ago - amazing. I think the width restriction for a bike trailer is 80cm, so I guess you would need to make your own panels. I made my own using A3 size foamboard for lightness, with sunpower cells and it was very time consuming and delicate work!
I made 4 x 100 W 36-cell panels, (144 cells, 6 x A3 x 4) and they weigh about 1.1kg each. I carry them in panniers or a backpack because they aren't very waterproof though it would be good to find a way of mounting them. However, they are easy to set up for a quick charge. I think Simon needs to learn about the amazing machines that people have built for Sun Trip!
I've always wanted someone to do a suntrip setup where they charge during the day and then pack up into a aerodynamic recubant and only ride at night. it will probably never happened for safety reasons but I think It could be a very fast strategy.
@@purplepenguin43 No time for sleep? If you're not moving when charging, then you have to go much faster to catch up.
@@purplepenguin43 and/or take naps from 10 to 2 during day.
@@ahaveland Thanks for the mention ;)
You may have much better results using a higher quality sunpower or renogy panel with genasun or victron mppt controller tuned to your battery's max input current and connected for direct DC charging. Some of the cheaper controllers will delay supplying any power to the battery for as much as a couple minutes after going through shade and returning to sun so this may have been a factor. If you were using a inverter with the bike's AC charger that would have also taken a big toll on efficiency which should have been taken into account in your calculations.
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.👍
This video has over 500 comments. Just about two of them mention the object covering the panel. I sadly think he won't get the info. He will never know the main reason he failed: Covering just 5% of the panel can produce a loss of over 90% of production or even worse.
I am currently working on my electric cargo tricycle, going to make it into a little teardrop camper covered in solar so I can travel Europe with my doggy, so this video was timed right for me and I enjoyed it a lot but most of all I got some really handy pointers to take into consideration, Greetings from the Netherlands!
In a moment where you stopped for lunch and were surprised the panel wasn’t producing much, a wheel was casting a shadow on the panel. A one-wheeled trailer might have been a better choice.
If your planning on using solar as your charge source, your plan of route should be the one that has the most sunlight, it looks like the bike path you took, is 80% shade, so a route on the roadway looks like it would have been a better choice. 😁👍
Creditable effort! I have ridden the grand union and the towpath was surprisingly uncomfortable. I live in a rural(ish) area and have made good use of an e-bike to pick up materials and tow the kids point to point, its a second car for us (maybe the only car if we can get rid of our remaining diesel).
The Australian solar car challenge is proof-of-concept. Lots and lots of panels. Very small aerodynamic cross section. Very sunny locale.
6 Mile round trip with a tow to pick up my groceries ... I couldn't do without my electric bike. My car won't pass inspection ... Car needs $4,000 worth of repairs ... Electric bike with saddlebags and backpack have been lifesaver. 🙌☯️🙏
1. Build your system on a recumbent bike with a windshield and a flat roof.
2. Put solar panels on the roof, plus the trailer.
3. Put reflecting mirrors around your solar panels.
This will reduce your wind drag, be more comfortable to pedal, and more than double your solar input.
Yes, and giving the rider shade will decrease fatigue. Possibly have the roof able to be tilted to angle in to the sun too
A battery bashing experiment , i use two 48v 28.8 ah triangle upp batteries that fit in panniers perfectly, for long distances . If i take trailer i put another spare one in that . I adapted the trailer you got and put on 26" wheels and used a fish crate , super tough and way less bouncy,,also handy spare wheels in an emergency .
If you wanted to repeat this experiment you could get a hold of or rent an electric cargo bike like a bakfiets, rather than riding with the draggy trailer, you could mount the solar panel over the cargo box like a lid with some method of angling it one way or the other to point south. Get a hold of a rigid panel the generates about 200 watts instead of your little floppy one. Using the cargo bike is a good move because the load will be in front of you and watch what it's going to snag on as you go.
What I am missing is the charging conversion loss. From the video I can't tell, but if your Mobisun charge controller is also an inverter to 230V which feeds to a cheaper battery charger, you easily lose 25% there, plus, say, 20% to the battery itself (you never get out the same amount of Watts that you put into the battery)
Got so much more than I expected. Great video, cheers :D
Especially liked that you wove information on how to test hypotheses into the whole thing
18:45 On weighing up a road bike vs a pedal assist bike.
I have done this calculation before. My commute to work is 25 km; slightly downhill the whole way to work, slightly uphill the way back home.
