Is anyone trying to solve charging on the road?

When it comes to Solar generally, you get what you pay for. And my advice is to do some math on all the losses with solar. Also even the most expensive, highest quality 175W panel will rarely output 175W, except for when there's no clouds and you're on top of Mt. Everest :)
My SunCapture 300W charges my packs to 56.8 volts easily even on a bright overcast day... even at sea level.

SunCapture 300W Solar Panel & Grin Adjustable DC/DC Converter.
https://photos.app.goo.gl/rFim5rPsajmDt8NJ6
 
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Seriously the most informative post Ive seen on EBR, at least when I can follow the arguements. Battery University is a good general resource, but not much help for the specifics on charging on the road. Thanks to all who participated.
Art
 
My ride: 1 yr. old Bosch CX class 1 w/500 watt battery. Just ordered a second 500 watt battery @ $850 rather than upgrading to a new 1000 watt dual battery bike.
My goal: Before I’m on “my last lap” (I’ve been 70 yrs old for awhile), I want to duplicate a cross country self-contained ride I did many yrs. ago. Only-No cooking—just buying stuff along the way. Rear panniers (carrying second battery)+ handlebar bag.
My thoughts: IF I could ride 12-16 mph range, mainly eco & touring mode-daily mileage 70-85 miles-using a stock 4 amp charger. Batteries will be rotated every hr. or two. Charging at hotels & campgrounds at night.
If everything holds up, I figure around 6 weeks, about 3,300 miles total, give or take ...
Does this sound doable ? Am I missing something ?
 
My ride: 1 yr. old Bosch CX class 1 w/500 watt battery. Just ordered a second 500 watt battery @ $850 rather than upgrading to a new 1000 watt dual battery bike.
My goal: Before I’m on “my last lap” (I’ve been 70 yrs old for awhile), I want to duplicate a cross country self-contained ride I did many yrs. ago. Only-No cooking—just buying stuff along the way. Rear panniers (carrying second battery)+ handlebar bag.
My thoughts: IF I could ride 12-16 mph range, mainly eco & touring mode-daily mileage 70-85 miles-using a stock 4 amp charger. Batteries will be rotated every hr. or two. Charging at hotels & campgrounds at night.
If everything holds up, I figure around 6 weeks, about 3,300 miles total, give or take ...
Does this sound doable ? Am I missing something ?
Many factors beyond what you mentioned:
 
My ride: 1 yr. old Bosch CX class 1 w/500 watt battery. Just ordered a second 500 watt battery @ $850 rather than upgrading to a new 1000 watt dual battery bike.
My goal: Before I’m on “my last lap” (I’ve been 70 yrs old for awhile), I want to duplicate a cross country self-contained ride I did many yrs. ago. Only-No cooking—just buying stuff along the way. Rear panniers (carrying second battery)+ handlebar bag.
My thoughts: IF I could ride 12-16 mph range, mainly eco & touring mode-daily mileage 70-85 miles-using a stock 4 amp charger. Batteries will be rotated every hr. or two. Charging at hotels & campgrounds at night.
If everything holds up, I figure around 6 weeks, about 3,300 miles total, give or take ...
Does this sound doable ? Am I missing something ?

You might want to check how long it takes to charge 2 batteries with a single charger. My 4 amp charger takes 4 - 5 hours to charge a single 720 watt battery. I got tired of getting up in the middle of the night to switch the charger to the second battery. I now carry two chargers. The second is also a backup if one fails.
 
...
Does this sound doable ? Am I missing something ?

At a very high level this is very doable.

In easy and gentle terrain, with no headwinds, and very good road surfaces you should easily make those mileages with two batteries and only rarely need to top up the batteries during the day. So a lot depends on the route you plan to take.

If you are riding in mountains but still mostly on pavement 55-65 miles is probably more realistic.
 
At a very high level this is very doable.

In easy and gentle terrain, with no headwinds, and very good road surfaces you should easily make those mileages with two batteries and only rarely need to top up the batteries during the day. So a lot depends on the route you plan to take.

If you are riding in mountains but still mostly on pavement 55-65 miles is probably more realistic.
Points well taken. I’ll reconsider a second charger (which I wanted to avoid) & re-think daily mileage.
The only mountains I have here (south Fl.) are a few bridges.
I appreciate your advice.
Thank you all
 
The Bosch "Compact" charger (100-240VAC, 2A), new is about 2/3 of the price of the "Standard" charger (4A), approx 200 grams lighter and will get a flat 500Wh to 85-90% in about 6 hours with an additional 1-1.5 hours to get to 100%.
 
My SunCapture 300W charges my packs to 56.8 volts easily even on a bright overcast day... even at sea level.
Your SunCapture 300 weighs 17 lbs (7.71kg), folds up to 22"x16"x3" (56x41x7.6cm), is 946 cubic inches (15.5 litres) in volume folded!, costs US$2500 and i'm sure it works well being Sunpower cells.

I wanted something smaller & more modular for around the 100-150W mark so i bought 2 x P3 Solar P125W's & made up my own parallel cable: https://p3solar.com/portfolio/p3-125/
Each one cost US$880 (much more to get to Australia), in decent Oz sun each one output's 113W, each folds up to about 32x26x4.5cm (12.5"x10.25"x1.77") & each one weighs 1.86kg (4.1 lbs), so 3.72kg (8.2 lbs) for the 2. About 9.4 litres (574 cubic inches) of volume for the 2.
But each one fit's neatly inside one of these: https://www.ortlieb.com/gravel-pack
And if one fails badly (even though they're tough as) i have another to fall back on, also if it's super sunny i just use one or if i couldn't be bothered moving them every 3 hours or so then i deploy the 2. In fact when in the Ozzie summer i usually only need one.

