It's RadWagon 4 with white paint job, upgraded brakes/power controller, and solar panel at the top of the stock roof.
Not quite what I expected when I read the title.
Btw, the panel is 50W, and I assume the battery is stock, 672 Wh. That's 14+ hours of best-case sunlight to recharge fully. I wonder how practical is it.
It isnt practical. The trickle from the solar panels is basically irrelevant. It would be far more efficient to attach the panels to a grid, somewhere they can operate coninuously with a view of the sun, then charge the bike off the grid. But virtue signaling is often more important than practicality.
I think it's a matter of scale. That's a 50W panel, it would relatively expensive to get an inverter and an inspection/plan from your power company just to be able to use the grid as a battery. Also it would be less efficient because of the AC conversion.
My personal preferred way to do this would be to have a stationary battery to charge up, and better solar panel positioning like you say, but that costs a bit more for that stationary battery. And if the only thing that battery/solar setup is used for is charging the bike, and you don't actually need more power then all that extra power is just gonna go to waste.
Yeah, such cost is my blocker to install cheap solar panel on my home. On-grid solar system equipment is expensive but I don't have any good use case for unstable off-grid solar. If I drive e-bike, charging removable batteries by off-grid solar looks perfect use case, but I always drive a car.
The solar inverter for my off-grid setup does allow for fallback to grid power if the solar and battery are out. So I would be able to do stable "partially solar" power without having to dump power back into the grid. Still not sure it's worth the cost, as you'd need a very consistent power draw to make a return, or batteries that make the return take even longer.
Still a fun project though, and not something I built to make a return on.
I'm waiting for someone to build a grid-solar hybrid refrigerator/freezer that can attach to a 50w or 100w PV running at "low-voltage" ie: < 48V. No permit/electrician required, no grid-intertie inspection required.
Modern fridges are often inverter drive, so should be easier to incorporate a DC power source. And they generally run all the time because they do variable-frequency drive.
Best part, it keeps working during power outages. Extra points for putting on a USB charging port (only works during the day, but still!).
I am waiting for the same, but with air conditioners. A crappy $100-$200 window unit, plugged into an equally baseline solar panel. Free opex cooling that could be installed for basically no work.
An air conditioner - even a crappy $200 window unit - will draw an order of magnitude more power than OP’s 50 watt refrigerator. You’ll need much more solar, either more panels or bigger panels (likely both).
Ah nuts, you are right. Cursory glance is showing smallest AC units at 450 watts. Still kinda-sorta-attainable by a couple of bigger panels, but significantly more capital expenditure when hoping to get some minor "free" cooling.
It's sounds like this IS (mostly) a case of charging the bike "off the grid". If the trickle charging changes the usability of the bike from "charge it every 2-3 days" to "only charge it when there's multiple cloudy days in a row", that's a huge step up in convenience.
The RadWagon 4 has a listed range of 45 miles. In practice, people seem to be getting closer to 30 miles. The modifications look like they'll add some drag, so let's say it gets 20-25 miles per charge.
If you leave the bike out in the sun all day, you can probably add 10-15 miles of range, which would be practical for some people (not everyone of course, but for many people, an e-bike wouldn't be practical even with infinite range).
I don't know where you're talking about, but only Arizona and SoCal get close to the 7-8 Peak Sun Equivalent Hours you'd need to get.
But yeah 7-10mi realistically in most of the US or 5mi in the winter. That's not terrible, but it does require pretty perfect alignment and no shaddowing.
For a daily short commute it is probably enough, it would be for my daily commute of 40kms total on a pedelec. This is also a pedelec, so the practical answer is that it doesn't matter in any dimension since it can be charged from a wall when it's not sunny and it can be pedaled if it runs out, but it would be fun to know how much they have to plug it in.
In a pedelec after a certain point you and the battery are working together to maintain speed and it really doesn't take much battery. But there are so many variables that it's hard to talk about it meaningfully.
Yeah, makes more sense to leave the solar panel in your backyard (saving some weight) and have spare battery always sitting on the solar charger.
Then you can bring your bike inside, in the shade, etc. — not having to always find sunlight to park in.
The only way bringing the solar panel with the bike makes sense is a multi-day ride. But as is being pointed out, you're going to be spending a lot more time sunbathing rather than biking under power.
> The scalable, “#motionless” #WindEnergy unit can produce 50% more energy than rooftop solar at the same cost, said the company.
> The technology leverages aerodynamics similar to #airfoils in a race car to capture and amplify each building’s airflow. The unit requires about 10% of the space required by solar panels and generates round-the-clock energy. Aeromine said unlike conventional wind turbines that are noisy, visually intrusive, and dangerous to migratory birds, the patented system is motionless and virtually silent.
> An #Aeromine system typically consists of 20 to 40 units installed on the edge of a building facing the predominant wind direction. The company said the unit can minimize energy storage capacity needed to meet a building’s energy needs, producing energy in all weather conditions. With a small footprint on the roof, the unit can be combined with rooftop solar, providing a new tool in the toolkit for decarbonization and energy independence.
> When they tested the device, the MIT researchers found it could generate 730 watts of power per kilogram when freestanding and about 370 watts-per-kilogram if deployed on the high-strength Dyneema fabric, which is about 18 times more power-per-kilogram than conventional solar cells.
> “A typical rooftop solar installation in Massachusetts is about 8,000 watts. To generate that same amount of power, our fabric photovoltaics would only add about 20 kilograms (44 pounds) to the roof of a house,” he says.
> They also tested the durability of their devices and found that, even after rolling and unrolling a fabric solar panel more than 500 times, the cells still retained more than 90 percent of their initial power generation capabilities.