It takes me pretty much exactly one hour to get to work by bike, and about 30min-45 min to drive on a good day, and 1-1.5 hour to drive when traffic is terrible.
So i have seriously considered a pedal assist bike (partly because of your first video on ebikes), especially since the main barrier that keeps me from cycling to the office more often is just plain tiredness (I can't do two days in a row I have found, I must alternate).
But the top speed of ebikes (25km/h), the cost, the weight, and the battery life (of the entry level brands), made me realise that I really need a pretty decent ebike, rather than just a cheaper bike (that I would be able to get in the malaysian market here), to make it competitive against my roadbike. Especially since it would be a lot of deadweight that I have to drag with me if the battery dies.
So here's hoping ebikes get better (spec-wise), and cheaper.
I don‘t now about your local laws but here only the slow e-bikes do 25km/h and the other ones (up to 45km/h) are just legally essentially small motorbikes and you need the license and registration for it.
Also if you are still considering it, I would probably rent one for a week first.
just get a farty moped
@@PhilfreezeCH Well, we are still in the early days of e-micromobility here. The govt did implement a blanket ban on e-mobility vehicles on the road as a reaction to electric share scooters on the road in a viral video. But, it's sort of not really enforced. Electric motorcycles do exist too, but I also want the benefit of exercise that pedal assist bikes also have.
Bicycles dont have any such restrictions, as they are sort of grandfathered in in the traffic code. I happen to use the motorcycle lanes that follow one of the highways in my city; it was one built decades ago in the era of the bicycle and was designed with them in mind.
The motorcycle lane is actually what allows my commute to actually be feasible; malaysian cities are generally not particularly bike (or even pedestrian) friendly. The city is crisscrossed with highways.
The selection of ebikes available here aren't as great as what I am seeing online in the UK and Europe, so I think I will hold off from that option for now. But yeah, thanks for the suggestion. Definitely try first before I buy, since I wouldn't want something that might not be suited to my conditions. (I have also contemplated building my own on top of my existing bike, but put that off as technically challenging, and quite a bit of road.)
@@elaiej There are some decently cheap Chinese ebikes that go fast, good range and still have pedals for assist.
@@znail4675 👍
I considered a Xiaomi Himo because I saw it for sale on an e-commerce site. But there were only 1-2 sellers, and very few reviews. So I held off.
For now I plan to wait for a bit. Wait for the prices to go down, and for there to be more choices.
I think having the panel attached to your backpack would give you some amount of charge without being in the way. Additionally just having the panel with you let’s you charge throughout the day so technically speaking so long as you have food and water the bike should take you anywhere the land allows you too.
Glad to see my hometown Pewsey's station getting back on the big screen after it's crowning moment at the start of The Lion, the Witch and the Wardrobe
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 cycled bath to devizes on NCN 4 in May. Really overgrown and narrow . Over the last couple of big cycle tours I've seen lots of people using ebikes. They usually charge at wherever they are staying. Sometimes a cafe will let you plug in, but I 've only done that with something smaller than a ebike battery. My problem is that the batteries on phones and cycle computers no longer charge from my dynamo. So I have a 30W solar panel designed to be draped over a backpack and I'm going to put it over my rear rack and paniers.
Love this video! Fantastic example of the difference between theory and practice. As an engineer, I see this all the time and sometimes, experience is the only way to learn your conclusions.
Dunno how the algorithm will take it but I like this kind of irl content + storytelling + educational value as a complement to the usual voice over stuff. It’s fun and I hope it does well enough to merit more similar videos.
A failed experiment is still a failed experiment (or can an experiment ever truly fail?)!
I have never used an electric bike (my city is so flat and small enough that I just walk everywhere) but this just showed me again that they would be great for a hilly city and those short 15-20 min (by bike) commutes that tend to get a bit tedious on foot if you have to do them every day.
I've had the same idea before, though never got to the experience because my calculations were basically pointing to the fact that for the extra weight (and cost) of a solar panel, you are better off grabing 2-3 extra batteries to go further. I once did 90 km on a single battery (though I was dead tired at the end of that), so with a few batteries that journey to London would be a breeze!
you can apply a voltage to the solar panel, film it with an IR camera.
Solar panels are just fancy IR LEDs, so those that are working as intended will light up in the camera.
