KC8QVO

Mark - If you are referring to a mini hydro generator that spins with water flowing through it - that sounds like a neat idea, however it may be rather limited.

Hydro in and of itself isn't a bad idea, however if you can combine a generator to use other forms of powering that would be ideal. For example - use a larger paddle wheel of some kind to turn a generator that can also be converted to run off of wind blades. If you aren't camped next to an appropriate stream for the hydro generator to run you would have the option of wind blades to power it.

KC8QVO

For what it is worth, the solar panels I have and take with me on my trips (backpacking and cycing) are made by Power Film. Below is a link to the larger panels I have. They are all small and flexible. I join several "panels" together in parallel to multiply their capacity. If you watched my ride video (the link is in the thread on my 52 mile ride in Ohio here in the Touring forum) I showed both panels and the charge current of each plus together (1.27 amps in to a 12v class LiPo4 battery (13.5v or so)).

If you think about wattage vs weight and complexity solar is the most "efficient" form of gathering power. By running all accessories from a 12 volt source you can "standardize" easier as all modern electronics can run off of 12v systems for use in vehicles (tablets, cell phones, battery chargers, music players, kindles, etc).

The obvious drawback to solar is it only works well when it is sunny out - that isn't all the time in most places.

If you look at hub dynamos - they are 6v systems for one, however the bigger issue is the low wattage. They only put out 4-8 watts, generally. If you use a 12v system then you need to step up the voltage (power loss) to get to a usable voltage from which to charge. That leaves you with even less usable power. The smaller of the two solar panels I have was putting out about 300mA of charge current - at over 13 volts - on my ride in the video So lets use 300mA an 13v as an illustration - that is a hair under 4 watts - at 13v. The total with the big panel also was 1.27 amps, or a bit over 16.5 watts. Again - thats with a 12v battery, not just charging a cell phone or a 6v system. Much more power possibilities there.

The following "panels" can be paralleled:
https://www.powerfilmsolar.com/custo...nels/mpt15-150

So figure each one is 100mA. If you put 20 of them together that is 2 amps If you had a coroplast bike camper and lined the roof with 60 of those panels that is the potential for approaching 6 amps (curved roof = not direct lighting on panels opposite of the sun, so not possible to get to that unless the panels are all able to be aimed at the sun) . I doubt you are going to get that type of power from any other portable means.

Mark Hoaglund

From my simple point of view the turbine on cloudy, rainy days and dark nights would be a useful electrical backup device sourced from water, wind and hand cranking. I don't always have to be a nomadic tourist but I do like useful electronic creature features such as a solar free energy generator too.

Mark Hoaglund

KC8QVO thank you for sharing your thoughts. I'm thinking about your solar interests & considering a solar RV cycle trailer design using those ideas:

Solar Radiation Data Manual for Flat-Plate and Concentrating Collectors https://rredc.nrel.gov/solar/pubs/redbook/

Solar Radiation on a Tilted Surface https://www.pveducation.org/pvcdrom/...tilted-surface

https://www.amazon.com/PowerFilm-MPT.../dp/B002MFP9SO

KC8QVO

Mark Hoaglund That Amazon link is one of the panels, however that price seems very high to me. There is a convention in Ohio called the Dayton Hamvention that I have been to every year for a long time and that is where I got mine. They were selling them in packs of 10 or 15 pieces and I don't remember them being all that expensive - maybe $50-60. Over 2 years (2 conventions) I got 3 packs - 2 of the 50mA panels and a pack of the bigger ones. I know I have some of the small ones around, a whole pack at least.

I have been using 12v class batteries to run portable electronics for years. On my first backpacking trip in college I had a 7Ah SLA battery and a Yaesu FT-857D ham rig on the trip (3 days, around 20 miles in the appalachians). I used various size batteries including 12Ah SLA and then a 9Ah SLA (still have the 9). The SLA's just are so heavy. That is what is really nice about the Lithium Iron Phosphate (LiPo4) batteries - for the same nominal capacity they are nearly half the weight. However, you actually get more power usage out of them as the voltage doesn't sag like it does with any lead variant.