E.g. Hyperlite Mountain Gear sells Dyneema ultralight backpacking packs and coats. There are Dyneema Patch Kits that work for various types of gear.
Wise to look at Ultralight backpacking gear before buying regular camping gear. Solarcore Aerogel is warm and light and also in encased in PVA foam rubber which is like a new wet suit. https://twitter.com/westurner/status/1600820322567041024 Kayaking bags are waterproof, but are there yet Dyneema ones?
> The only way bringing the solar panel with the bike makes sense is a multi-day ride. But as is being pointed out, you're going to be spending a lot more time sunbathing rather than biking under power.
I guess the sensible way would be just having bigger, fold down solar panel array and to deploy it where you stop.
I did run the math for our last extended bike tour and even that doesn’t really work out. We carried two pairs of 650Wh batteries for our cargo bikes and made around 60-90km per day. This used on average half a battery charge, so ~600Wh. Foldable panels of reasonable size and weight top out at 300W. So best case, ideal conditions, no charging loss you’d need 2 hours to top off each bike. Add non-ideal conditions and charging losses and you’re easily looking at 6-8 hours, a significant chunk of your day. And you’ll likely need to carry an inverter, since DC chargers for e-bike batteries don’t seem to be a thing. We ended up carrying an extension cord.
Things may work out if you plan on having a stationary camp somewhere remote.
Most people plan to ride during the day and stop at night. While you can get some charge over lunch break, the best charging hours are probably when you are riding.
I use a bike with a 400Wh battery for errands and social visits daily and charge it once a week running on eco or normal mode. My cargo trike which gets used a lot less has a 200W panel and I don't even have to think about parking it outside rather than in the shed, just the charge from parking durkng whatever errand is run means it comes back with higher charge than when it left if it is down from the parasitic drain.
The way that controller and charger are mounted to the chassis without any real shock absorbing measures is asking for trouble, I've done something similar and I think that half the work was to make sure that shocks from the road on the frame did not make it to the electronics or the battery (and that system has worked well for about a year now).
Also, the electronics are mounted out in the open and on top of a small bit of wood, that works well in the lab but if you're going to be biking and end up being rained on it may well cause issues, just using splash proof connectors isn't enough, you need to protect the electronics from the elements by eliminating direct contact with the elements. Much like in a car: all of the connectors under the hood are waterproof and they are under the hood, not out in the weather.
For most shocks a little foam goes a long way, having the electronics be bolted to a cushioned box or having the electronics laying in foam (with appropriate cooling) helps a lot.
Source: I cushion my robots this way, haven't gotten to the ebike yet.
Bikes operate in a pretty tough environment, especially potholes and vibration need some careful thinking when it comes to the effect on your design. Potting is best but then you have to be very careful about managing the heat. Your robot experience will serve you well when building an e-bike but beware of the weather, heat, rain, snow, ice and UV are all pretty rough on electronics, enclosures and wiring.
The whole is mounted in a trespa box in such a way that there is a few millimeters of shock mount in all three directions (very high density foam) and all empty spaces are completely filled up. That box in turn is then mounted to the frame again in a similar way, I tested the whole using dummy weight and the accelerometer in a phone to see what happened when jumping a pothole at speed (which is about the worst that you could do to this bike) and it came in well under the limits and also tested it on a very rough path to see what it would do when subjected to vibration. The front fork is a very nice 'Fox' unit with adjustable springs which have been set to be in the middle of their travel range when the bike is fully loaded and so that it never bottoms out even under the worst conditions.
On the whole it isn't perfect but good enough for many years, I've run this setup for a year now and have once (at 5K km) inspected the wiring and the battery welds and everything seems to be holding up quite well. Things to be careful with: overpressuring the tires would reduce the amount of shock absorbing capacity quite a bit (and is definitely not recommended with tires this wide anyway), the rolling resistance of these is fairly high but that is just how they are designed. Then, obviously there is bumping in to things and falling at speed, which fortunately hasn't happened. But if it did I would immediately consider the battery pack a write-off in spite of being super well protected. I've done about 10K on it now and when it hits 20 I'll take the whole thing apart to see if there is any wear that is hidden from view. I'm mostly concerned with the battery welds and the wiring, those are the weak points, even with all of the wiring contained within the enclosure, routed carefully to never cross over any other wires and with the welds checked using a FLIR during a pretty rapid discharge (twice as fast as the motor could ever do).
The OP has mounted the charge controller and the motor controller to a piece of wood (which will flex a bit but not much) which in turn appears to be protected in only one axis (side-to-side) and is either free to move or rigid in the other two. The wiring runs 'cold' without any kind of extra protection through the wood that it is mounted on. The frame is unsprung as far as I can tell, which especially for the front is not a luxury on a bike this heavy, which makes bike+battery the unsprung weight (I think I see a saddle pin with a rubber mount so there is some flex there). That battery box may have some foam in it or some other suspension for the battery which is good.
As long as he's on good asphalt this setup will work, but as soon as you go on less perfect roads I think that it will give trouble over time. DIY stuff like this looks great on the day you build it if you don't build it for abuse, but exposed wiring is dangerous and vibration as well as the weather are going to be rough on this. I'm curious what it will look like a year from now if used intensively, and also how the wire runs are on the other side of that board.
Tricky to pot something that will make a lot of heat such as a charge controller or a motor controller. You will need to carefully manage your heat if you do that.
There are ways to pot circuit boards with heatsinks. The best way is to attach the heatsink, then cover the heatsink with something like polystyrene, pour over the epoxy, and then dissolve the polystyrene away with a few drips of gasoline.
