There is no such thing as "Human Power". Animals don't generate power, they just transform it from food via a roundabout process that produces lots of waste. There's just no way this is the most energy efficient way
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> they just transform it from food via a roundabout process that produces lots of waste.
You mean like any other machine that generates power? A human on a bicycle, assuming a ~20% efficiency of converting food calories to muscle output, gets a gasoline equivalent 600-1000mpge (https://en.wikipedia.org/wiki/Bicycle_performance). And unlike a car, using a bicycle has health benefits.
Humans are a pathetically inefficient motor; Gasoline engines are around 30% efficient and battery-electric drivetrains are more than 90% efficient. A bicycle looks efficient because that inefficient motor is also pathetically low in power - a typical recreational cyclist can only sustain about 120 watts of output.
The leading vehicles in the Shell Eco-marathon routinely exceed 10,000 MPGe. PAC-Car II is the current world record holder, achieving 12,600 MPGe on hydrogen fuel.
Photovoltaic cells are also astonishingly more efficient than photosynthesis. The theoretical maximum efficiency of photosynthesis is ~11%, but most plants only achieve 3-6% efficiency. The leading commercially-available PV panels achieve ~22% efficiency and prototype concentrator PV cells have achieved over 46% efficiency.
Comparing these completely not road legal cars to technology from the 19th century is a stretch. I can legally ride my ~600MPGe bike on the streets TODAY. If PAC-CAR II equivalent cars are available to the mass market within our lifetimes, it will be impressive.
Electrically-assisted velomobiles are road-legal in most jurisdictions.
> 10,000 MPGe ... 12,600 MPGe
(0.024 l/100 km, 0.019 l/100 km)
> 600-1000mpge
(0.24 - 0.4 l/100 km)
Seems kind of pedantic. By this reasoning, almost all power sources are really fusion power, right? But we don't label solar, wind, fossil fuels, etc. as fusion.
The thing about human power is that exercise is also good for us, and in our current times most people (at least in developed countries) don't really get enough of it. So it doesn't necessarily have to be the most efficient to be useful.
It's not pedantic because of the inefficiency.
You'll have to use energy to produce and distribute the food that powers the people that power the things...
Perhaps you would be better off if you simply used the energy to power the things.
In the best case, you can think of it like regenerative braking. You're recovering some of the energy that would normally be wasted on exercise machines in the gym.
Perhaps the most sustainable way.
It would reduce my stress to imagine a world where my grandchildren didn't die from atrophy during the great power outage of 2079, where only the 10% of humanity that weren't reliant on exercise machines exercising their muscles for them, survived.
Come on Silicon valley - one up this please..