Solar camping trailer to recharge ebike while overlanding

I think i'm still a fan of the 'coffin' camper/ hard shell box. After several weeks in grizz country knowing the odds of waking up each day would make for a better sleep :) Met a lot of 'perpetual travelers' in the US, so many enormous rigs.. seems to me the lifestyle would be ideal given your variety of latitudes/terrain/access to other countries (even) by road.
 
looks very interesting dan. curious to see what what you put on the flatbed. ...also would love to have desert around me. everywhere mad chinese screaming, honking, fireworks 24/7... sounds like you are living my dream there.. all the best with the recovery!

the 10 year old sprinter was only about various electronics issues, rust (from inside and outside) and failing automatic transmission. i would love to have an old and simple vehicle again. that is made to last. new cars are not engineered for more than about 8 years of life. an hanomag would be great. will be looking into a russian GAZ when back in europe. there at least i have a chance to fix issues that arrise.

wondering how to heat my coffin camper.. put a hot rock from the campfire in it..?! :D
 
I was joking with my wife, "got my coffin built honey". I was too tired to do it when I thought I was dying soon.Coffin camper.jpgCamper height.jpg


It's about 16" tall, 25" wide. 8 feet long. The height when hitched up is about 26". The width is just barely enough to fit a camping cot I have, the height enough to fit the mattress for the cot in, on top of the cot. Also tall enough for an Ice chest, or a 5 gallon bucket.

It weighs about 50 pounds, just the box is about 20.

Too short to sleep in of course, but you could hunker down in there if weather got so bad a tent did not cut it. To make it a sleeper, you'd want to make it boot shaped, or wedge shaped. You simply cannot be comfy in anything less than a meter tall. You have to be able to sit up fully.

As for griz country,, I simply cannot imagine a bike trailer light enough to tow slowing down a bear any longer than a tent would. Bears learn how to peel cars, open supposedly bear proof food containers, etc. Carry the spray. or a 45.

So how did it tow? Not bad, I did the first test with 200 pounds of gravel in 4 buckets. Not a long trip like that, about 2 miles. the wheels did bend in as Amberwolf was sure they would. Because of the extreme 8' length, about 6' from hitch to the wheels, it tows very nice. Even with 200 pound load, I could ride no hands. After I got home with the gravel, I lightened up to the load I expect to carry, about 100 pounds. This means 150 pounds in total load. This towed much nicer, less force needed when steering inputs are done, and it easily corners at speed. Speed meaning 13 mph, the max this particular bike can go on flat ground with the trailer loaded. 18 mph top speed for the bike alone,, it's a tractor build, not a speed bike.

Fixing the bent wheels was easy,, I just slapped this wheel carriage together, using an old real estate sign and the two forks. The sign was not welded so great, so I easily bent it back, and added the weld it needed. Did not test it yet after the fix, but I expect it will be fine. Some improvements will be needed for the hitch, but I really don't want to go with a real car hitch, because of the weight. For now, a grade 8 bolt will do.

I get about 32 wh/mi, riding in some pretty decent wind, about 10 mph with 15mph gusts. Nasty day for the test. This would give me about 45 mile range with the trailer in tow, (35 ah of 48v battery)

I'm thinking a very comfy camp can be carried for about 70 pounds, leaving 30 pounds free for a small generator, or better still solar panels on top.

VERY likely, I'll cut the size of the box,, making it shorter, and leaving some flat bed on the back for a generator to ride there. But I was quite amazed how little the box felt like it created wind drag. Its nose is in the burble of the bike, and it's length is pretty slick. Does better than I expected.
 
very nice - perfect to carry some solar panels along.

8 feet is too short to sleep in? :shock:

thinking of a similar box - just a little wider. the top cover extending over the side walls, so it can be lifted a little for camping mode and still provide protection from the elements. hinged at one end you get the an frame. :)
 
Should tow really well, long and low like that.

You could make a pop-top style Joe, pop up to 1m+ with shelter awnings, inbuilt kitchen, flat screen etc :)

(I had an electric fence for bears running through a 12v step down, ditched it with the solar panels early in my tour) Both great ideas, not properly thought out by me)
 
Should tow really well, long and low like that.

