Re: Around the world on a solar ebike
Posted: Jun 05 2019 5:48pm
Electric Vehicle and Technology Forums
Very nice. I like the simplicity of the 3D printed mounts. How have they held up over time? Have you noticed any reduction in solar power from the cells cracking as the panel flexes?
I found the nuts/bolts have loosened slightly over time, but the shape of the mounts has stayed the same so far.
Sorry, I'm struggling to unpack this sentence...
solarEbike wrote: ↑Jun 10 2019 2:37pmAlso, I currently only have the 88 watt roof panel plus a small 50 watt test panel on the trailer so I never have enough solar to charge the battery while riding. I prefer to always use some assist. But when the trailer is complete, I'll have a total of 330 watts of solar panels (maybe 250-300 watts actual) so there will be times when I can cruise at a good speed and still (slowly) charge the battery.
Oh I see now, there are 10 fixed LEDs that represent the state of charge! That makes sense now naturally.solarEbike wrote: ↑Jun 10 2019 2:37pmSorry, I'm struggling to unpack this sentence...
One or two green LEDs would be 10-20% SoC.
I understand the confusion now. I posted a couple of different photos showing different ideas I tried out along the way and didn't fully explain. Initially, I used all 16 LEDs to represent battery SoC and later I changed it to just the 10 LEDs on the right. Each LED represents 10% but since I can create any color between red and green, the LED between red and green slow changes from green to red as the battery discharges. I can't quite visually differentiate between 10 different shades but I can read the SoC within 2-3% rather than have the meter jump in 10% increments if the meter LEDs were only red or green.thundercamel wrote: ↑Jun 11 2019 11:02amOh I see now, there are 10 fixed LEDs that represent the state of charge! That makes sense now naturally.
I was thinking that you were doing something more advanced, like red + green LEDs equaled the state of charge, but then green represented how much was estimated to be remaining when you reached your destination at the current level of discharge. More solar and more pedaling would increase the green bars in real time, less solar and more throttle would decrease the green bars in real time.
I've purchased 8 or 10 different semi-flexible frameless solar panels over the years for my bike projects. These are easily the best option for 95% of solar bike builders. There are lots of options on the market in the $1-2/watt price range. Stay away from the low end of the price range and try to find a vendor who has been in business for a long time. Ideally, they will take the panel back if it doesn't perform as advertised. Unfortunately, many of these panels do not deliver on their published specifications and, I suspect, most buyers never know the difference because they are not using a watt meter and don't know how to account for cell temperature and irradiance when evaluating the output they're getting.ScooterMan101 wrote: ↑Jun 10 2019 5:35pmAre you going to buy a couple of commercial flexible solar panels ? ( if so which ones and from where )
Are you going to make your own panel ?
You make your own panel what cells are you going to use ?
What is the cost of each cell ? Strips and solder , taxes and shipping costs ?
On what material will you be gluing the cells to ? ( something that does not contract and expand with the different temps during the day and night )
I haven't discussed the bike much because the solar conversion and long distance touring could be done with just about any bike. Also, it's just a commercial thing I bought as opposed to something that took some creative problem solving, which is my real interest. However, I do get a lot of general recumbent questions. Sometimes, I'll get a stranger asking me about the recumbent and we'll be talking for 10 minutes before the topic of electric conversion and solar power comes up and then they'll notice that the funny looking roof is in fact a solar panel.thundercamel wrote: ↑Jul 03 2019 10:31amI went through this thread again, and I don't think you've discussed your bike frame at all. It started off with a 26" wheel in the back, and then switched to one with 20" wheels front and back. I had assumed you put the motor in the front for the higher efficiency at higher rpm, but what made you keep it in the front now? Possibly keeping a nice gear arrangement in the back?
Under-seat steering is common on trikes but much less common on two-wheeled recumbents. I think I stuck with it because I was used to it from the original trike. I like the relaxed hand position at my sides as opposed to the "praying hamster" pose of the above seat steering. For a racing recumbent, above seat makes more sense as it's more aerodynamic. I think the under seat option for touring recumbents is less common because people find it intimidating to learn? After the first few miles, you get used to it.thundercamel wrote: ↑Jul 03 2019 10:31amI've decided that I want my next bike to be like yours except with a mesh seat, but I'm having a hard time finding stores that sell them. Plenty of trikes, some sell overhead steering or a model with a 26" rear wheel, some used ones on craigslist without suspension, but I haven't found a store yet that sells the whole package I want like this.
Hmm... I've been riding around with it for a while now and I haven't noticed anything that negatively affects the bike's handling. You're probably right that there's some lift/drag going on. The original cardboard prototype folded over like a taco in a wind gust.