Was going to suggest that. NREL have a video "Invisible damage from walking on a solar panel". Camera needs to be near infrared. Any smart phone or gopro etc with the infrared filter removed works work. Would the by-pass diodes cause problems? Not sure off the top of my head...
great video. When I looked at this. Thinking about cycling my e-cargobike from dorking to Brighton and back, the numbers I got lead me to the conclusion that the best/simplest/cheapest/easiest answer would just be to buy more batteries for the bike, charge them from my homes solar system and then take enough batteries to cycle all the way there. Charge while in Brighton and then cycle home. Which didn't seem very interesting, so in the ended I worked out a way to carry a child on a Brompton and we just got the train.
That was super neat to see! I kinda figured it wouldn't wok out but didn't expect it to fall so short, or to be because of the extra weight, drag, and difficult terrain. I really wish we had the rail systems and infrastructure in the US to make a similar experiment possible.
You were on the right track as the system was not regenerative and the solar panels were weaker than obtainable these days. This was a good experiment that needs work to succeed. My hats off to you mate.
That's great ! Thought of doing the same with my ebike , but for the same issues decided on restricting range to two batteries here in rural ontario. With a road choice of highway or gravel back roads, a trailer is only for short rides. E bikes a fantastic piece of kit for those short 10-15K trips though out here. Wish i had one when biking in downtown Toronto dodging dump trucks and taxis. cheers
Micro cracks in the photo cells (see video "Invisible damage from walking on a solar panel" from NREL which take advantage of the fact that solar cells act as near infrared LEDs when they have a voltage applied to them). Also I noticed some shading from some fabric @3:41 which can be significant depending on panel internal configuration.
Nice video! After taking part in the Sun Trip I'd highly recommend a single wheel trailer, less drag and feels so much nicer. I like that you came to the conclusion that solar off the bike makes the most sense, as outside of a crazy adventure designed to promote solar power, it does make the most sense!!
Great video, and it’s amazing to see a failed experiment given so much attention. I would also add the power loss between the act of charging and discharging. The solar power might generate 100w but only 80w will be actually stored and then of the 80w only 60w will be used to power the wheel (for example) I believe it’s called charging loss
Damn those are some huge power losses, i would realistically expect the charge controller to be in the high 90's efficiency so maybe a max of 10% power lost, not 40%
Ahh you were in BOA! :) I've cycled from there to Bath and the terrain really isn't great! I arrived in Bath exhausted not because of the distance, but because of being constantly shaken by the towpath. I think this video helps show the importance of decent infrastructure for active travel though! Towpaths really shouldn't be used as an excuse for councils to not build proper cycling infrastructure due to their terrain, width and lack of decent lighting
There are some great one-wheeled trailers for cargo transport. Just wanted to tell you that.
Thank you though! This is good info when considering cargo bikes for child transport and child carrier trailers. I knew 2 wheels side-by-side was harder for snow, but you have exposed several other factors. Thanks ❤
Considering it's 100 miles to the nearest train station, I've definitely thought about how to make this work. Too bad it's not really meant to be. There is a unique sort of peace that washes over us when on long bike rides though.
Love the transport tycoon clips!
Micro-mobility is a very interesting challenge, and the even smaller folding e-bikes, or kick-scooters are in my opinion an even better example of a mode of transport that can take you from your home, to the closest train stop, and from then onto your final destination.
Would not try any journey longer than 15-20 mins when I can take public transport instead (if I lived somewhere that had anything decent).
Electric Unicycles are great for micro-mobility in that they are both easy to store at home, but also to take on trains or into stores.
Yes, you could spend thousands of dollars on an eBike ruclips.net/user/postUgkxUiL0GnyDjP32RJdd660sP8mZk4CRLTCJ and get something much higher quality. However, if you're looking for a basic model to try out eBiking this is a great choice. The assembly is easy as far as bikes go (took about an hour for me to do, I'm not an expert). All tools needed are included. I added the plastic mud guards you see and a more comfortable seat. The other reviews are correct that you're probably going to want a better seat (Giddy Up! Bike Seat is what I got - super comfortable). The battery easily handles a 2-4 hour ride if you add some of your own pedal power. I haven't even gotten it up to top speed yet - it is very fast. Components are not top of the line, but decent for the price and work just fine. It works great on dirt roads and singletrack and pavement although too heavy to do tricks or any serious technical mountain biking. I'm looking forward to using it a lot over the summer. Tons of fun!
This was an excellent exposition of the scientific method!
Love this video. I had thought of the same project some time ago. To make this work, you may have to go with a smaller more efficient ebike motor and many more solar panels.
