Stationary Charging a battery

Mhatayas

10 µW
Joined
Oct 31, 2019
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6
I'm building a tow behind bicycle shelter 4x8 (sheet of plywood) for my first (and if all goes well, only) ebike build.

The motor I will use will be the cyclone 3000w as it seems it will have enough tourqe to pull the drag the camper adds ( note that I have already made a camper to tow behind a peddle only bike , so I have a sense of weight /drag ratio)
And also a fun burst of speed for when I park my shelter and go about my daily order ....



I know it can be done and is practical for my needs , I plan to live in this shelter for extended periods of time (months, years) , it will have a wood stove and be fully equipped for all seasons (with fatbike wheels as the camper wheels )


Here's a few products below , that I am considering for charging the ebike battery from fully drained , to fully filled soley based on these types of energy (on their own , or combined )

What I need to know , before I go ahead and purchase anything, is what is the realistic time frame for charging the battery from fully drained to fully charged is , using these products on their own and combined (wind and solar ) , the ebike battery will be around 52v 20ah (would 72v20ah be recommended instead ?)


---- 3500W 5 Blade Wind Turbine Red White Flashlight Option Motor Kit 12 / 24V Vertical + Controller for Home Street Light,Red,24V https://www.amazon.ca/dp/B07Y2T813L/ref=cm_sw_r_cp_apa_i_zd6UDbZ9AEQ39

---- waterlilly 12V water/ windturbine (i will run two in series ) https://www.ebay.ca/i/183714165831?chn=ps&norover=1&mkevt=1&mkrid=706-89093-2056-0&mkcid=2&itemid=183714165831&targetid=607627058052&device=m&mktype=pla&googleloc=9061009&poi=&campaignid=1669215011&mkgroupid=63013116845&rlsatarget=pla-607627058052&abcId=1063836&merchantid=10252592&gclid=Cj0KCQjwjOrtBRCcARIsAEq4rW5mWmBfB953qJqRFWSPU5Jq21wtTrbtHw0g8ObYRBV_cqF83aVjjpUaAkvnEALw_wcB

----- solar panels , the highest powered and lightest panel(s)? I can get , here's are a couple suggestion

ECO-WORTHY 300W Monocrystalline 12v 24v Off Grid Battery Charging Solar Panel Kit: 2pcs 160W Mono Solar Panels+60A Charge Controller+Solar Cable+MC4 Branch Connectors Pair+Z Bracket Mounts https://www.amazon.ca/dp/B00WSLY1WM/ref=cm_sw_r_cp_apa_i_uG6UDb6VTHAYH

200w 12v Solar Panel Kit 2pcs 100W Flexible Solar Panels for RV, Boat, Cabin, Tent, Car, Trailer, 12v Battery with Solar Controller MC4 Connector Wire https://www.amazon.ca/dp/B07PVH4HYQ/ref=cm_sw_r_cp_apa_i_MF6UDbPHJZNYM

--- thermoelectric generator (bolted onto my campers wood stove , check the link )

https://www.tegmart.com/thermoelectric-generator-systems/100-watt-water-cooled-teg-sytem







I would prefer to be able to charge the battery within 24 hours atleast , based on the products listed above.

If anyone can help me out with the timeframe of battery charging from empty to full , for all of the products above would be great and would set me to the next steps of the project , I understand it takes a lot of math to figure out what I just asked but I need assistance as I don't understand the whole process yet and cannot calculate it myself ...

Sent from my Moto Z2 Play using Tapatalk

 
Mhatayas said:
---- 3500W 5 Blade Wind Turbine Red White Flashlight Option Motor Kit 12 / 24V Vertical + Controller for Home Street Light,Red,24V https://www.amazon.ca/dp/B07Y2T813L/ref=cm_sw_r_cp_apa_i_zd6UDbZ9AEQ39
Well, this one can't do what it says; it's own specs even say that:
"Maximum power: 1600 W"
Others like it are probably similarly mis-specified. (or worse)

And wind is undependable most places, so you'd need an alternate charge source as well, for when you are in a non-windy area or time. So you'd be carrying around 40lbs or more of stuff you can't use during those times.