Having the storage capacity and set up to run electronics from 12v is one thing, but how you recharge is pretty important. Having internal batteries in a phone or tablet then the ability to charge those alone doesn't go very far. Maybe for some people it will - and that may be all they are concerned with. However, I have things that run off of 12v also and since I can charge my phone and tablet off of 12v as well it just makes perfect sense to have everything set up for the same 12v power. So again - how to charge is the question. You need real power (still small, yes) - not a solar powered battery booster pack for a cell phone where you plug in a USB cable to charge your phone, or one of those BioLite stoves that converts heat to USB power. That may charge your phone, yes, but you aren't going to charge a 12v battery from it.

With that same idea in mind - that goes back to my point about the solar panels. I can get power out of them, even on cloudy days (not a whole lot of current but at least some). Anything that is geared towards charging a cell phone is never going to give any real power.

The link that you posted about the angle of a surface in relation to the incident angle of the sun light hitting it changing the amount of energy (decreasing it) that is seen at the surface is the same theory of what I mentioned about panels lining a curved roof on a coroplast camper. When I set my panels up when I stop I try to aim them in to the light as best I can. On my ride in my video I had the panels spread out on the ground - sloping down an embankment towards a lake. That was still not very direct in to the angle of the sun, but it was better than flat ground. That netted 1.27 amps of charge at 13.2v or so. That is some respectable power - close to 17 watts.

Mark Hoaglund

KC8QVO I'm a novice and want to add to my
$130 Voltaic 1.8 lb. 6W solar panel with 44Wh battery & considering a
$330 Jackery 7.3 lb. 60W solar panel with 167Wh battery
what's your thoughts, ideas, suggestions?
https://www.amazon.com/Jackery-Explo.../dp/B07FYJVFNK
https://www.amazon.com/Jackery-Solar.../dp/B07PGS2WN8

Mark Hoaglund

Its so cute tempted to just order the Jackery Explorer 160 and solar panel at a later date. It sure would be nice & small in my cargo trailer and/or mounted on top while touring. Now I'm wondering about watts per assisted ebike mile on the rail trails.

KC8QVO

I had never heard of that before so I googled it. Interesting concept. I've seen power packs like those before, in fact we have one. It uses an SLA battery and is for boosting dead car batteries or powering accessories (has jumper cable alligator clips and a 12v accessory port). I don't recall what the size battery is in it, but it isn't something I would consider "portable" in the sense of carrying it along on the bike. The Jackerys look like they may work though.

I am digging in to the specs and the weight doesn't seem right. It shows it weighs 3.84lbs with an 11.6Ah battery capacity, Lithium Ion. Keep in mind the case and all the electronics (100w AC inverter, connectors, etc) all add weight also and, my understanding, is that is all included in the 3.84lbs.

The battery I use is a Bioenno 12Ah LiPo4, model BLF-1212AS. It weighs 3.6lbs. So about the same capacity as the "battery" inside the Explorer 160, yet only .24lbs less only in a plastic enclosure with no other electronics (bare battery and protection circuitry, no inverter, charger circuit, connectors, etc).

Maybe the lithium ion batteries are that much lighter than lithium iron phosphate.

In any event, lithium technology is the way to go with batteries.

Their solar panels look interesting. The 60w version would be a nice unit to pair with any battery in that class - maybe even bigger capacities.

My solar set up is only about 17 watts and will work to offset my use pretty well if the sun is shining. 60 watts would be really nice for some quicker charging.

Fun stuff!

Mark Hoaglund

An estimate of myself on level, calm, asphalt roads :

Cycling Wattage Calculator – Omni
https://www.omnicalculator.com/sports/cycling-wattage
Love the contents, explanations and formulas with simple, basic inputs for metric & US.
210 lbs myself for example
90 lbs bike, gear, eMotor, batteries, food & liquids

Watts per hour divide by miles per hour = Watts per mile
19 W per hour / 05 mph = 3.8 W per mile
55 W per hour / 10 mph = 5.5 W per mile
125 W per hour / 15 mph = 8.3 W per mile
250 W per hour / 20 mph = 12.5 W per mile

I choose a battery for my future eBike with
48 volts x 11.6 amp hours = 557 watt hours
At 10 mph 557 Wh battery divide by 5.5 Wh per mile = 101 miles per charge.
Or 6,100 eMPG and human power assist would increase the mileage noticeably.