End result, everything is perfectly potted except the topside of an aluminium heatsink.
A larger panel could easily charge that battery and have the added benefit of shading the rider from sun and rain. Lightweight (4lbs/2kg), flexible 100W-300W panels exist that are pretty cheap.
You don't have to fully charge it unless you fully drain the battery. Which on most days you probably won't. You can still plug it in when you do. With solar that just happens a little less often. Which is convenient and very practical.
In their dreams maybe, that looks more like 40W sized poly panel, and it'll never get close to that unless they're driving it along the equator with active cooling on the other side.
You rarely use 100% of the battery on these things because they are heavy to pedal manually. Range anxiety makes most people use 80% at most daily. I have few Rad Runners at home and they basically never run below 20%.
Some long tail cargo bikes have smaller back wheel to keep the center of gravity lower when carrying cargo. I’ve seen small back and normal front, or both small like with the RadPower 4 this is based on.
For a bike with a more reasonable solar area (with tilt functionality) for a significant contribution to motive power, check out https://ebikes.ca/suntrip.html
That is a great design configuration. I've seen a few models like this at Burning Man. Great mix of cargo, charging, balance, speed, etc. I was so inspired by seeing them I wrote a paper designing an entire town based around vehicles like this :)
I mean except for the 2nd passenger with rowing & leg press interface, that's......forward thinking!
The Lightyear One [1] is supposed to be a solar powered car but I think it misses an important distinction. Cars spend a lot of time parked and during this time they can unfold a large capacity of solar panels like petals of a flower (similar to how spacecraft deploy once they leave the fairing). You can cover the windshield and all the other windows, for example.
Instead, the Lightyear One has focused on streamlining the solar panels in an aerodynamic way that doesn't take advantage of extra power when parked.
Hopefully eBikes/scooters will start to standardize their charging interfaces. If I am not mistaken the new USB-C PD standard can pump out 240W(48V) and the older PD standard can do 100W(20V). I think that would be the most obvious solution, and with the new USB PD standard going up to 48v, that would cover most models without any extra voltage regulation circuitry.
I semi recently moved from small town Canada to big city Europe and decided to go car free and just use an electric scooter. If I could plug it in (and not have to lug around a charger) and lock it up somewhere, that would be amazing. I get about 15k-20km per charge, which is more or less perfect since I can go anywhere in the city and back home, but it would be nice to top up on some occasions.
Yes top up charging would be great! I frequently do 90km runs on my ebike and it would be great not having to worry. Also it would make it easier for me to loiter in shopping areas and such. I believe 240W charge is too little considering the motor usually draws atleast that. I have always thought high speed charge should be thing.
Yeah, the higher the speed the better! My current scooter (Xiaomi M365 Pro 2) only charges at 80 watts, though. The charger is rated for 42V output, which I believe means it's a 36V battery. I'm not very knowledgeable on the eBike side of things but a quick look at Bosch's site shows they seem to do 4A or 6A "fast" charging on their 36V batteries. 424=168 or 426=252Watts, so it seems like PD 3.1 could charge at regular speeds and at about 90% of fast charge speeds. Not bad, really!
Suntrip has had lots of great ones. I love Justin and Anne-Sophie's rig from a few years ago: https://www.youtube.com/watch?v=XIMM25unnU8 . If you check their channel, their small company does bespoke conversion work and they profile/demo some other interesting riders too.
Nice demonstration of what efficient mobility can look like even without hi tech light materials etc.
You could put more panels on the sides. I wonder if there's a two sided panel that could take sunlight from either side, you could have it on one side only and get the light through the wheel and spokes from the other side depending how it's facing.
Having ridden bikes for errands all my life that bike is way too heavy and lacks all agility needed to ride the broken poorly-maintained roads these days with super heavy cars and SUVs (with drivers barely paying attention at all).
Bike also doesn't have suspension. You will feel everything with all that weight.
Never put weight on the front wheel inhibiting fast turns and reaction time.
Electric Tut-Tut with pedals might be more practical if ever allowed in bike lanes
If he is using it to ferry children to and fro, I suspect he is prioritizing routes with significantly less risk of road hazards and heavy traffic. More pleasure-craft than ultimate utility.
I've not tested this specific one, but the balloon tires you see nowadays (Schwalbe Big Ben/Big Apple or similar) provide a pretty good amount of suspension and handle well on rough surfaces. Small wheels will be an issue if you're dealing with potholes. Agility is not going to save you with a passenger, so don't rely on that in the first place.
Question about ebike controllers to anyone who knows. It seems odd that upgrading the controller would necessarily push more amperage through the motor; wouldn't a motor given a certain voltage simply pull amperage based on its internal resistance, so long as the controller was able to supply the power?
great question! I work on servo controllers, so I can talk a little bit about it. The short answer is most controllers regulate current. They do these by driving at varying levels of voltage, measuring the resulting current, and using that measurement to adjust the voltage until the desired current is attained. So the relative resistance of the motor doesn't matter much with respect to how much current will flow through it.
In this case, I would assume the upgraded controller is able to drive a higher voltage in order to attained the increased current. The smaller controller likely has smaller, cheaper power transistors and related components, so it must limit itself to the maximum current (and power and heat) those transistors can handle.
BTW, the resistance of motors these days is relatively low... They can likely not handle the full amperage from the battery for very long. They simply must use controllers to switch the current.
The reason I ask is, I'm working on an ebike that had a cheap undersized controller installed such that if I drive it at full throttle long enough, the controller overheats and shuts off. My plan was to simply upgrade to a controller with a much higher amperage rating, removing that as a concern.