---- waterlilly 12V water/ windturbine (i will run two in series ) https://www.ebay.ca/i/183714165831?chn=ps&norover=1&mkevt=1&mkrid=706-89093-2056-0&mkcid=2&itemid=183714165831&targetid=607627058052&device=m&mktype=pla&googleloc=9061009&poi=&campaignid=1669215011&mkgroupid=63013116845&rlsatarget=pla-607627058052&abcId=1063836&merchantid=10252592&gclid=Cj0KCQjwjOrtBRCcARIsAEq4rW5mWmBfB953qJqRFWSPU5Jq21wtTrbtHw0g8ObYRBV_cqF83aVjjpUaAkvnEALw_wcB
This one's specs
Output: DC 14.6V
Up to 2A
Up to 30W
are probably optimistic; most likely require whatever it's maximum flow rate is to reach them, at best.

I might've missed the size/weight spec, but it's probably smaller than the first one, since it's way way less capable. But it wouldn't take as much to haul it around even when you're not able to use it.




ECO-WORTHY 300W Monocrystalline 12v 24v Off Grid Battery Charging Solar Panel Kit: 2pcs 160W Mono Solar Panels+60A Charge Controller+Solar Cable+MC4 Branch Connectors Pair+Z Bracket Mounts https://www.amazon.ca/dp/B00WSLY1WM/ref=cm_sw_r_cp_apa_i_uG6UDb6VTHAYH
Probably ok, no experience with it, but it's going to be large and somewhat heavy (this is true of most of the larger panels).

The others are likely similar.

All of them will need a 12v battery to buffer the charge from the controller to whatever 12VDC to 110VAC inverter you use to plug your bike's battery charger into.

Also, that inverter will waste a significant portion of the power generated, and the bike's charger will waste some more--at a guess you'll get something like half to maybe 3/4 of the power generated by the panels into your bike battery, but I don't know what it will be for sure. You'd have to test whatever system you actually get to find out.

If you use a bike battery that is within the voltage range of various solar MPPT / etc charge controllers, you can prevent a fair bit of that power loss, by skipping both the DC-AC inverter and the charger, if you can control the amount of current the charge controller outputs so it doens't exceed your battery's ability to absorb it.

Also, if you're in Canada (based on the links), you're not going to get the full power output any panel is rated for, because there is less sunlight there (you can look up "insolation" tables for various latitudes to get an idea).



I don't know anything about TEG systems, so can't answer that one, but if you're always generating waste heat, you could use the system all the time, which is a plus.


There's no perfect solution to offgrid travel charging, unfortunately. Dependign on the stuff you have, it could take a few hours to a few days to get a full charge on your battery.





If anyone can help me out with the timeframe of battery charging from empty to full , for all of the products above would be great and would set me to the next steps of the project ,
I'm afraid I don't have the math to do what your'e asking, but you might look up some of the various charge-whle-travelling, and solar charging, etc,., threads. There's quite a few, and some of them go into this in some detail.


But basically, it all comes down to:

--how much power do you get out of the wind/water/solar/teg unit, at the output of the charge controller?

--how efficient is the DC-AC inverter you have to use to be able to run your bike charger from?

--how efficient is the bike charger?

--how many Watt-hour (Wh) is the bike battery?

Assuming you have numbers for all those things, you can do a rough calculation like this:''

say you have 100w out of the charge controller. Say the inverter is 75% efficient. Say the charger is 80% efficient. Say the bike battery is 1000wh.

100w * .75 = 75w
75w * .80 = 60w
1000wh / 60w = 17 hours.

But if it's solar, you don't get the full power all day, only at noon, and you don't get any charge when it's dark or the panels are in shadow.

So assuming a worst case of 4-5 hours of usable daylight, and average of 50w out of the panels, that is twice teh amount of hours, for 34 hours total, divided by say 4 hours is over 8 days to charge to full.

Now, you may get much better results than that, as I haven't got any actual numbers for the bits you want to do this with, under the conditions you want to do it under. You may get some realistic numbers out of the solar charging threads, especially Justin_LE's Suntrip thread, and Solexec's solar bike thread.


Something else to consider is that you'll need to keep the batteries warm, as they don't like to be charged while very cold. The closer to freezing the more you should derate the charge current. Below freezing you don't want to charge them, AFAIK.
 
Well, first, if you completely drain your batteries, their lifetime will be measured in months rather than years. Go no lower than 20% charge.