Mark Hoaglund

Thank you Steve and here's a couple links to look over as I await your approval:
https://www.jackery.com/products/exp...-power-station
https://www.jackery.com/products/sol...0w-solar-panel

Mark Hoaglund

What IF a free-energy carbon-neutral tax-free alternative to the high cost and burden of the fossil fuel industrial transport energy monopoly were possible? One step at a time... with the Jackery free energy solar generator, for example, going 10 mph using 55 Wh of the 60 Wh solar panel on level, calm, asphalt roads traveling 50 miles per day or 60+ miles with human assist.

NOTE: The 167 Wh battery can be recharged in 5 hours from AC, DC & 60 Wh solar panel. All very ideal.

Happy Feet

There is. It's called a bicycle.

FWIW, I sometimes use a simple folding solar panel and powerbank. Charges my phone, light and IPOD without need to resort to ebike status.

stardognine

I need to look into this much better. I carry a couple decent batteries already, but charging gets to be an issue, at times. Those solar panels look pretty light to carry. Are they? 🤔

Mark Hoaglund

Oldtimer afflictions require some ebike assistance nowadays so ordered the Jackery Explorer 160 for $140 plus tax. Its so cute, compact & YT unboxing accessories caught my eye. The Explorer 240 would've been nice too.

KC8QVO

Mark - the wattage calculator is for how much power it takes for you to move the bike + gear. That isn't the electrical wattage that you can harness.

There was a study done by someone in the past couple years that measured, with a fair amount of accuracy (nicely laid out testing), the efficiency of hub dynamos and how much power they consumed from a moving bicycle. It was done on test stands, so no bike in motion, but the point was to calculate input mechanical power (overcoming losses) vs electrical power output from the dynamo. I would think this study would be of some interest.

My point - the electrical power that you are able to harness (however you do so - if it is a mechanical means) is going to be much less than the input power that you are exerting to move the bike. You have the power consumed by just moving the bike then you have to add on the resistance caused by your power generation method. That only adds to the power required to move the bike, not take away.

So the real power that you are able to harness is going to be impacted two-fold - the mechanical power in to move the device then again for the conversion of the mechanical energy to electrical energy.

Just food for thought. Good stuff though.

KC8QVO

A 60 watt panel would be a blessing on a ride. Both of mine combined are under 20 watts depending on their orientation to the sun.

I would say I use more power than most people ever will when on trips because of the ham radio stuff. Even when I don't use the radios I still have a bike computer (Edge 1000), tablet, and phone to keep going.

With the bike computer, phone, and tablet alone I can get a full day and night's worth of keeping stuff charged and going on a 12Ah LiPo4 battery. With the ability to recharge - the trick is getting the amp-hours/watt-hours back in to the battery. That is where charge current really comes in to play and the only way you can get charge current up, in the way of solar power here, is to have sizable panels - which the 60 watt panel mentioned here would be a good option I would think.

Figure if I draw 1.5 amps at 13.2v for 3 hours that is 4.5 amp-hours. So with, say, 1.25 amps of charge current - to resupply that 4.5Ah used (with no more draw) I would have to charge for 3.6 hours. If I am on a trip where I need t keep moving the charge time is time I am not able to move. So it is a give-and-take system.

That is where having the ability to run a solar panel while you ride is a good thing. As Happy Feet pointed out - you can lay out some panels across your gear on the back. I do this quite often with my small panel to scrape some photons as I ride. It doesn't keep up with the draw, but it most certainly slows it down until I can get to pushing some more current from the big panel. It all takes some tuning to how your system operates.

As an aside - any alternative energy system (solar, wind, hydro, what have you) is a balancing act. You have to have the storage capacity, and draw, to balance your generation capacity. The reverse is also true - you need to balance your draw to the amount of generation capacity you have.

So if you have a 12Ah battery and 3,000 watts of solar panels you don't have a very well designed system.

On the other side of the fence, if you have 17 watts of solar power and 500Ah of batteries you can't charge that bank very fast at all. You may be able to run a high power inverter off of that 500Ah bank and run your house for a couple hours, but at 17 watts able to go back in (when the sun is shining) you aren't going to make much headway on keeping up with the demand.