I LOVED this! So helpful to walk through your experiment process. Really great!
Have you tried pointing a lamp on the panel? Jokes aside, this was a very cool thought experiment, also loved the approach to the issue. I think you'd have to factor in also muscular activity as source of energy (how much energy to make your little snacks? Hehe). All in all, i didn't expect a 100w panel to carry you to london but i surely hoped it could
Make the lamp solar powered, and get the solar panel's energy from another lamp that's powered by the first lamp. It's infinite energy!
Devizes, famous for being the place where the device was first invented. Now, devices are all over the world. An amazing success story. Similar is also true for Bath, of course.
Getting to Pewsey felt like something out of a Top Gear viseo. Great moment!
There’s one category of loss that you omitted, loss associated with charging and discharging. And if you really want to succeed in getting all the way to London, there’s a lot you can do to optimise your system. The easiest would be to ditch the electric assist altogether. But other than that, a more efficient bike (road/gravel style), a more streamlined trailer, preferably single wheel for towpaths - or just use the roads.
We actually did something like this for our senior project... it also failed lol. I think given advances in battery technology, and probably lighter batteries, we could soon have e-bikes that could go medium to long distances without needing to be charged much on the road.
It's already here. I got a bike that should manage that distance with a battery swap.
I would have guessed that only half of the panel was working properly and the other half had broken during the trip.
So I assumed this too and so tested this off camera - both sides are still generating!
Huh, I thought that was a slam dunk theory. How wired it's so low then
@@SimonClark the tiny shadows from the wheel and yellow umbrella would have had an enormous effect on the power production. The cells are connected mostly in series, so if one solar cell goes down, the rest can't produce
@@SimonClark Check the fine print. Maybe you bought a 100W solar panel but 50W are locked behind a subscription service.
The output of these solar panels really does vary - I have a similar portable 200 watt panel (good luck getting that on a bike trailer!) and the output varies by the minute between 20 watts and 160 watt+ depending on cloud etc., and meticulously moving it to point towards the sun. I can't imagine there was much output from that panel in and out of shade, different angles etc. - enough to charge a phone maybe!
Thank you so much for your content. Your videos and especially your book are awesome.
Simon, flexible solar panels are notorious for failures. They are cheap for a reason. Also, depending on the way they are wired, even a small shadow over a small section can cut electricity generation to a large section or all of the panel.
The experiment had some... major design flaws.
almost like I made a whole video about that fact
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!"
What if you have an injury and can't cycle up a hill?
Just create a standard bicycle battery format and rent them at petrol stations or post offices. Battery running low? Swap it for a charged one along the way. Pay for it via an awkwardly-named subscription service such as "swapify".
@@ElectricityTaster My point was that the concept of a bicyle that isn't purely powered by muscle power is no issue to me. But seeing a solar powered bicycle mentioned elicited the picture of Simon just sitting on a bicycle, not pedaling, and the bicycle still moving in my mind. And since pedaling is such a vital part of riding a bicycle, be it a regular one or an electric one, my brain broke a little.
Also, yes. "Swapify".
@@ElectricityTaster If you can't cycle up a hill you can't walk. Gear ratio and range before battery with added weight. Cycling is much easier on the legs than walking.
Great experiment. I have always wanted to try that, now I know some thing to watch out for.
This is a scenic route. I wish to take one day. Good to have such experiments for fun and outdoors enjoyment.
You gave it a try. Good for you.
I have a trailer also, I have 3X17ah battery's and a small 700 watt petrol generator, I know it's sort of defeating the object but it works great, doesn't matter if it's over cast, I can charge while I ride and the generator is actually lighter that a 100 watt solar panel.
14:47 actually makes me hopeful at that point, it's more than what you had in the other battery when you swapped! so if you manage that again, you are actually getting a budget surplus! Can't wait to see what happens next!
edit: you didn't try swapping again to see how much you had!
That surplus was more to do with the fact that he had a big lunch, during which it could charge. That was much more time than when he went to the train station afterwards which was also covered by shade more. He wouldn't have had a surplus there
@@Stroopwafe1we’re talking about 12% in 3 hours versus 18% in maximum 1 hour. This _had_ to be a rattling issue.
Really enjoyed this format of video!
Those folding panels are quite well known for breaking when abused. I suspect all the bumps broke many of the cells, which is why you're only getting 45W from a 100W panel.