Next, you would have a 52 volt, 20 ah battery, that is 1040 watt hours. IF, you had a 200W solar panel, in the Arizona desert at high noon, with no clouds, it would take a minimum of just over 5 hours to output that amount of energy, if everything was perfect, which it will not be. Also, the charger is not 100% efficient, everything gets warm, power is wasted, and it does not stay at high noon all day long. There are clouds, fog, etc.

I would figure on 2 or more days to charge on a regular basis.

Windmills are even more problematic, if you have time to wait for the wind to blow, fine, but sometimes it just doesn't. Sometimes it is cloudy and overcast for days on end.
 
Well to put some positvity into the thread.... I recently did a trip with 120w of (2x60w) panels that you could have put on a bike trailer no problem at all. I was using a lifpo4 4s 30ah battery and charging via a sla solar regulator and with bms. I was able to charge at 5amps and so it was only 6hrs roughly to full charge.
 
I've bought 2 waterlillys, planning on getting a 200w solar suitcase (they all have SAE style connectors, I have the splitter as well) , the output of both waterlillys would be around 30w, plus the solar panel would give a boost to that , even on dull days (I'll fold up the panel and store it inside the camper on downpours or snowstorm's) ... I've also got a couple waterproof cable entry glands for the cables.

And now onto the thermoelectric generator. I haven't figured out a plan for this component yet , the 50w continuous power generator I was looking at are liquid cooled, so I'd have to figure out a way to set up the water pump it bolts onto the side of the stove.... there is a stove top air cooled I was looking at that pumps out 25w continuous power... it weighs about a pound more than the 50w...

I was also thinking about getting more into it and learning the modules myself and rigging up my own generator

Either way , with all those 4 methods of generation, I will always have a reliable source of electricity...

And for reference the woodstove is a medium size tent stove .

Now for the ebike itself, I'm planning on a cyclone 3000w mid drive. With a 72v battery (20ah +) should be enough juice to help with the camper pulling . The bicycle is a 7 speed , generic fatbike frame . I'll be upgrading parts accordingly. Already have some brakes.

I also have bought a bicycle hitch/coupler, good and strong that connects to the seatpost.





Edit: I currently re read amberwolfs comment and am in the process of figuring it out further . Updates soon
 
Ok , to overcome the whole inversion and so I can directly get juice from the controller for a 72v battery, would this (or an alike) charge controller do justice ? Looks like in the description it's good for all kinds of battery . And there's an electric scooter in the pictures .

https://www.amazon.ca/dp/B073PR56R9/ref=cm_sw_r_cp_apa_i_wN3nEb8K1M8RQ

Is there a way to get the SAE connectors to be able to hook up to that controller? What kind of connectors will I need...
 
Probably at the reasonable end of cheap Chinese crap.

Check out Genasun, they might go higher than 48Vnom.

Have you ditched wind power yet.

You should be thinking like a long-trail backpacker, every 1/4lb is precious.

Wood stove LOL. Plywood? want space age materials. . .

Plug into shore power sometimes.
 
john61ct said:
Probably at the reasonable end of cheap Chinese crap.

Check out Genasun, they might go higher than 48Vnom.

Have you ditched wind power yet.

You should be thinking like a long-trail backpacker, every 1/4lb is precious.

Wood stove LOL. Plywood? want space age materials. . .

Plug into shore power sometimes.

I've since thought of a couple layers fibreglass over panel board. ALSO I've further figured it out. As well the waterlilly wind/water turbine are only a couple pounds.... Yes a woodstove, with a pipe oven and water tank. I'm not gonna be pulling it all over the place. Think pull it here for a week and pull it over there the next. Go about my daily diligence and come back to charge up etc....

And like I said I have a good idea on the weight/ pull ratio. People pull their kids in trailer's all the time , without electric assist.... That's also the reason I'm opting for a high tourqe motor... I've built a bicycle camper with a plywood base, using tarps and wood for the frame last summer. I kid you not I had no prob pulling it. I ALSO now have upgraded hitch and coupler made for projects like this. Check YouTube for bicycle camper's. The woodstove is critical in temp's below minus ten celcius. I've put a lot of thought and effort into this. And im gonna pimp this thing out to be the best it can. I've since ditched the wind turbine idea, now it's down to solar and thermoelectric besides my waterlillys. I just have to save up for the rest of the supplies now.. I hope to get started on this before summer.

