Whew! That’s a lot of figuring.
There are a couple of errors that you have made.
One horsepower is 550 foot pounds per second, not 150. So you’re off by a factor of 3.7.
I’m not sure why you want to pedal at such a slow speed. Three seconds per half revolution is 10 rpm. I’ve never seen a bike racer do that. I’m old, yet my most comfortable pedaling speed is 70 rpm or so.
The torque on the crank, and the pull on your chain, is going to depend on the length of the crank arm. If that was one foot long, you would put 150 ft lbs torque on the chain at two points as you pedaled— the two times your feet are level. If you’re just letting your weight pull the pedals around, there’s zero torque when the crank is straight up and down. You don’t notice this when you’re pedaling a bike so much, but the rpms of your generator will vary greatly as your feet circle the crank. I added weight to the rim of the wheel(20 pounds) to smooth this out.
That one horsepower motor would work, but it’s about ten times the motor you need.
Hey there!
I actually have my generator set up now! I went with
This Motor and it works great! I'm a little out of shape from the winter, but as of right now I'm able to produce about 60watts for two hours at a time. This works perfectly for me. At some point I think I'll post some pictures here to show what I came up with.
However I am having an issue. I sometimes get an overload(I think) that usually discharges some sort of shock...
Here is what I am working with:
I have my motor hooked up to my battery with only a blocking diode as was recommended, though right now the battery is only a single 12vt tractor battery that I am using for testing purposes. I have a 300 watt pure sine wave inverter hooked up to the battery as well, and am running my laptop off of that.
I get my battery up to 13.2 pretty quickly when producing 60 watts. This battery usually stays at about 12.5 when not charging and at no load. At about this time, every now and then, maybe every 15 or 20 mins, I will get a static discharge from the outside of my laptop (connected to the system via the inverter) that will shock me, though one time there was a shock in my battery volt meter that shorted it out, and I needed to reset it before it would display again.
My theory right now is that I am producing too much electricity for my battery at once. I believe this to be the case because my laptop only draws about 30 watts, and as I am putting 60 watts in and my battery is already fully charged. Also, If I only produce 40 watts, only enough to just put a little charge in and keep my laptop plugged in, I don't get too much of an issue. However once I try producing over about 55 watts, it starts discharging every now and then. And if I try going up to 70 or 80 watts, the discharges become much more frequent. Again, I am only going through the blocking diode, instead of a charge controller.
This is why I had originally thought I would need a charge controller so that I would not overload something, as when the battery is a different states in the charge in can only handle different amounts of charge, at different volts and amps, and I don't think I can control it that well with my pedaling only. If I go through a charge controller it will only let the amount through that my battery can take. Considering my wattage is varying bassed on the speed and effort that I pedal, when I am producing 60/70 watts, my voltage I am producing is about 13.8/9. And at 40 watts it is about 13.3/4, and my amps also vary between about 3 / 4, I feel a charge controller would be able to take that, and regulate it into a voltage and amperage that my battery can handle, and stop any overloading from happening.
So, I am here to ask if I am missing something. I know all my wiring is correct, the positives are not connected to the grounds in any way...
I feel like I should at this point just add in at least a small solar charge controller like
This one into the system.
Or am I missing something else obvious? But overloading my battery, in other words bringing it to a voltage it can't handle that quickly, seems to be the only thing I can think of that would cause a shock like that.
Any advice is appreciated.