Turn calories into electricity?

[leftbrainstuff]

A human athlete at the peak of performance can generate about 750W cycling. It's not much but what sets us apart from other land animals is our ability to do this for many hours nonstop.

I know because I supervized several research projects with similar hypotheses. Perfectly feasible but mostly impractical. Solar won out in all cost benefit analyzes.

The equivalent in solar panels would be in the order of 2 - 3 kW taking account of useful solar load per day.

So theoretically you could supply all your power needs from a cycle generator.

Practically you'd have no time for anything else.

[a64pilot]

I believe a Pro cyclist can maintain 400 watts for an hour, a regular but practiced cyclist more like 100 to 150, and most of us could maintain 75 or there about. I think I could make 25

Maybe a sprinter could hit 750 in a sprint
750 is 1 Horsepower? I don't think many could make a horsepower even for very short times

[newhaul]

Originally Posted by leftbrainstuff

A human athlete at the peak of performance can generate about 750W cycling. It's not much but what sets us apart from other land animals is our ability to do this for many hours nonstop.

I know because I supervized several research projects with similar hypotheses. Perfectly feasible but mostly impractical. Solar won out in all cost benefit analyzes.

The equivalent in solar panels would be in the order of 2 - 3 kW taking account of useful solar load per day.

So theoretically you could supply all your power needs from a cycle generator.

Practically you'd have no time for anything else.

Practicality is you can do some good for your power needs while getting some exercise on a passage.

[Sea Dreaming]

Originally Posted by Mike OReilly

I’ve never heard of any such installation. I came across this stuff early on in my pre-cruising life, and still have it bookmarked. Like you, I thought it sounded like a good idea, but also like you, I have never found a reasonable way to incorporate it into our boat life.

I remain interested.

Use it to power an ice cream maker or blender....eh, never mind. Both could be direct drive.

[Stumble]

The only peddle powered boats I am aware of is the big maxi solo trimarans like IDEC of BP. They use a bike hooked up to the winches to trim the sails. Otherwise I doubt it could be mounted reasonably, or provide more than a nominal amount of power.

[Don C L]

Originally Posted by newhaul

You would be better off by far to use a dynamo for pedal power
300W Generator Dynamo Permanent Magnet - Pedal Power Generators

This one really piqued my interest... perhaps it could work. Personally I am not trying to heat coffee, that's pretty dumb. I just want to keep my battery topped off...( and burn off a little belly fat..)...it has very fairly low demand on it so my 0.18 hp should probably do the trick!!

[sailorchic34]

Peddle power is pretty much a non starter for any major power generation. A person in good shape might produce 150 watts and an hour. I top cyclest maybe 500 watts for an hour and then be spent. eddy merckx in his hour record in the Mexican velodrome, produced about 700 watts. But that was Eddie.

If staying in shape cycling wise, perhaps a hobie kayak with the peddle powered thingy. Or make a peddle powered dinghy. That would be slow going.

[newhaul]

Originally Posted by Stumble

The only peddle powered boats I am aware of is the big maxi solo trimarans like IDEC of BP. They use a bike hooked up to the winches to trim the sails. Otherwise I doubt it could be mounted reasonably, or provide more than a nominal amount of power.

One of these would make a great.tender.
Pedal (Paddle) & Electric Boats by Nauticraft

[StuM]

Originally Posted by CaptTom

I'm also curious. I'd like to see the math on this.

I recall pedalling a demo bicycle hooked up to a generator, and a few light bulbs. You had to pedal like crazy just to get a couple of them to show more than a dim glow.

From this totally unscientific experiment I concluded that it's probably not worth it. I would love to be proven wrong.

I did the math on this in a previous thread:

A TDF professional cyclist sustains about 300W over the race.

An "average fitness guy" can probably sustain about 100W over an hour of vigorous workout on an exercise bike.

So about 8Ah per day if you are prepared to do that 1 hour workout daily.

[newhaul]

Originally Posted by StuM

I did the math on this in a previous thread:

A TDF professional cyclist sustains about 300W over the race.

An "average fitness guy" can probably sustain about 100W over an hour of vigorous workout on an exercise bike.

So about 8Ah per day if you are prepared to do that 1 hour workout daily.

Cool thanks Stu . Thats almost the 10ah I loose daily with my 100watt solar when.im running my.fridge and lights. I already have.a.folding 6 speed bike so a couple hours of peddling sounds just about right .

[StuM]

Originally Posted by a64pilot

I believe a Pro cyclist can maintain 400 watts for an hour, a regular but practiced cyclist more like 100 to 150, and most of us could maintain 75 or there about. I think I could make 25

Maybe a sprinter could hit 750 in a sprint
750 is 1 Horsepower? I don't think many could make a horsepower even for very short times

The best TDF sprinters peak at around 1500W in the final sprint for the line. But they can't keep that up for very long at all.

[StuM]

Originally Posted by Stumble

The only peddle powered boats I am aware of is the big maxi solo trimarans like IDEC of BP. They use a bike hooked up to the winches to trim the sails. Otherwise I doubt it could be mounted reasonably, or provide more than a nominal amount of power.

Yep, a much more stable platform that your average monohull
And the purpose of them is to maximize the efficiency of short high power bursts for trimming etc, not for general power generation.

[Stumble]

Originally Posted by StuM

Yep, a much more stable platform that your average monohull
And the purpose of them is to maximize the efficiency of short high power bursts for trimming etc, not for general power generation.

Ya, the pedal power is for the 15 minutes or so it takes to trim the sails after a tack, electricity comes from the towed generators and solar panels.

[adoxograph]

Originally Posted by Don C L

So until that other thread was closed I was hoping to see if anyone had some working human powered generators in action on their boats and how they are working out. We are probably talking about the pocket cruiser crowd, but there may be others?

I think the Romans, the Greeks and the Vikings were quite successful with human powered boats.

[meatservo]

If there was a way to harness all of the hot air and bullsh*t coming out of Washington this past 8 years, we would be energy independent...




meatservo