But it sounds like doing this could just burn out the motor? I think I can change the software of the controller to limit maximum power output, I'll have to do that I guess.
I would not have expected a controller capable of 60A to attempt to actually force 60A through a 48V, 1000W motor if the throttle was held down; I would have expected it to apply battery-level voltage to the motor (or do an internal step up/down to a constant 48V) and simply permit the motor to draw whatever amperage it pleased at that in-spec voltage.
I appreciate the technical challenge and creativity. But is it really that "green"? The battery, the solar cells, the extra heavy frame, and in a few years when it's out of fashion, all that is trash. Sure, compared to a gasoline driven motorcycle it's maybe better for the environment after enough miles, considering the whole lifecycle. Not by much though.
But if you compare it to a reasonably light "ordinary" bike, driven by muscle power, this is nowhere near "eco". It's heavy, it's expensive, and it's not going to do much good for your health. If you want a vehicle with an engine, leave the pedals out and be honest about it. Otherwise, a classical bicycle is the better fit in many ways.
Let's forget about the solar cells (there's not that many on this bike) - e-bikes really are extremely eco-friendly. Your points are not correct and I want to point out why:
> It's expensive
It's cheap. An e-bike like this costs as much as some of the extras on a car.
> it's not going to do much good for your health
This is just incorrect - if you have an e-bike, you are way more likely to use it compared to a muscle powered bike, and you are going to ride longer distances with it. In sum, the positive health effects of using an e-bike regularily are larger than using a muscle-powered one.
> compare it to a reasonably light "ordinary" bike, driven by muscle power, this is nowhere near "eco"
if you count calories, and are on an average omnivore diet, e-bikes are actually more efficient than muscle-powered bikes. it's eco.
> leave the pedals out and be honest about it
?? not sure what you mean with honest?
> in a few years when it's out of fashion
opinion: e-bikes are not a fashion, but here to stay. it's far less trash than a car.
The gasoline-electro argument is kind of true for cars though, electric cars are not eco, just slightly better than gas cars.
It is only true for the lazy motherfuckers who wouldn't ride a bike instead.
So I'd say the presence of e-bike is a positive for the overall health of the society compared to these people owning a car. On a 1:1 case of having the choice to ride a muscular powered bike vs ebike this is different.
> It's cheap. An e-bike like this costs as much as some of the extras on a car.
Yes, if you buy a car new, and you are lucky enough to have the money and location (which is also money) to choose to buy this instead of buying a car with that extra.
In other words: it's not cheap for most people, who need a car or two anyway, and buy a second hand one.
There are many families with two cars that could drop to one car plus ebikes. The things you cannot do on an ebike can be done on the car that remains. It requires some coordination of trips because you can't just take 'your car' when you want to go someplace that needs a car, but most families are rarely in the situation where they have two such trips at the same time. YMMV of course, but if you are car dependent there is still a good change you can be a one car family.
> The things you cannot do on an ebike can be done on the car that remains
Imagine you are in the normal situation of having two parents, both driving to their jobs, and dropping one or two children to school or other activities.
If you can replace one of your cars with an e-bike, you:
- at least one of you is white collar and can work from home or have flexible hours
- live somewhere that transportation is simple for at least half of your journeys, and that half of your driving journeys can all be done by the same person
- have only one full-time worker, who has a big enough salary to cover all needs
- live in an expensive metropolis with excellent public transport
Now, my family has only one car, but we tick three of those boxes and live in a cycling-friendly city. I would never pretend that what we do is particularly doable by a large number of people.
You don't need to work form home, you only need to have a job within bike distance of home. This isn't everyone, but it is a fair number of people. Most people are in a long term marriage like relationship, and the other doesn't need to be in this situation.
I agree that there more of what you list you check, the better a bike is, but I think most people could check enough of those boxes if their tried just a little. It would be worth it for them for health reasons.
> This isn't everyone, but it is a fair number of people
As my list indicates, anyone who has this has an easier time of it, but they quite possibly paid more for their house if they live near their employer.\
> Most people are in a long term marriage like relationship
Are they? Why does this matter?
> I think most people could check enough of those boxes if their tried just a little
Most of them need relatively little effort if they have a tech job - that's my situation. They get far, far more difficult if they have a blue collar / low paying job / kids with issues / health issues of their own.
Marriage matters because with two people you can share one car, including the costs. If you need a car 10% of the time you still pay for it, so you may as well use it. However if you are married share the partners car. Odds are good that even a 10% use of a car overlaps with your partners use if you don't have some other alternative, and so most buy a second car, but a bike could cover enough transport that your remaining use doesn't overlap.
I said "marriage like" relationship. Marriage as other legal and cultural connotations that may not apply, but your relationship is still such that you can share one car.
My original case was considering a two parent family, so unless you're mentioning the case of two people and no kids, which would just be a different case entirely, I don't understand your point.
I don't understand the "cycling is for rich people" argument where it's actually the case that people with low wages are the ones that overwhelmingly do not own a car.
For some people. The distance you can go is less on a regular bike. When I was young the idea of putting a tent on my bike and camping someplace remote sounded good, but these days I actually do put that load on my bike only for very short trips.
I explicitly stated that it depends on what you compare with. Sure a car is more costly. And sure the ebike is better for your health than going by car. And sure it's less trash than a car at its end of life. But if you compare with an average commuter bicycle, the story is the opposite. I already wrote all of this, but you chose to ignore that, sadly.
My parents still have their bicycles which they bought 48 years ago and use them daily. Minor repairs over the years, but by and large the same vehicles. I want to see you use your ebike essentially unchanged 48 years from now. With the original battery obviously, and with its bluetooth controlled smartphone app. Good luck.