BTW, were you able to charge your bike from the mains sockets on the train? IIRC, the UK was 30-40% solar powered during those sunny days, so that would sort-of count ;-)
That panel was far too small to generate 100W. Maybe it could do it in the vicinity of Venus! Area doesn't lie.
Some things could have been optimized as you know:
1. the route: paved roads or cycleways cost so much less energy, especially with a trailer. The horsepath on the canal is much more beautiful for sure but too narrow and uneaven for the trailer.
2. the trailer: single wheel versions have less friction alone because of less wheels, but in reality they are even more effective because they follow the bikes wheels and do not go through the flowerbeds too much and the whole ride would be smoother and more comfortable.
3. the human part of propulsion: train a little and you can minimize the electric assist, which if brought to almost zero, the endless travel is possible!
You'd probably have been better off with pannier bags without the panel and a few extra spare batteries instead for a trip this long. No idea what that number of spare batteries would be as you pointed out it highly depends on the route you take and what kind of assistance mode you're in. Depending on what kind of place you're traveling to I'd personally prefer to charge at the destination or maybe sort out a spare battery.
However I fully agree with the sentiment at the end, even if you can make it possible it still won't be the most reasonable method of transportation. Around an hour travel time to the destination is where the threshold for me is after which I don't consider the bicycle an everyday practical trip option. For leisurely sightseeing route though my body will reliably tolerate 4-5 hours total on the bicycle with some breaks. On a good day I could go much longer but I've got no control over when the chronic illness wants to torture me, at least I know on the day itself when I wake up if it's bad or good. The only thing I can really do is managing the lower back pain with enough of the right exercise and if needed paracetamol on top of the regular NSAID.
I do like the concept though but I would want the solar panel in a more integrated setup at rack of the bicycle instead. Ideally so that it can easily be stowed between the rear wheel and the pannier bags that any functional bicycle for me will have. And to make it perfect it should be able to fold out from there without having to fiddle with plugging stuff in, just a small nice panel sitting at the back over the two pannier bags. Would produce less power than a large one on the cart, certainly if the rider is blocking the sun but it'd be hassle free and charge things a bit while riding and not be too wide for a normal path with other traffic. The main charging benefits from it I'd expect to be while it's parked stationary, to make that more effective adding the ability to control the angle would be nice rotation in one direction would be enough provided there's enough space to turn the bicycle however you want. Additionally it might keep the sun a bit off the pannier bags which in my case often contain groceries, including cold/frozen stuff in one of those insulated bags with a few of those hard plastic exterior ice pack things for coolers inside.
With such hilly terrain the capability to charge while using the bicycle could have an additional benefit if it has a front or rear motor combined with a controller supports regenerative braking for the descent.
Thank you for this video it is a brave thing to set off on this long journey with an electric bike where others would use a road bike. One thing you have forgotten is you have two wheels with a dynamo attached to each, you generate 10W of power at 6V.
If I was approaching this subject and after watching your video, I would be starting with three fully charged batteries.
Your test was interesting and at the same time I found the canal route fascinating and beautiful for bike or e-bike travel !
Loved the video ! 👍
Having done several long-distance rides on my road bike (plus a 46k ride this morning), my biggest concern with you doing a 200k was not the battery but making sure you yourself don’t get too exhausted, dehydrated, or sunburned.
Honestly I think I overpacked on food and water!
There are two places in the USA called Middle and Nowhere. For an experimenter I'd have figured you'd have used a cargo net over the back of the trailer to keep stuff from falling out, to bring along a multi-meter to test things with, and would have known that folding flexible panels aren't ideal for many uses. Plus a light meter could have been used to record when you were in different lighting conditions, for how long, etc. Cuts out the guess work for solid results.
I've always wondered how much it would help to put a solar panel on an electric cargo bike like a Bullitt since they wouldn't suffer from extra drag from a trailer, just a little more weight.
I had been musing over this, and figured that if you're rich enough the simplest solution is just to have multiple fully charged batteries at the outset. Plus an e-bike designed for longer distances, like the Cannondale synapse.
As for the whole "just take a train"...yeah, my nearest station is 35 miles away. Joys of rural living!
Sending good vibes Simone!
Instead of a trailer, which adds a lot of weight and friction, you should try mounting the panel flat to an extended pannier on the back of the bike, basically no extra weight or friction and you can still use pannier bags either side of it.
