6 ms·

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

by theamk 4y ago

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.

jillesvangurp 4y ago
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.
sandworm101 4y ago
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.
- poopbutt7 4y ago
  Agreed- another waste of space on the front page. This hobbyist should be embarrassed by their folly.
- deleted 4y ago
  [deleted]
- ThatPlayer 4y ago
  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.
  - fomine3 4y ago
    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.
    - ThatPlayer 4y ago
      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.
  - Scoundreller 4y ago
    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!).
    - fbdab103 4y ago
      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.
      - irq 4y ago
        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).
- Rebelgecko 4y ago
  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.
  - ilyt 4y ago
    The problem is that the way it was done looks pretty inconvenient with panel being high up and potentially in the way
- renewiltord 4y ago
  Hobby DIY is a fun thing for many people to try. But spending all your time online is often more important than building.
jonas21 4y ago
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).
- kurthr 4y ago
  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.
ehnto 4y ago
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.
irjustin 4y ago
Feels like it would be better to have 2 batteries, dedicated charging "shed", and fast swap ability? 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.
- Gigachad 4y ago
  It always is. But people get so stuck on this idea of lugging the panel around with you for some reason.
JKCalhoun 4y ago
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.
- westurner 4y ago
  <wagon in tow> Yeah, Good call boss. 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-innovation-claims-50-more-energy-than-solar-at-same-cost/ 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-have-developed-ultrathin-lightweight-solar-cells/ 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 https://twitter.com/westurner/status/1600820322567041024 Kayaking bags are waterproof, but are there yet Dyneema ones?
Schroedingersat 4y ago
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.
jacquesm 4y ago
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. That said, it's a neat idea.
- andreareina 4y ago
  How did you manage the shocks? I've been thinking about a conversation for my commuter (more for the diy aspect than really wanting an electric)
  - Hextinium 4y ago
    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.
    - jacquesm 4y ago
      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.
  - jacquesm 4y ago
    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.
discordance 4y ago
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.
moffkalast 4y ago
> Btw, the panel is 50W 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.
clnq 4y ago
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%. So getting +50% charge in a day is not too bad.

by theamk 4y ago

jillesvangurp 4y ago

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.

sandworm101 4y ago

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.

poopbutt7 4y ago
Agreed- another waste of space on the front page. This hobbyist should be embarrassed by their folly.
deleted 4y ago
[deleted]
ThatPlayer 4y ago
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.
- fomine3 4y ago
  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.
  - ThatPlayer 4y ago
    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.
- Scoundreller 4y ago
  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!).
  - fbdab103 4y ago
    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.
    - irq 4y ago
      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).
Rebelgecko 4y ago
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.
- ilyt 4y ago
  The problem is that the way it was done looks pretty inconvenient with panel being high up and potentially in the way
renewiltord 4y ago
Hobby DIY is a fun thing for many people to try. But spending all your time online is often more important than building.

jonas21 4y ago

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).

kurthr 4y ago
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.

ehnto 4y ago

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.

irjustin 4y ago

Feels like it would be better to have 2 batteries, dedicated charging "shed", and fast swap ability? 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.

Gigachad 4y ago
It always is. But people get so stuck on this idea of lugging the panel around with you for some reason.

JKCalhoun 4y ago

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.

westurner 4y ago
<wagon in tow> Yeah, Good call boss. 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-innovation-claims-50-more-energy-than-solar-at-same-cost/ 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-have-developed-ultrathin-lightweight-solar-cells/ 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 https://twitter.com/westurner/status/1600820322567041024 Kayaking bags are waterproof, but are there yet Dyneema ones?

Schroedingersat 4y ago

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.

jacquesm 4y ago

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. That said, it's a neat idea.

andreareina 4y ago
How did you manage the shocks? I've been thinking about a conversation for my commuter (more for the diy aspect than really wanting an electric)
- Hextinium 4y ago
  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.
  - jacquesm 4y ago
    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.
- jacquesm 4y ago
  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.

discordance 4y ago

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.

moffkalast 4y ago

> Btw, the panel is 50W 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.

clnq 4y ago

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%. So getting +50% charge in a day is not too bad.