Where I live, the people who bought an ebike and use it daily/regularly are disproportionally people who were already using an ordinary bicycle regularly. (A local newspaper made a study in collaboration with the local university.) The thought that it transitions people from using cars to something more green and healthy is largely a myth. It transitioned people from burning 600 kcal on their commute to 100 kcal on their commute. And when it's raining they still use their car.
Well I am a fit cyclist and am still riding completely muscular bikes. Having said that when I am using my trailer with heavy cargo hilly stuff can be a challenge and especially when I am on street clothing and don't want to sweat like a pig. Right now I am living at sea level so it is not a big deal but I can see my astmatic gf wanting an electric engine to help her in the hills when going back from groceries if we couldn't afford the seaside rent and had to live farther. Same with old people, they are totally fine with a regular bicycle in the flat but add groceries and hills and it is a different subject.
E-bikes an average end up being greener and healthier[1] than regular bikes because they get used so much more often, and the ultimate eco goal is to replace car trips rather than make the biking itself as green as possible. This is because they expand the possible destinations for a bike that fit into someone's daily life in a couple of possible ways:
1) The user doesn't want to be sweaty at the destination e.g. work, dinner
2) The user doesn't want to be too tired at the destination e.g. park, gym
3) the destination is too far away for their level of fitness
4) the destination takes too long to get to (a fit person can go much faster on an e-bike)
(3) and (4) are especially important in the US where bicyclists have to contend with the distances created by car-centric design.
I had a buddy who built a solar e-bike for Burning Man; it had a sort-of roof on top, so it had room for something like four of those flexible 100 watt solar panels[1].
He told me his biggest build-regret was the solar panels. Mounting the solar panels on the bike makes everything much more complicated—which means it's more expensive and more delicate. And even if it doesn't shake itself apart, you're constantly thinking about where and how you're parking it.
The right solution for solar powered biking is to keep the solar panels off the bike, fixed in place, facing the right direction. Then you can use lots of cheap, heavy panels, and just plug the damn bike in when you get home.
Unless you're off the grid, is there any use case for the solar panel you linked?
It costs $90, not including the protection circuitry.
Even if you pay a lot for electricity (e.g. $0.35 per kWh, like in PG&E service regions), you'd need to be drawing 100W for 7 hours per day, for 365 days, before you break even.
I guess realistically you're more likely to break even after 2 years? Do these small panels 'wear out' over time, or will they work for several years?
Solar panels don't really wear out like that. It's possible that severe hail may damage these flexible, less well protected cells but you can easily expect well over a decade out of them. Most residential systems are rated for 25-30 years but can realistically last longer.
Most residential systems have a warranty for 25 years. The manufacturer guarantees that there is no significant degradation for that time. That probably means that they last a lot longer than that.
Ultimately it's a semiconductor, so it's affected by the same aging processes that transistors and LEDs undergo. Actually, LEDs and solar cells are physically the same component, just designed for opposite use cases - much like motors and generators.
You can reasonably expect it to lose less than 1% of original efficiency a year, so they should last decades.
With the range of cargo ebikes it isn't hard to get off grid. Riding a century - 100 miles (200km) - is regular achievement for normal bikes - not e-bikes. Most ebikes only have a range of 40 miles, so just the ability to get 50 miles by charging while riding can be useful. If you go camping, solar puts a campground that if more than 20 miles from you in range: so long as you can recharge while at the campground for a few days you can get back home again.
Note that none of the above is about saving money. Other than indirectly because it lets you use a bike for trips that otherwise would require a car, and cars cost a lot more money to own. The above are also uses that I have for an ebike (I don't have one, but those are potential uses making me interested in one), and solar would help make it work out.
Taking an ebike farther than the batteries range should be considered impossible. While it is possible to ride on a dead battery, the effort isn't worth it. Thus a regular bike has more range than an ebike.
E-Bike touring would be an excellent use case for this. A lot of people would love to bike tour but don't have the physical ability. I have a friend who was touring on an E-Bike because it made hauling more stuff easier and he would just recharge at each stop. A solar panel would have made a huge difference.
That rad power bike in the article is already quite shitty with the high cargo position compared to a more sensible approach to put cargo in a front bed.
This bike seems to have been designed to carry kids at the bike, not haul stuff.
That's a bit negative. Like you say, better at carrying kids than stuff (which is how I use mine), but that doesn't make it "quite shitty".
I own this bike: it's very good at carrying kids, pretty good at carrying stuff, and exceptionally good value. Rad has been shrinking the back wheel to lower cargo position as iterations progress, which is nice.
They make a front rack for it as well. But it isn't a bakfiets. But it's also about 1/4 the price.
I've owned a RadCity before and it wasn't shitty at all. The dang thing is still running after 7k miles of rough treatment and crashes. The only problem I really had is with the spoke pattern on the drive wheels. They used way too thick spokes that didn't like being bent at such a sharp angle.
I've looked into this "solar powered" solution for my heavy (Urban Arrow) cargo bike for those occasional long trips, and have always come to the conclusion that it's basically a overly costly and inconvenient idea overall.
The better solution is to lug around a charger, and failing that to simply carry around another battery to extend your range.
But the immediate problem is that extra E-Bike batteries are very expensive. Each OEM has their own little monopoly with their own chargers and customized plugs, and charges through the nose for replacements.
My E-bike uses a Bosch, and e.g. [1] has replacement cells for it that retail at 1/3 or even 1/4 of the full battery pack of the same capacity. The casing, charge controller etc. should add some cost, but not that much.