Also if you can make it clip onto the panniers it could be detachable so you can take your bike on the train more easily
There's an annual solar e-bike race for I think over a decade now called The Sun Trip where competitors try to cross an entire continent over a week or two on nothing but an e-bike with solar panels, no wire charging permitted, and if memory serves me right single riders are permitted two square meters of panels and still have to do most of the work themselves except on the most blue sky days. Goes to show just how much solar power you need to make an e-bike self-sustainable.
I did this year's suntrip through the alps, you can get away with less than you think but you're not wrong, as many solar panels as possible. A number of people run a relatively normal setup whilst riding but bring out the foldable stuff to boost when stopped. The min solar surfdace area allowed was about 0.8m2, the max whilst riding was about 2.5m2 but the max overall was around 4m2 this year if I recall correctly. Come and get involved, I should be there for 2025! Cheers
As a dutchy, I cycle to work on an ebike. Across flat terrain, on good roads on days with out wind, and on the lowest setting (which is my normal setting), my battery says it can do 120km.
With some headwind half the time, I find that I need to recharge about once per 8 or 9 days, which is 11km * 8 = 88 kilometers. The battery is never empty by then, maybe 20-30%.
Long story short: I thought you could really make it to London, until I saw the road condition & your battery drain over time. I bet you could make it in the Netherlands
You simply need more batteries. Charge when necessary at a local pub, restaurant, cafe and hotels. I did a long range trip on my ebike 660 km in 5 days using a 72 volt 50 Ah battery. You would get longer range with a recumbent with larger and more efficient solar panels on the recumbent and a bigger and more robust trailer with suspension to protect your electronics.
This was a really good video. More adventury stuff like this in the future could be fun.
These flexible PET solar panels are less efficient than those for installations for several reasons.
1. thermal management: heat = less power. The PET panels heat up and the efficiency decreases. The 'big' brothers have at least one side made of glass with an aluminium frame.
2. cell technology: there are many different cell technologies: HJT, TopCon, Perc etc.
3. Sub beam angle: As you have seen, the angle is crucial ;)
4. PWM or MPPT charge controller? It should be MPPT.
I would set up two panels with aluminium frames of the same type as a house roof and connect them in parallel. This will give you the best energy yield. Don't forget to attach a diode to the positive poles of each panel to prevent reverse current.
Otherwise...cool thing! Keep it up ;)
Written by a random dude from Germany.
Cheers 😊
On twitch, there is a streamer called "Hitch" he is cycling from Belgium to the North Kapp with a 200W solar panel made by "Yverr", (also a twitch streamer) for powering his stream, not the bike.
So far he hasn't used a wall socket to charge his batteries. The solar panel was made for an ebike race, also without using external power but only sunlight.
Cool experiment with beautiful scenery!
Excellent and entertaining to watch! Great video!
I know your hypothesis was to make it fun and interesting, but here's my experience and perspective :)
As an E-Gravel cyclist, I can see many improvements here. The choice of tires and their pressure, bike and trailer weight, motor efficiency, improved aerodynamics (frame design, rider position, clothing, aero bars, etc). Probably charge with larger panels when resting? it's more stable, cleaner and nothing's rattling when charging.
I have two 250 Wh batteries and I can ride over 250km with them on mostly flat terrain. It would be a bonus to charge them with solar panels, but my body wouldn't accept more than 250 km in a single day. For climbs, each battery brings me up over 1000 meters, about 50-60km for a total system weight of 110kg.
But back to your experiment, I never thought a 100 watt panel could ever deliver 100 watts to the battery in its most ideal scenario. Each of these components reduce a certain percentage: Solar panel (around 18-23%; ratings differ from factory to only 1 minute after each charge, they simply drop in % in real world), the converter module is usually around 85%, the battery charger (also similar to the MPPT module efficiency), and even the battery is never 100% in its optimal capacity, especially yours that are 2 years old.
I would rather look for pit stops at cafes, restaurants and even free wall plugs in each city. Some even use car charge stations to charge their ebike.
Since you have 2 batteries, carrying a spare charger (on a rear rack) to charge simultaneously would be a better choice than hauling a trailer (10-15 kg) and a solar panel (2-4kg).
At the risk of posting an overly long comment, as someone who has worked with solar PV for around 30 years your problems with "unexpected" low output from a PV module is very common. There are several factors at play here which contributed to your woes (fair play for doing this btw, excellent video!).