So the name of the game is to try to work with averages. It is always better to size up - both in battery capacity and charge capacity. With solar it is pretty easy to do away with excess power - use a charge controller of some type that will stop the current flowing in to the battery(ies) when full. Mechanical generators can be a bit more tricky, especially wind turbines - you don't want them to be "unloaded" so if the battery(ies) are full the general idea is to send the power to a giant resistor, or dummy load. Otherwise you end up with a free-spinning turbine that can over-speed. Some designs use mechanical brakes instead, but most home-brew turbines, especially, do not - they use the resistance of the power generation (or dummy load) to moderate the speed.

In any event, you don't want to have a huge gap between either storage capacity or generation ability. However, you have to know what type of average consumption you require to get the most to-the-point results.

Admittedly, I have not run the calculations on what I consume on a trip across the course of a day and night. I can measure current - both in and out (depending on which way I set the meter up), but it does not show average or accumulated consumption over time. That is something I intend to get - a meter that will record usage (and supply - again, depending on where the meter is installed - or maybe 2 - one for draw an one for supply). I can tell you I've been happy with my 12Ah LiPo4 battery, though - way more than even a 12Ah SLA.

Last comments for now - the amp-hour rating on a lead-varient battery (AGM, SLA, etc) needs to be taken carefully. Around 40% of that use is "safe". Even at that as you draw power from a lead battery you get a drop in voltage. The higher the current drawn (the C rating - C being equal to the Ah capacity - so for a 12Ah battery 1C = 12 amps) the lower the voltage that seemingly comes out of the battery.

With Lithium batteries you can draw up to 70%, or maybe higher, "safely". Additionally, if you look at the voltage curve - the Lithium batteries stay up on voltage much much longer then rapidly tank as they approach depletion. That is where that 70% rating comes in - you can over-draw lithium batteries and stopping the draw before the sharp voltage tank is a good idea to prolong life. Lithium batteries will also supply a lot higher C than a lead battery will as well. This won't be of any concern/use in the cycling world, but if you ran across someone on the side of the road with a dead car battery you could jump start them off your lithium battery I suppose hehe. In general, though, portable power uses are for recharging electronics (phones, tablets, bike computers, ipods, kindals, etc) or powering other accessories like maybe a fan or lights. You won't be carrying anything on a bike that will really "consume" power. Even my ham radios I've run off SLA batteries for years - switching to a Lithium doesn't net me any benefit with the higher C, just the lighter weight and hanging on to voltage longer are wonderful to have compared to SLA's and AGM's.

Mark Hoaglund

Perhaps I should have entitled my post:
Estimate of ebike touring power needs
which gives explanation & consideration to:
Component 1: gravity
Component 2: rolling resistance
Component 3: aerodynamic drag
Component 4: cycling power losses

KC8QVO

Mark - from the section on "What is the cycling wattage?" on that website:

So, again, that refers to the mechanical power your legs are putting out to get the bike moving.

You will need to figure out how much extra drag is caused by power generation. Once you have this factor then you can combine it with the data from the calculator online. However, you can not simply go off the data on the online calculator solely as it is not taking in to account the additional drag from the power generation.

I looked for the article on the study I alluded to earlier. I can't find it right off hand. I will keep digging and see if I can come across it.

For anyone else reading - the study I am referring to was a group that set up a test measuring resistance (mechanical) of various hub dynamos. It looked to have been done in a garage with some fabrication machines and wood workbenches/tables. The theory of the tests and fixture designs were well explained and documented. If that rings a bell and you know where it might be add the link here.

Mark Hoaglund

Thank you Steve. I see some ebike calculators for further ideas:
https://www.google.com/search?q=ebike+calculator

Something that puzzles me is the comparison of:
20-25 percent human efficiency
80-97 percent electric motor efficiency
and how that pans out in converting kcal & Wh consumption.

KC8QVO

Mark - getting in to caloric intake and burn is well outside of my wheelhouse, unfortunately. I am sure others can chime in that may have a better understanding of that.

Speaking very generally, however - there are always losses in power conversions. Power conversions meaning transferring energy from one medium to another. For example - mechanical power transfer to electrical energy - you have physical resistive losses that are soaked up as heat (friction, etc), then there isn't a 100% transfer between the mechanical input power vs the magnectic induction moving electrons in the generator/alternator coils. Once those electrons are moving there is yet more loss in the resistance of the conductors (wires). Some systems have more efficient handling of the losses than others.