And no ... That defeats the purpose... There's gonna be no shore power where I plan to take this thing.
 
Mhatayas said:
I've since thought of a couple layers fibreglass over panel board
That is **so** much heavier than you need.

Check out the Foamie sub over at TNTTT.com

> Yes a woodstove, with a pipe oven and water tank.

Just not practical IMO


> the waterlilly wind/water turbine are only a couple pounds

Sure, but the tower you need to raise when you happen to camp out in the middle of a windy plain, top of a mountain or cliff. . .

> I've since ditched the wind turbine idea

OK that's sensible

> There's gonna be no shore power where I plan to take this thing.

Well wherever that is, better be flat, and plan on being able to pedal your way out. . .

> now it's down to solar and thermoelectric besides my waterlillys

What are the waterlillys for then?

What thermoelectric you talking about, like trying to extract energy from hot springs?

You aren't thinking of using these non-mains sources for recharging batteries used to propel your rig around are you?

More like recharging a phone, running a little fan and a few LEDs maybe.

> That defeats the purpose

Just what is your purpose then? Just a "pro green" demonstration?

Practicality to be ignored?

 
The Waterlilly is clearly just a gimmick but an intriguing gimmick. 15W is useless IMO. With some DIY effort and a good BC river you could probably build your own water wheel generator in the 1kw range that's pretty light and compact. Now THAT's power. With your larger battery size of 1.4kwh (72v/20Ah) that would charge it in 1.4 hours, reliably, every day, and at night.
 
If only rivers were portable.

Seriously, even with a truck or van pulling the trailer, wind power wojld not be practical.

Nor hydro.

Solar in very hot and sunny conditions, anything under 1000W will only give a couple hours' propulsion per day at slow speeds.

Fossil fuel is the only practical energy source for recharging a small mobile living space while away from grid mains.

And burning wood is horrible for both the sake of the environment and any humans breathing nearby, proven to cause cancer.

I know idealistic noobs will call me "negative", but I lived completely off grid for decades and am as greenie as they come (spiking trees to fight logging long before the first Earth Day).

But physics is a hard mistress, learn enough so that your strategies are realistic.

If you're OK only traveling a few miles per sunny day, then sitting at a campsite when it's cloudy for days, well that's another story, more power to ya!
 
john61ct said:
If only rivers were portable.
One great thing about rivers is that roads, trails, and pathways are built alongside them for miles and miles and miles. If you plan your route a river is a tremendous source of energy.
 
I've since went on with the build, have a small woodstove, projector screen, strong legs to hold the camper up , eye bolts as tie down points for ground anchors (gets up to 200km/h wind)

I tested the anchor's out yesterday in a wind/rainstorm , they work great, when my door is pointed downwind I can leave it open and cook from the outside etc....

As it goes for woodstove, it has a thermal plate , which helps me cook /boil water , usually leave my door open and erect a folding chair to cook from the outside , the stove is by the camper door

As it goes for powering the thing, I have 2x 10w solar panels zip tied to the roof , they trickle charge a 25000mah power bank for usb devices , also have 2x 60w folding panels , I usually store them in the bikes box on the front rack , I use those paired with a charge controller to charge a 52v battery, would take a day or two for full charge , the hitch point for towing the trailer is on the end of the bikes rear rack , was thinking about a 100w or so panel to permanently mount on the top , as for now I have string running across the camper like ribs that I use as tie down points for my folding panels/ tarp as awning


As it goes for rivers etc , I have a folding coroplast kayak I strap and carry around underneath my camper. There is plenty of water around , no worries there
I can tow it up a steep hill , by bike or by hand
 
Here is a picture of the setup so far , the camper is 4x8long 4high (from the floor up)

Note that the string to tie down the panels is not on the camper yet
 

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Mhatayas said:
As it goes for powering the thing, I have 2x 10w solar panels zip tied to the roof
Did you mean to say 100W? 100W flexible panels are now readily available and work well.
was thinking about a 100w or so panel to permanently mount on the top
Yes, much better idea.
 
Really cool little home, Mhatayas! Thanks for sharing and glad to see it's working for you! I have been thinking of ideas for river water generators, maybe you can build one out of your bike and hub motor? Bike wheel with paddles on it using the hub motor as a generator that you can quickly swap out and back onto your bike after charging? Just an idea.
 
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