You could make a pop-top style Joe, pop up to 1m+ with shelter awnings, inbuilt kitchen, flat screen etc :)

(I had an electric fence for bears running through a 12v step down, ditched it with the solar panels early in my tour. Both good ideas, not properly thought out)
 
Coroplast is super cheap and super light-weight. I think some of the coroplast trailers I have seen on youtube look cool.
[youtube]ZiejAhol4Ps[/youtube]

I think that the competitive long distance solar bicycle website: SunTrip is a good place to soak up some info about solar
http://thesuntrip.com/a-solar-adventure/


When I did it I very much enjoyed having the solar panel as a sun/rain shield.
Here's my solar rig
https://endless-sphere.com/forums/viewtopic.php?f=3&t=80117
and my 251 mile trip
https://endless-sphere.com/forums/viewtopic.php?f=3&t=80340
file.php

file.php
 
seen these vids already. love the upcycling idea :!:

i had some ideas to extend the panels from the trailer to provide sun and rain protection..
but on a normal bicycle it will be too high and far from the trailer's CG. riding in windy conditions and uneven terrain will be too difficult. but perfect for a two-wheel trailer and tricycle on long streches of good roads i guess.

any experiences with tilting the panels when riding? is it worth it? better charge or ride mid-day?
 
I meant too short in height to sleep comfy in, with the top closed. It's about 17" inside. 8' plenty of length. I'd planned on making the box 6'6" or so, but the ladder was 8' and so it went. A tent, covered wagon style, would be easy to do. PVC pipe hoops and a good tarp.

Mostly,, I just wanted to test what wind drag would be, on coffin size box towed behind the bike. Not too bad loaded to 100 pounds of cargo, but go to 200 pounds, and just going 13 mph zooms power use to over 40 wh/mi. I needed to know what going to that heavy would do to my power use. Looks like I need to keep it close to 100 pounds max, including solar, or generator.

What will fit on top, is only about 200w of panels. So figure 150 w? for 6 hours. More in summer maybe with longer days, but not every day of the year. so 900 wh or so? You could progress perhaps 20-25 miles a day on that if loaded to 200 pounds. That means you still find yourself sitting at the quickie mart for hours each day, grabbing a charge.

Ditch the camping idea though, and 150w added to your 100w of pedaling will give you just about infinite range, till the sun stops. The catch 22 here, is adding 150-250 pounds of weight to your rig. It will shorten your range a lot to carry enough to camp really comfy. I'm too old to squat, sleep on a half inch pad, etc.

I just keep coming back to the idea of carry a generator. Not the 90 decibel harbor freight one, but a quieter, lighter generac. 800w continuous for 30 pounds, and quieter. Locate it 9 feet behind you, maybe not so bad to hear it run all day. I have 500w worth of chargers, so range would become more or less infinite, and routes with no plugs for a hundred miles become possible.

In any case,, I'm still chained to the internet for at least 3 more years. So nothing planned beyond a weekend trip. My vacation time is always pre committed to a week of ballooning in Oct. My current battery size only goes to a 40 mile round trip. Big woo.

The trailer easily carries 150-200 pounds, but the wheel truck should have been built from heavier, harder to bend steel, or built more like a web truss. The actual welds connecting the forks, and the forks themselves are holding up fine with 200 pounds of load. I'm sure there will be eventual wheel problems, on a long tour, I'd carry an entire spare wheel. Or build a good set of wheels that aren't kid toy stuff. Like larger trailers for trucks, 4 wheels is also possible.
 
In regards to Suntrip 2015 (the long-distance solar bike challenge):
Everyone packed a fair amount of battery. 800-1100 watt hours of battery pretty much across the board. I didn't see any packs above 1100 watt hours so I presume ruling must have limited that or all the riders favored lighter weight.

Here's a list of the other panel sizes (from what I could gather) just to give you some ideas.
Raf Hulle: 280watt
Tom Papay: 220 watts in use 440 watts parked and unfolded
Dirk Huyghe: 250 watt
Oliver Reginensi: 300 watt
Antonio De Chiara: 500 watts while in use 700 watts parked and unfolded
Denis Bertet: 240 watt
Arno Liegeon: 250 watt
Paul Bermejo: 200 watt
Henri: 200 watt
Pauline de la Marnierre: 300 while riding 600watts deployed.
Francois Mendez: 300 watts
Andreas Nandita: 260 in use 390 watts parked and unfolded

Nearly all rider favored fixed position solar panels over aimable panels. With regard to the tiltable panels used most were tiltable only with the bike parked. Personally with my setup the amp-input was nearly the same even if the panels were shoddily pointed at the sun. 20 degrees off and I was still getting pretty good amp flow. The greatest benefit to tilting was very early morning and very late afternoon where I could lay my panels like this to get best charge:
file.php


If you are doing cross-country just for funsies and not a competitive hardcore grind, you probably aren't going to want to spend a whole lot of time in the saddle every day. I would consider 8 hours of riding a day to be pretty "hardcore", however I may just be a bit of a pansy.
In the early morning my PWM controller was showing an amperage yield of about 4-5 amps (panels pointed straight up) which I preferred to exceed draining the battery slightly to favor a higher speed of about 15mph. I would hit a magical time from about 10:30 to 2:30 where I was getting 8-10 amps (~48 volts ~400-480 watts) out of my 450 watt panels (probably overkill large) and a 15mph average would also slowly get the battery back to full charge. I tended to not want to get fully charged because I wanted to stop and eat lunch and it seemed wasteful to just have the trike sitting there not charging when I could have used that energy for higher speed instead. This would lead me to flirt with 20mph which was draining on the battery at all hours of the day but finagled properly I could make it so I could stop for lunch and get nearly full charged again and run the battery down pretty low around the time that I wanted to stop and set up camp.
 