I think a much more practical solution is to work on bridging that gap, another commentator commented out that USB PD is stepping up to the 48v range from 20v.
But E-Bike batteries are so expensive that even if you had to carry everything with you to up-voltage portable batteries to 220v, carry the OEM charger, and then plug it into a portable standard outlet you might still come way ahead v.s. buying another OEM battery.
Essentially you're looking for something like that: https://de.ecoflow.com/products/river-2-max-portable-power-s... - but the price point is in a similar range, and the package is substantially more chunky (inverter, ...). The issue is that I could not find any charger for bosch bike batteries that would work of USB-C PD. That would essentially cut down the package - no need for an inverter, ...
Yes, the space sucks. I'd spend significant money on a USB-C charger, but Bosch doesn't offer one and there's no third party vendors. One thing that might be of interest to you, depending on where you travel around might be this: A standardized charging cable that plugs into existing charging stations https://bike-energy.com/ueber-uns/, so you only need to carry the cable. Some adventurous folks even hacked up a cable that plugs into car charging stations.
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[ 2.7 ms ] story [ 202 ms ] threadNot quite what I expected when I read the title.
Btw, the panel is 50W, and I assume the battery is stock, 672 Wh. That's 14+ hours of best-case sunlight to recharge fully. I wonder how practical is it.
My personal preferred way to do this would be to have a stationary battery to charge up, and better solar panel positioning like you say, but that costs a bit more for that stationary battery. And if the only thing that battery/solar setup is used for is charging the bike, and you don't actually need more power then all that extra power is just gonna go to waste.
Still a fun project though, and not something I built to make a return on.
Modern fridges are often inverter drive, so should be easier to incorporate a DC power source. And they generally run all the time because they do variable-frequency drive.
Best part, it keeps working during power outages. Extra points for putting on a USB charging port (only works during the day, but still!).
If you leave the bike out in the sun all day, you can probably add 10-15 miles of range, which would be practical for some people (not everyone of course, but for many people, an e-bike wouldn't be practical even with infinite range).
But yeah 7-10mi realistically in most of the US or 5mi in the winter. That's not terrible, but it does require pretty perfect alignment and no shaddowing.
In a pedelec after a certain point you and the battery are working together to maintain speed and it really doesn't take much battery. But there are so many variables that it's hard to talk about it meaningfully.
Storing the bike outdoors continuously in the sun, wears on the condition considerably faster than indoors.
Having the solar panel attached makes for "all in one" articles, but seems rather limited on practicality for most people.
Then you can bring your bike inside, in the shade, etc. — not having to always find sunlight to park in.
The only way bringing the solar panel with the bike makes sense is a multi-day ride. But as is being pointed out, you're going to be spending a lot more time sunbathing rather than biking under power.
The cost figures in this article about [rooftop,] wind do not take into account latest gen [Dyneema] ultralight rooftop solar:
"Rooftop wind energy innovation claims 50% more energy than solar at same cost" (2022) https://pv-magazine-usa.com/2022/10/14/rooftop-wind-energy-i...
> The scalable, “#motionless” #WindEnergy unit can produce 50% more energy than rooftop solar at the same cost, said the company.
> The technology leverages aerodynamics similar to #airfoils in a race car to capture and amplify each building’s airflow. The unit requires about 10% of the space required by solar panels and generates round-the-clock energy. Aeromine said unlike conventional wind turbines that are noisy, visually intrusive, and dangerous to migratory birds, the patented system is motionless and virtually silent.
> An #Aeromine system typically consists of 20 to 40 units installed on the edge of a building facing the predominant wind direction. The company said the unit can minimize energy storage capacity needed to meet a building’s energy needs, producing energy in all weather conditions. With a small footprint on the roof, the unit can be combined with rooftop solar, providing a new tool in the toolkit for decarbonization and energy independence.
"18 Times More Power: MIT Researchers Have Developed Ultrathin Lightweight Solar Cells" (2022) https://scitechdaily.com/18-times-more-power-mit-researchers... :
> When they tested the device, the MIT researchers found it could generate 730 watts of power per kilogram when freestanding and about 370 watts-per-kilogram if deployed on the high-strength Dyneema fabric, which is about 18 times more power-per-kilogram than conventional solar cells.
> “A typical rooftop solar installation in Massachusetts is about 8,000 watts. To generate that same amount of power, our fabric photovoltaics would only add about 20 kilograms (44 pounds) to the roof of a house,” he says.
> They also tested the durability of their devices and found that, even after rolling and unrolling a fabric solar panel more than 500 times, the cells still retained more than 90 percent of their initial power generation capabilities.
E.g. Hyperlite Mountain Gear sells Dyneema ultralight backpacking packs and coats. There are Dyneema Patch Kits that work for various types of gear.
Wise to look at Ultralight backpacking gear before buying regular camping gear. Solarcore Aerogel is warm and light and also in encased in PVA foam rubber which is like a new wet suit. https://twitter.com/westurner/status/1600820322567041024 Kayaking bags are waterproof, but are there yet Dyneema ones?
730-370 watts/kilogram is the number to beat (for DIY electric bicycle applications)
And rooftop wind is competitive (for charging offline batteries)
Presumably, bicycling is like ultralight hiking: wHr/kg is the or a limit https://en.wikipedia.org/wiki/Kilowatt-hour
A pedaling electric bicycler could tow a solar wagon, eh
I guess the sensible way would be just having bigger, fold down solar panel array and to deploy it where you stop.
Things may work out if you plan on having a stationary camp somewhere remote.
There are no easy answers.
