Bicycle Powered Generator

[Rob Pope]

I want to put together a Bicycle powered generator to power a tv. I have
looked at the various sites on the web and need a few recommendtaions.

I am going to build it using a exercise bike, generating power and putting
into battery (ies) then running an inverter into the tv.

Any suggestions for a generator, ampmeter would be appreciated.
Thanks,Rob

 

[Kevin]

There was an article in "Home Power" magazine within the last year by
someone who did just this. He used a recumbent excersize cycle and the gen.
was a motor/gearbox from a powered wheelchair. I think he used a battery to
regulate his output to a 12volt portable tv.

Kevin
VE1TV

 

[Ian Stirling]

I want to put together a Bicycle powered generator to power a tv. I have
looked at the various sites on the web and need a few recommendtaions.

I am going to build it using a exercise bike, generating power and putting
into battery (ies) then running an inverter into the tv.

Any suggestions for a generator, ampmeter would be appreciated.

For reference, my 19" colour TV uses around 60W.
Tiny BW portables may use well under 20W.

For a generator, pick a 12V permenant magnet motor with a max rating of
twice the power you want out.
Work out a comfortable pedalling speed, and arrange gearing to run it
at it's nameplate revs plus a hair.

Now, attatch this with a diode to a 12V battery, so the motor doesn't
spin when you stop.
Take the inverter, and attatch through 2 diodes (assuming that the
low-voltage cutoff is 10.6V (this reduces wear on the battery)) to the
battery.
Now, pedal for a bit and turn the inverter on.
You may want to add a resistor in series with the motor to enable you to
pedal a bit faster without problems.

An ammeter to ensure the motor does not go over its nameplate amps is a
good plan, as is a voltmeter to measure the battery state.

 

[Rob Pope]

Thanks for the Info Ian & Kevin

I would like to run the tv + converter which would likely be a total of 80
watts about twice as long as I pedal. This is strictly an interest /
exercise program. I was hoping someone would have a make / model / specs
for the permanent magnetic motor I should be looking for and the best spots
to look for one. I think I can pick up the electronics from a local Radio
Shack.

Thanks

 

[Q]

I've tried several types of PM motors as bicycle generators. The best was
from an electric weedwacker. The motor was actually an 110 VDC motor with a
bridge rectifier in the circuit.

Q

 

[Steve Spence]

you can find this info at http://groups.yahoo.com/group/hpwd/

a permanent magnet motor, a set of volt and ammeters (25 amp, custom shunt)
from radio shack, a deep cycle battery, and a 300 watt inverter will set you
up.

 

[T.Jason]

I used a standard upright exercycle and four bicycle lighting generators
(actually magnetos putting out AC) to run a 5 inch B/W TV. It worked fine
as the portable TV was tolerant of non spec DC voltages (It had an option
for DC cell battery power). I used a 4 diode bridge rectifier for each of
the small magnetos that were mounted about the driven wheel. Then all of
the DC outputs were connected to a sizable electrolytic filter capacitor. If
I remember correctly, I connected 2 generators in series and those two sets
in parallel to obtain the needed 12 volts at load for my TV. Ideally I
might have used a small rechargeable battery as well. It would have been
advisable to use a voltage regulator to maintain the level of volts or open
a relay when the level fell below the specification for the TV. For the
month that I used it without regulation it didn't burn up my TV however. The
drag on the bike was noticeable but not overly difficult. The magnetos did
make some tire noise but not oppressively so. An ugly (I should have boxed
the electronics.) but very satisfying project. The low point for the project
was that the execycle seat was horrid.

Terry

 

[cw]

I found an upright exercycle with a 15" dia by 1" iron flywheel in front,
mounted an auto alternator on the upright handle column with a bracket made
from found bedrails, used a found serpentine belt for the drive, added a
found lawn tractor battery that was still good, then with a little drilling
and bolting mounted all this together. The wiring is positive output to the
battery, negative from the battery back to the alternator mount, the two R
and F leads from the regulator twisted together to a switch that then goes
back to the positive terminal on the alternator.
I used my purchased inverter from the battery to drive the AC loads.
I have found a reclining exercycle and just have to pick it up.
The effort required to pedal once the alternator begins generating is
noticeable but not overwhelming. One rpm of the pedals = 20 rpm on the
alternator. Once I begin pedaling, and get to about 80 rpm, click the switch
on the R-F to power the alternator and you are off. All in all it is not
that ugly, not that expensive, not that sophisticated nor that difficult, it
is all "off the shelf" parts easily found or purchased and required only a
hacksaw, drill, common wrenches and most of all, minimal skill.
It is great exercise, about like pedaling up a slight incline on a regular
bicycle, it is educational especially for my young nephews to see their
efforts translated into electric power.