A generator will be my last resort if I see things are not working out.. But then this makes the whole ebiking ridiculous. It would be much cheaper and more efficient to ride a standard moped in the first place... and with an ICE moped I would never have had conveived the idea of a trip with a trailer.. :mrgreen:

@ parajared
thanks for sharing. I can't wait to get started. My plan is also to visit Mongolia like the German couple from the link.
with off-roading + panels I meant to use them as sun shields. they would be sitting too high over a normal bike and if attached to the trailer the sunshield would come down on my head when the trailer goes over a bump. :roll:
 
The Mongolia trip set up looks pretty good, except I wonder what happens when the bike gets dumped sideways/falls over? The edges of the modules look pretty vulnerable. The comment "they supplied all our electrical power for the trip" I don't doubt, but looking at the array size, and taking a good guess at the amount of power they were consuming, there must have been a LOT of pedal assist going on too. A very impressive trip, wow. Also,it looks like it would be fairly simple to unhook the trailer and do a little manual tracking when parked. Minimum aero drag with that setup too.

I love the picture of what looks like a monk on an ebike!

SOMEONE....needs to come up with a super light gen set, using the little Honda 4 stroke motor like I have on my weedeater. A direct coupled (no gearing up or down mechanical losses) specially wound, for the motors torque curve and the desired out put, alternator (generator?) that could charge the battery directly. 3 to 500 watts would be nice, for an all up weight of 10 lbs or so? Carrying a siphon hose would enable buying more along the way. Seriously... when I was flying XC in ultralight aircraft, many times I'd run across a situation where I could buy some gas from someone in a car or whatever, but unless you had a way to get it out of their tank, it was no deal. Paying twice the regular gas price was my usual offer, and 99% of the time they'd refuse and be happy to get paid whatever it cost them. I truly learned the value of a single gallon of good old, and often besmirched, gasoline, when off grid for 28 years. It's really magical stuff. Yeah we all want to be 100% solar, but damn, just a gallon every now and then, NOT all the time, sure pencils out to be a godsend in times of cloudy weather and heavy power consumption. Whether on a bike or in a home! I guarantee you a good gen set is a crucial component, but one they don't like to talk about much, of every 100% off grid homestead, it's a dirty fact of off grid life, that and using a lot of propane. With cheaper prices for PV now, if off grid again, I'd have a much bigger array then before, and MAYBE never need a genset, but on a bike it isn't the expense, it's the weight and space they take up. Heresy I know, to mention all this on a thread devoted to solar transport, and maybe it's better to just deal with the current inherent limitations with PV power on a bike by not being in a hurry at all, and pedaling, a lot.
 
yeah, buddhist monks are curious about EVs too..

it's 42Wp per bike. i cannot believe this was significant support. pictures show lots of clouds and the texts mention rainy days a few times..
 
I guess that's what I'm getting at.....it was one heck of a impressive physical venture by some really in shape people, but hardly "solar powered", assisted, sure. And, it'd be a lot less interesting story if they had had a 10 lb generator instead of a solar array! It's totally weird to me that I find myself as a critic of anything solar, since I have used it on a daily basis more and longer then most here, but what we really need is less weight and double the efficiency of the current best modules, imagine if a present day light weight 100 watt panel put out 250 watts, and weighed less?! It'll happen eventually.

BTW, while typing this, my light, computer, and 750 watt electric panel heater along side my chair, is all being run off a combo of stored hydro/wind/PV power that was stored in the grid until now. Actually, since the wind turbine is putting out 2400 watts, I'm using 870 watts directly and the remaining 1530 watts is going into the grid and turning my meter backwards, fun stuff!

I have heard that small wind systems are a large part of how remote parts (all of it) of Mongolia get a lot of their power, the open plains get real windy, often, not sure about their percent of sunny days.
 
craneplaneguy said:
... imagine if a present day light weight 100 watt panel put out 250 watts, and weighed less?! It'll happen eventually...
Click to expand...

sadly there is now way to do it with cheap c-Si panels:

https://en.wikipedia.org/wiki/Shockley%E2%80%93Queisser_limit

Other types you may not be able to afford. Even race solar mobiles worth several million US$ and space applications mostly use lower efficiency c-Si cells now...
 