Also, the electronics are mounted out in the open and on top of a small bit of wood, that works well in the lab but if you're going to be biking and end up being rained on it may well cause issues, just using splash proof connectors isn't enough, you need to protect the electronics from the elements by eliminating direct contact with the elements. Much like in a car: all of the connectors under the hood are waterproof and they are under the hood, not out in the weather.
That said, it's a neat idea.
Source: I cushion my robots this way, haven't gotten to the ebike yet.
On the whole it isn't perfect but good enough for many years, I've run this setup for a year now and have once (at 5K km) inspected the wiring and the battery welds and everything seems to be holding up quite well. Things to be careful with: overpressuring the tires would reduce the amount of shock absorbing capacity quite a bit (and is definitely not recommended with tires this wide anyway), the rolling resistance of these is fairly high but that is just how they are designed. Then, obviously there is bumping in to things and falling at speed, which fortunately hasn't happened. But if it did I would immediately consider the battery pack a write-off in spite of being super well protected. I've done about 10K on it now and when it hits 20 I'll take the whole thing apart to see if there is any wear that is hidden from view. I'm mostly concerned with the battery welds and the wiring, those are the weak points, even with all of the wiring contained within the enclosure, routed carefully to never cross over any other wires and with the welds checked using a FLIR during a pretty rapid discharge (twice as fast as the motor could ever do).
The OP has mounted the charge controller and the motor controller to a piece of wood (which will flex a bit but not much) which in turn appears to be protected in only one axis (side-to-side) and is either free to move or rigid in the other two. The wiring runs 'cold' without any kind of extra protection through the wood that it is mounted on. The frame is unsprung as far as I can tell, which especially for the front is not a luxury on a bike this heavy, which makes bike+battery the unsprung weight (I think I see a saddle pin with a rubber mount so there is some flex there). That battery box may have some foam in it or some other suspension for the battery which is good.
As long as he's on good asphalt this setup will work, but as soon as you go on less perfect roads I think that it will give trouble over time. DIY stuff like this looks great on the day you build it if you don't build it for abuse, but exposed wiring is dangerous and vibration as well as the weather are going to be rough on this. I'm curious what it will look like a year from now if used intensively, and also how the wire runs are on the other side of that board.
End result, everything is perfectly potted except the topside of an aluminium heatsink.
In their dreams maybe, that looks more like 40W sized poly panel, and it'll never get close to that unless they're driving it along the equator with active cooling on the other side.
So getting +50% charge in a day is not too bad.
I mean except for the 2nd passenger with rowing & leg press interface, that's......forward thinking!
Instead, the Lightyear One has focused on streamlining the solar panels in an aerodynamic way that doesn't take advantage of extra power when parked.
[1] https://lightyear.one/lightyear-0
Feels like vandalism or just accidental collisions would be real problems
I semi recently moved from small town Canada to big city Europe and decided to go car free and just use an electric scooter. If I could plug it in (and not have to lug around a charger) and lock it up somewhere, that would be amazing. I get about 15k-20km per charge, which is more or less perfect since I can go anywhere in the city and back home, but it would be nice to top up on some occasions.
You could put more panels on the sides. I wonder if there's a two sided panel that could take sunlight from either side, you could have it on one side only and get the light through the wheel and spokes from the other side depending how it's facing.
Bike also doesn't have suspension. You will feel everything with all that weight.
Never put weight on the front wheel inhibiting fast turns and reaction time.
Electric Tut-Tut with pedals might be more practical if ever allowed in bike lanes
https://electrek.co/2023/02/02/i-bought-electric-rickshaw-tu...
In this case, I would assume the upgraded controller is able to drive a higher voltage in order to attained the increased current. The smaller controller likely has smaller, cheaper power transistors and related components, so it must limit itself to the maximum current (and power and heat) those transistors can handle.
BTW, the resistance of motors these days is relatively low... They can likely not handle the full amperage from the battery for very long. They simply must use controllers to switch the current.
The reason I ask is, I'm working on an ebike that had a cheap undersized controller installed such that if I drive it at full throttle long enough, the controller overheats and shuts off. My plan was to simply upgrade to a controller with a much higher amperage rating, removing that as a concern.
But it sounds like doing this could just burn out the motor? I think I can change the software of the controller to limit maximum power output, I'll have to do that I guess.
I would not have expected a controller capable of 60A to attempt to actually force 60A through a 48V, 1000W motor if the throttle was held down; I would have expected it to apply battery-level voltage to the motor (or do an internal step up/down to a constant 48V) and simply permit the motor to draw whatever amperage it pleased at that in-spec voltage.
But if you compare it to a reasonably light "ordinary" bike, driven by muscle power, this is nowhere near "eco". It's heavy, it's expensive, and it's not going to do much good for your health. If you want a vehicle with an engine, leave the pedals out and be honest about it. Otherwise, a classical bicycle is the better fit in many ways.
> It's expensive
It's cheap. An e-bike like this costs as much as some of the extras on a car.
> it's not going to do much good for your health
This is just incorrect - if you have an e-bike, you are way more likely to use it compared to a muscle powered bike, and you are going to ride longer distances with it. In sum, the positive health effects of using an e-bike regularily are larger than using a muscle-powered one.
> compare it to a reasonably light "ordinary" bike, driven by muscle power, this is nowhere near "eco"
if you count calories, and are on an average omnivore diet, e-bikes are actually more efficient than muscle-powered bikes. it's eco.
> leave the pedals out and be honest about it
?? not sure what you mean with honest?
> in a few years when it's out of fashion
opinion: e-bikes are not a fashion, but here to stay. it's far less trash than a car.
The gasoline-electro argument is kind of true for cars though, electric cars are not eco, just slightly better than gas cars.