That's enough unit conversion from me for a while! :)
 
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Currently working on a bigger buffer battery between my panels and ebike charging equipment. From 2.5Ah @ 13.2VDC (33Wh, weighs 460g) to 20Ah @ 13.2VDC (264Wh, approx 2kg).
This should allow much more room to move in really bad sunlight, and a large powerbank for charging other devices at night and maybe some light charging on the road.
And because it's LifePO4 chemistry, it can be charged rapidly, safely.
But i just got burned from an Aliexpress supplier with 4 x 3.2V 10Ah pouch cells - supposed to be new but are definitely second hand and will try for full refund. Then make no mistakes and spend the money on more reliable sources & get reliable A123 brand 3.3V 20Ah pouch cells :)
If all goes well i should have a new 23x16.5x3cm self made battery soon, odd shape though and will have to take care of not to squash/bend/etc as it won't be in a hard case :)
 
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My ride: 1 yr. old Bosch CX class 1 w/500 watt battery. Just ordered a second 500 watt battery @ $850 rather than upgrading to a new 1000 watt dual battery bike.
My goal: Before I’m on “my last lap” (I’ve been 70 yrs old for awhile), I want to duplicate a cross country self-contained ride I did many yrs. ago. Only-No cooking—just buying stuff along the way. Rear panniers (carrying second battery)+ handlebar bag.
My thoughts: IF I could ride 12-16 mph range, mainly eco & touring mode-daily mileage 70-85 miles-using a stock 4 amp charger. Batteries will be rotated every hr. or two. Charging at hotels & campgrounds at night.
If everything holds up, I figure around 6 weeks, about 3,300 miles total, give or take ...
Does this sound doable ? Am I missing something ?
I’ve done it, it’s doable. If you’ve planned things out for a guaranteed outlet nightly, you’ll probably do some charging over lunch. Actual mileage depends on your route. 12-16 mph seems reasonable, doubt you’ll sit in eco most of the time with any kind of load. Feel free to hit my inbox if you have questions.

Here is my question for you. This summer? I‘m leaning to no. Spigots turned off, campgrounds at capacity due to distancing rules, public restrooms closed, places to charge (even with buying lunch) looking for quick turnaround due to distancing, and so on.

I’ll add some less obvious things. High unemployment. Petty theft was a problem already in some areas last summer. Towns with meatpacking plants/hog farms and the like that account for a high proportion of COVID in midwestern states. A lot of research needed!
 
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The Bosch "Compact" charger (100-240VAC, 2A), new is about 2/3 of the price of the "Standard" charger (4A), approx 200 grams lighter and will get a flat 500Wh to 85-90% in about 6 hours with an additional 1-1.5 hours to get to 100%.
Great idea !!! What a great option . . .thx for info
 
SunCapture 300W folding panel w/MPPT controller. Add an adjustable dc/dc converter and charge anything from 3 to 33vdc in addition to the main batteries.

20200626_110001.jpg


https://photos.app.goo.gl/rFim5rPsajmDt8NJ6
 
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So I'm attempting to ride up the Southern California coast, some hotels, hopefully some campgrounds, probably some wild camping, and as much solar charging as I can fit in. I have a Renogy 160w panel and an MPT-7210a charge controller to charge my 17.2ah 48v bike battery, and my 18ah 36v trailer battery. Round one, I made it about 220 miles before I had technical difficulties, but once the holiday weekend is over I'm going to head out again.

IMG_20200629_173720731_HDR.jpg


So far the most I've been able to coax out of my system is ~87w output to the battery (what comes out of the charge controller). I'm most likely going to get a second panel; I designed my mount to be able to easily transport two (only one usable while mounted, of course). And I'm going to do some research to see how to maximize my charging while on the road.
 
So I'm attempting to ride up the Southern California coast, some hotels, hopefully some campgrounds, probably some wild camping, and as much solar charging as I can fit in. I have a Renogy 160w panel and an MPT-7210a charge controller to charge my 17.2ah 48v bike battery, and my 18ah 36v trailer battery. Round one, I made it about 220 miles before I had technical difficulties, but once the holiday weekend is over I'm going to head out again.

So far the most I've been able to coax out of my system is ~87w output to the battery (what comes out of the charge controller). I'm most likely going to get a second panel; I designed my mount to be able to easily transport two (only one usable while mounted, of course). And I'm going to do some research to see how to maximize my charging while on the road.
Nice job! How bad does the wind grab the panel? What kind of range are you getting and why no front panniers? Ride safe.
 
Very interesting tech... can you tell us more about the PV panel system?
HPC SunCapture 300W - 10 Sunpower Maxeon Gen III cells (24.2%) sewn into a nylon folding panel, 16" x 22" x 3" Folded, 78" x 44" x .18" Unfolded, 17lbs.

Pmax Voltage: ~36V, Pmax Current: ~8.30A Voc: ~ 43.2V, Isc: ~ 9.98A
N
ote: It is listed as a Pmax of 36V but the picture shows a Pmax voltage of 39.8V on the multi-meter, it wasn't a clear day, and the panel wasn't oriented toward the sun as good as it could have been.

They have been available for several years on HPCbikes.com although they don't show any 300W panels presently. A search came up with this link. ( https://www.upzy.com/products/hpc-suncapture-300-folding-solar-panel-and-charger ) It's not new technology but the cells are still way up the list on conversion capability, very durable and most importantly foldable. Cut their weight and price in half and people might buy them. I got mine for 1/2 price on Black Friday last year.
 
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