From that perspective - there is also a power conversion/energy conversion in food to muscle output. I am no health/fitness expert so, again, that subject is well outside of my wheelhouse.

On the subject of high motor efficiency - there are certainly some high efficiency designs out there. I am not sure what the overall range of efficiencies is, however. The higher efficiency designs wouldn't get as hot as lesser efficient designs when under the same load (less energy loss as heat). For the same battery capacity it should be obvious higher efficient motors will yield longer range.

All other factors being equal (weight, wind resistance, terrain, motor design) - the only way to increase range is to increase storage and charge capacities.

As to the ability to charge as you ride and the energy conversion - it would help to know what the conversion is between input power (added crank resistance) to electrical output (wattage). That is where the study on hub dyno efficiency would be interesting to factor in. I don't know if such a study exists, outside of manufacturers data (which is likely quite biased), for eBike systems and their ability to recharge under pedal power or down-hill cruises.

Another interesting point that was made to me in an earlier thread I had ( a few years back now) on this subject was to work with averages - the same point I made earlier regarding all types of alternative energy sources. However, the point on averages here also includes the point about the power output that is achievable while going down a hill. On large hills on tour (loaded) it is very easy to get moving real fast - 40+mph in some cases. I don't know about you, but you will never catch me going that fast. I'd probably have to check my pants if I got much north of 30mph. With that having been said - on those large hills - instead of braking it would be awesome to be able to boost charge current. If I have an excess of gravity propulsion anyway, to soak up as much of that as I can for a period of time that would be great. However, the reality, again going back to the point of averages, is that period of time of having an excess of gravity propulsion is very short. It would make a lot more sense to design a system that can operate on level ground under pedal power. It may cause too much drag to charge going up hills, and you may over power it cruising down a hill at full speed (that is an important note - many hub dynamo systems have burned up doing just that) but on flatter terrain you get a balance of drag vs power output.

How the eBikes are designed to work with averages I am not sure, I would be interested to see. However, what you want to try to find is what the added input resistance is while under charge as what ever that number is (or range) will add to your cycling wattage calculator results from before. Then from that number you can use what ever you find out from the caloric conversion to figure out a range of caloric intake to keep you going and charging.

Just to be quite frank - though it may be of interest to some, calculating caloric intake vs output isn't much interest to me. My philosophy is to stay above the hunger point munching through the day and doing a bigger lunch. I eat what I feel like, in other words. If I find I'm hungry and I have miles to make it means I stop and get some food in me - what ever my intake was prior to getting hungry wasn't doing it. I know there are more scientific ways to deal with caloric intake and burn but I just listen to myself and roll with it

Mark Hoaglund

Thank you for sharing Steve I find myself understanding & agreeing with you while learning more. I'll have to do a downhill coast test for drag coefficient with & without my stock Aosom cargo trailer. I cruise around 10-3 mph as the day wears on. Thus the ebike interest.

Mark Hoaglund

Carrying a 1-2 pound solar panel with battery didn't bother me when I weighed 330 lbs or now after Dr. orders at 200 lbs. Being able to pedal along without the hours waiting at the convenience fuel store or overcast days AC charging the battery banks elsewhere. I'm thinking 2.9 lb. waterlilyturbine.com and 7.3 lb Jackery setup so I can stay longer preferably in the rural countryside.

Mark Hoaglund

Went all in this touring season and ordered the Jackery 60W solar panel. Now I can camp indoors until the parks open in May. In the meantime time to go explore the horizon and limber up cycling. Today at 6am 35 with highs in the low 40s F.

Mark Hoaglund

I thought this explained the parsley vinger combo:

DIY: The Best Mosquito Repellent Spray (Organic & Safe!)

KC8QVO

I was out a couple days ago now (the 17th) on a day trip. It was cloudy and I was getting 170mA, or .17A, out of both my panels combined. In full sun I got 1.27A, or 1270mA, out of them. That is a little more than 1/10th the wattage.

The point - yea, its not much power, but even when its cloudy I can get some power.

If you have the same power conversion out of your 60w panel - that may get you close to an amp, 3/4 amp or so, of charge current when its cloudy. That is a pretty respectable amount.