Wasn't that the second episode of Black Mirror?

It's still unlikely to pencil out to do this given the opportunity cost of actually going through the effort of building, buying and connecting these things, to be honest.

I'm fascinated by the idea but it's important to remain realistic.

Here's a good article on the concept of bicycle generators: https://solar.lowtechmagazine.com/2022/03/how-to-build-a-practical-household-bike-generator/

Personally, I think the best application of this concept is probably direct use of the mechanical energy, without converting the energy to electricity at all. See the bicimaquinas-concept: http://www.mayapedal.org/index.en

One of the wonderful things about bicycles is how extraordinarily efficient they are - very little energy is required in relation to how much transportation work you get out of it. This works against us in the case of power generation, though - little power going in means little power going out.

It's a really good business idea that I've had more than once -- a self sustaining "green gym".

Members would leave their electronic devices in special hardened lockers, plug them in, and then go to work out, and the power from central battery bank would then charge everything that's in the lockers.

I also had an idea for credit system where the more power you generated the cheaper your monthly bill/subscription would be for the gym (only a few bucks here and there), or some kind of perks, like a free t-shirt once a year if you generated over 1 MWh (1000 kWh) or whatever.

The power generated by such a place would probably be negligible but it would give people the same emotional high as other pro-social tasks.

Haha, I wish -- they call it the hour record for a reason!

I've got explosive short-term speed, but it doesn't last, and I get dropped within 20 minutes, as my power output dips below the optimized pros who can do 400W constantly for entire Tour stages.

I appreciate the comment though!

With abysmal conversion efficiency

True, I only included kJ equivalent because some countries use kJ on nutritional panels instead of Calories. Actual conversion rate of human energy stores to usable power is, at a guess, more like

Calories * 0.25 * 0.6 * 0.8 - dt

where t is time, d is the self-discharge rate of the battery, 0.6 is the efficiency of the generator, and 0.8 is the efficiency of the battery.

So, user better eat their wheaties.

So only about 30 years of constant pedaling.

It's not about saving money. It's about using the energy that would otherwise not be used, and incentivizing exercise. If I could keep my phone charged from exercising, that would be cool. But yeah the price point is quite high.

Maybe making a bike for half the price that can just plug into an existing inverter / battery would be more versatile then.

That definitely changed things a bit there.