1. Module orientation: Your module is relatively flat, the rating of 100W on the module will be for "standard" sunlight (taken as 1000w/m2) which is what you would expect in the UK in the summer on a clear day...but this will be delivered by the sunlight hitting the module at normal incidence. Below 10 degrees inclination the output falls somewhat, and of course if the module is not pointing at the sun in the sky the angle of incidence is also skewed off 90 degrees by that. Whilst the summer in the UK is not too bad as the sun is high in the sky you will probably loose significant because of this.
1a. Kind of related to the above, the module on the trailer is not flat/planar but has curved. This is a problem because the cells are in series so the current will be limited by the cell with the least light energy falling on it, depends on the cell arrangement in the module but in general a solar module should be flat, facing the sun, and between 15-50 degrees inclined in the UK in the summer. All of this is super hard to do on a bike trailer.
2. Temperature. The module will be rated at 100W at STC (Standard test conditions) usually 25 degrees C and 1000w/m2 as PV cells get hotter their output reduces (typical for semiconductor devices) so a module with cells at 40C which is not unusual for a module in the UK in summer will reduce output by 10-15% typically.
3. Maximum power point/voltage matching. This is usually the big one. I don't know what the electrical arrangement for the battery is but a solar module will only produce that advertised 100W under STC (as above) AND when the load is matched to the optimal voltage of the module (Known as the MPPT voltage) this is to do with the maximum power theorem. PV modules produce variable current depending on light intensity, but the voltage is relatively constant. A typical 36 cell PV module will have its maximum power at around 16-17V (around 0.5V per cell) so if you connect a 12V battery which is charging at 13V then say the module has enough light to deliver 2 Amps of current this would be 2x13 or 26W if the module was running at 17V (too high for a 12V battery) then the power would be 2x17 or 34W. If the load voltage and module voltage are mismatched then they can be fixed with a "MPPT tracking regulator" which is a DC-DC voltage converter but whilst these are common devices on bigger systems they are less common on small portable devices. Also there is an unfortunate tendency for sellers on a lot of e-commerce platforms to sell "MPPT" regulators that are in fact the older PWM type which don't do the voltage matching which can mean huge losses due to voltage difference between the load (battery) and module.
4. Shading, the partial shade from the trees is great for keeping you cooler but as mentioned above the module will only produce the current that is supplied by the most shaded cell so that can greatly reduce the overall energy yield.
The combined effects of these factors often means that people see outputs of only 40-50% of what they think they might get from an X Watts solar module, some are hard to avoid when mobile but some can be mitigated by good design. I used to work powering outdoor events and festivals with solar and learned very early on its a great technology but needs careful design to get the best results.
This is the most I have ever typed on a RUclips video and I hope it helps. If you want to do more solar cycling and would like some design advice drop me a message and I would be happy to help. I only just found your channel and is great, thanks :)
I love seeing these kinds of things. I'm thinking more efficient panels, more of them (maybe a canopy), and a dedicated MPPT DC to DC charger fine tuned for this would really be required to make this useful.
doesn’t work on such a small platform, it would only increase dead weight.
@@TAmateurGuyYou're probably right, but I think with lightweight panels, a canopy, and a dedicated MPPT, you could get a kilowatt hour of power per day that it sits in the sun. The real question is, if you did build a sort of extremely lightweight aerodynamic canopy and use flexible panels and aluminum how much would it reduce the efficiency of the bike? because on a normal ebike, that would be about 3 miles of extra range a day. But if it adds too much drag, you're right that it would come out negative. Still, I feel we're at a place where this is becoming a possibility, and with careful engineering, I believe it could be useful today. I'd like to be able to charge my bike by leaving it out in the sun for a few days.
@@TAmateurGuyOh, I double checked my math, I was way off, that's the range for cars. On an e-bike, 1kwh would get you something like 60 miles . So, even with reduced efficiency, It seems it would be very useful.
@@jameshughes3014 Thanks for taking the time and checking it. I really haven’t worked on any similar projects, mostly did research on large scale PV system controls but this is really interesting and I would have tried to build something from ground up if I could find the time.
Did you account the extra weight?
I’m not sure about torque produced in this platform. Did you you account the non consistent radiation lvl and angle as well? I would propose building it on a platform with variable angle for extra efficiency but it really comes down to amount of weight we can tolerate.
But generally bikes don’t offer the surface area required to produce enough electricity, and even cars have trouble producing enough power.
Again thanks for replying and have a great day.