As Parajed showed,, you can carry more than 100w of panel. The trike of course makes it easier. But a wider trailer than I built would carry 400w.

That would weigh 20 pounds for 400w of panel. But a bit wide for the edge of a road with cars going 70 mph whizzing past you. Likely not a problem in Mongolia though.

My personal problem is I'll never pedal like that Muller gal. The ratio of wh/mi to 200w of panel gets a lot better if you motel it, rather than have to carry it all. If I could afford to motel it, I'd just ride at 25wh/mi, and my battery would take me 80-100 miles a charge.
 
That's pretty light for that many watts. Right now, I have over 20 REC (brand) 280 watt panels in my shop, stock for my little local solar biz, water pumping systems and ranchers being my biggest customers for them. They are a residential type, as such, built to last, with heavy aluminum frames. 40" by 65" and a bit over 40 lbs. Packing two of them around would provide some decent power, but not real practical at 80+lbs! That extra weight could be partially offset by their heavier structure being used as part of a trailer frame (just a thought) but still, way too heavy. They are pretty cheap though, I bought a quantity of them for a bit less then $200.00 each, including freight. I remember buying 100 watt panels for $500.00, and was happy to get them at that price, years ago, so to me it seems like they are giving these away!
 
i'm afraid i'll have to ride a lot against the prevailing winds in northern china and mongolia..
but the sun should be strong in the gobi desert :)

found 'flexible' panels with back contacts at 1m x 0.5m with 100Wp at around 70USD each. thinking 4 or 5 of these. one is 2kg.
..maybe glue them on an aluminium panel to increase chances that they survive..
 
Good price for those panels,, Of course, cost more shipped to here. Stick em to some coroplast, light, stiff, won't degrade in the rain. Give them some extra at the edge, like 50 mm, so in a tip over, the coroplast bends and gets beat up, not the panel. The panels I looked at were made to Velcro mount.

I was quite amazed how light they are, when Parajed started his project and I first heard of them. I was also thinking a 150w panel was always about 100 pounds.
 
joe81 said:
i'm afraid i'll have to ride a lot against the prevailing winds in northern china and mongolia..
but the sun should be strong in the gobi desert :)

found 'flexible' panels with back contacts at 1m x 0.5m with 100Wp at around 70USD each. thinking 4 or 5 of these. one is 2kg.
..maybe glue them on an aluminium panel to increase chances that they survive..
Click to expand...

With horizontal panels near the ground, wind is NOT a problem. The wind flow near the ground is parallel to the ground and the panels. I have ridden with 200W of flexible panels on my Terratrike Cruiser in 45mph winds without any problem at all.

Gluing or otherwise mounting the "flexible" panels to a relatively stiff substrate is a good idea. I was not careful enough with one of my 100W Renogy flexible panels and I allowed some "local" stress at one of the attachment points. Last week that panel CAUGHT FIRE and burned a small area which I assume was shorted out by the local bending over the years. I'll try to cut that area out and remove any remaining short and maybe the panel will still work. Fortunately, for me they are just fun tech toys and not critical to anything I am doing. The other 100W panel is happily keeping my golf cart fully charged but I don't drive the golf cart all that much during the week so it has plenty of time to charge.
 
Being as flexible as they are, and light, there is probably no way to mount them other then onto a back lying solid surface of some sort. The thing is, heat build up is the #1 reducer of power in any PV panel. That's why two exact arrays of the same size, one roof mounted and one pole mounted will produce different results. the roof top one, even though the modules are spaced out from the roof a few inches, will run hotter, while the pole mount array will produce substantially more power. I would think in this case, where you'd need every single watt, an effort to provide backside cooling would be worth it. Some kind of perforated surface perhaps, solid enough to provided the needed structure, while still letting a little air get back there. I cringe when I see PV on RV's, caulked down tight all along the edges, so no air flow behind. I think I've seen the Corplast type material with grooves in it? That would be preferable then a smooth and flat surface.
 
Just embarking on my Solar PV Ebike Trailer project.

So far I have collected the following:

280W Itek Panel: http://www.itekenergy.com/wp-content/uploads/sites/72/2016/09/HE-Mod_Specsheet_WA_V09-01-16.pdf

1200W DC-DC COnverter. up to 60V Input & UP to 80V Output: http://www.ebay.com/itm/171914356048?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Power Meters to track input & output voltage, current, wattage & energy: https://www.amazon.com/gp/product/B013PKYILS/ref=od_aui_detailpages00?ie=UTF8&psc=1

Assumption is that the DC-DC converter will adequately act as my charge controller for a 16S Lithium battery (67.2V Charge voltage) If I get really bad conversion efficiency, I may add an MPPT controller into the circuit before the DC-DC converter to stabilize the input voltage.
 
You must log in or register to reply here.
Back
Top