That might be true for someone, but it's a bit of a leap in general
So I'd say the presence of e-bike is a positive for the overall health of the society compared to these people owning a car. On a 1:1 case of having the choice to ride a muscular powered bike vs ebike this is different.
What prevents people from biking is mostly weather: cold/hot, rain. Neither are fixed by an ebike.
When it's chilly, an ebike is actually worse. You heat up less and go faster, so more windchill.
Yes, if you buy a car new, and you are lucky enough to have the money and location (which is also money) to choose to buy this instead of buying a car with that extra.
In other words: it's not cheap for most people, who need a car or two anyway, and buy a second hand one.
Imagine you are in the normal situation of having two parents, both driving to their jobs, and dropping one or two children to school or other activities.
If you can replace one of your cars with an e-bike, you:
- at least one of you is white collar and can work from home or have flexible hours
- live somewhere that transportation is simple for at least half of your journeys, and that half of your driving journeys can all be done by the same person
- have only one full-time worker, who has a big enough salary to cover all needs
- live in an expensive metropolis with excellent public transport
Now, my family has only one car, but we tick three of those boxes and live in a cycling-friendly city. I would never pretend that what we do is particularly doable by a large number of people.
I agree that there more of what you list you check, the better a bike is, but I think most people could check enough of those boxes if their tried just a little. It would be worth it for them for health reasons.
As my list indicates, anyone who has this has an easier time of it, but they quite possibly paid more for their house if they live near their employer.\
> Most people are in a long term marriage like relationship
Are they? Why does this matter?
> I think most people could check enough of those boxes if their tried just a little
Most of them need relatively little effort if they have a tech job - that's my situation. They get far, far more difficult if they have a blue collar / low paying job / kids with issues / health issues of their own.
I said "marriage like" relationship. Marriage as other legal and cultural connotations that may not apply, but your relationship is still such that you can share one car.
My parents still have their bicycles which they bought 48 years ago and use them daily. Minor repairs over the years, but by and large the same vehicles. I want to see you use your ebike essentially unchanged 48 years from now. With the original battery obviously, and with its bluetooth controlled smartphone app. Good luck.
Where I live, the people who bought an ebike and use it daily/regularly are disproportionally people who were already using an ordinary bicycle regularly. (A local newspaper made a study in collaboration with the local university.) The thought that it transitions people from using cars to something more green and healthy is largely a myth. It transitioned people from burning 600 kcal on their commute to 100 kcal on their commute. And when it's raining they still use their car.
1) The user doesn't want to be sweaty at the destination e.g. work, dinner
2) The user doesn't want to be too tired at the destination e.g. park, gym
3) the destination is too far away for their level of fitness
4) the destination takes too long to get to (a fit person can go much faster on an e-bike)
(3) and (4) are especially important in the US where bicyclists have to contend with the distances created by car-centric design.
[1] https://electrek.co/2019/08/11/electric-bike-riders-more-exe...
He told me his biggest build-regret was the solar panels. Mounting the solar panels on the bike makes everything much more complicated—which means it's more expensive and more delicate. And even if it doesn't shake itself apart, you're constantly thinking about where and how you're parking it.
The right solution for solar powered biking is to keep the solar panels off the bike, fixed in place, facing the right direction. Then you can use lots of cheap, heavy panels, and just plug the damn bike in when you get home.
[1] for example: https://www.amazon.com/Flexible-Monocrystalline-Bendable-Sem...
It costs $90, not including the protection circuitry.
Even if you pay a lot for electricity (e.g. $0.35 per kWh, like in PG&E service regions), you'd need to be drawing 100W for 7 hours per day, for 365 days, before you break even.
I guess realistically you're more likely to break even after 2 years? Do these small panels 'wear out' over time, or will they work for several years?
You can reasonably expect it to lose less than 1% of original efficiency a year, so they should last decades.
Note that none of the above is about saving money. Other than indirectly because it lets you use a bike for trips that otherwise would require a car, and cars cost a lot more money to own. The above are also uses that I have for an ebike (I don't have one, but those are potential uses making me interested in one), and solar would help make it work out.
This bike seems to have been designed to carry kids at the bike, not haul stuff.
I own this bike: it's very good at carrying kids, pretty good at carrying stuff, and exceptionally good value. Rad has been shrinking the back wheel to lower cargo position as iterations progress, which is nice.
I've owned a RadCity before and it wasn't shitty at all. The dang thing is still running after 7k miles of rough treatment and crashes. The only problem I really had is with the spoke pattern on the drive wheels. They used way too thick spokes that didn't like being bent at such a sharp angle.
I wonder if there's progress on thin film PV, so that you could have flexible bike solar body.
The better solution is to lug around a charger, and failing that to simply carry around another battery to extend your range.
But the immediate problem is that extra E-Bike batteries are very expensive. Each OEM has their own little monopoly with their own chargers and customized plugs, and charges through the nose for replacements.
My E-bike uses a Bosch, and e.g. [1] has replacement cells for it that retail at 1/3 or even 1/4 of the full battery pack of the same capacity. The casing, charge controller etc. should add some cost, but not that much.
I think a much more practical solution is to work on bridging that gap, another commentator commented out that USB PD is stepping up to the 48v range from 20v.
But E-Bike batteries are so expensive that even if you had to carry everything with you to up-voltage portable batteries to 220v, carry the OEM charger, and then plug it into a portable standard outlet you might still come way ahead v.s. buying another OEM battery.
1. https://www.aliexpress.com/item/33047384848.html
You'd need to stop to charge, but that's usually not an issues on longer trips.
It's insane that this is even a viable option, but that's how overpriced these batteries are.