@@TAmateurGuy that's the question, but even if range was cut in half, and you could only realistically pull 750 watt hours a day, that's an extra 12 miles of range easy. However I just watched a video where a guy did just that, and he was able to ride at 6mph with no battery at all. The weight didn't seem bad. They do make light weight panels, you just have to give up some efficiency. So I think it is doable
Q: What’s the only thing that whines more than an E-bike motor?
Ans: The rider 😊
Simon that trip would be ultimately doable on a bike you just need to ditch the “E” part.
Sure, it wouldn’t in anyway be practicable or easy, but you could do it. It would only ever be a “challenge”, but people do these types of challenges all the time. You only have to look at the many and varied bike backing youtube channels etc.
Just sell or park up the E-bike, buy and ride a normal bike for all commuting and training.
Train, get fit, learn how refuel your body on big days and then do the ride next summer.
Get healthy whilst trying not to add to the destruction of the planet, achieve a significant personal challenge and show the world what's possible. Win win win.
You do get MPPT boost charge controllers intended to charge a bike while riding.
One bike in a RUclips video had a beam connected above the back wheel, with one solar pannel on each side connected in parallel...
Very interesting idea as I own a very similar solar panel myself. Thank you for sharing this with the community too. Although i would say that its hard to find a solar panel that will give you 100% output even on sunny days.
I bought a rear mount child bike seat, when by 1st child was born (took a couple years to grow into it). It was fun taking my 1st child out for bike rides.
When baby #2 surprised us, I bought a front mount bike seat (now having a rear and front mount). It was fun taking them both for bike rides.
When baby #3 surprised us, I sold the front mount (as the youngest one out grew it) and bought a bike trailer + kept the rear mount).
So...I can take all 3 for a ride. 2 in the trailer and 1 in the rear mount. Now, I just gotta convince my wife to get her bike out of the shed.
I have a tandem I converted to electric and a 170w solar panel, I might have to get a MPPT charge controller and put them together to see what I can do! Currently swapping out the BBS02 motor for a Tongsheng TSDZ2B (for the torque sensing PAS). Things for you to think about for next trial, tandem/longtail bike (instead of trailer), torque sensing PAS and a battery blender so you can charge the battery in use.
Out of curiosity, Simon- how heavy are those batteries, and how expensive? In order to make the journey, it seems like you'd need about 6 fully charged batteries to complete. So, how feasible is that in terms of expense, weight and "faff-factor"? Standardised, pre-charged, easily replaceable batteries for EV's have been often discussed in the context of long distance car journeys, to reduce the time element (delay) associated with repeated charging stops (despite what the manufacturers claim the ranges are).
Various cities in India are trying to standardize on a single e-bike battery form factor so that they can replace all of the two-stroke motorbikes that make the city full of smoke with e-bikes, all you have to do is visit any number of street stalls or stores and swap in your empty battery for a fully charged one.
@@AlRoderick Sounds like a brilliant idea and great if they can make it work.
Some have speculated that perhaps only half of your array was working due to a broken connection due to the vibrations from the rough path, others have speculated that the array only ever was capable of 50W in spite of the "advertised" output. I tend to agree with the latter. Also, dragging that trailer behind you really increases the amount of work required, and hence power draw. I would say it easily doubled the amount of power required.
I did the math on this a while back, and concluded that unless one carries 10m^2 worth of solar panels on a trailer at all times, it's not worth it. I assumed the setup would be used on cloudy days, was facing flat upwards (w/o trying to optimize the angle while riding), did not use fancy GaAs cells, and did not require $1mln in funding and a team of 10 rich Stanford undergrads to build an aerodynamic velomobile out of carbon fiber. I assumed 250W output, AFAIR.
It was a hot day and panels are less efficient with tempeature. But as they were moving I expect air to cool them off a little...
Never heard of the Sun Trip? Some blokes rode 10,000km from France to China with Solar bikes. Then all around Europe. Next year is to Morocco and back. Been going over a decade already.
Just like, get bigger & more panels lol. There are no rules against it. The UCI has no power here. lol. You can mount panels to the front and rear and eliminate the trailer. One winner did that one year. i think recent designs are trending towards velomobiles and recumbents and using the panels as shade.
The biggest limit is whether you want to stick to the legal classification of an 'ebike' and not step into 'electric motorbike' or 'electric car' territory. It's POSSIBLE to just have like... a dozen square meters of panel with you and then you'd really get some speed.