Power your house entirely by pedaling a stationary bike connected to a generator! The only catch is that you have to do it for 24 hours per day, and then an additional 26 hours that same day.


It’s difficult to appreciate the amount of energy that is consumed by a citizen of a modern industrial economy.

If we only consider household electricity, a “reasonable” amount of consumption (ignoring air conditioning or heating) can be more than 5 kilowatt-hours (~200 watts of average usage over a 24-hour period).

A non-bicycling-enthusiast adult can generate ~100 watts for an hour (optimistically) before they get sick of it, for a total of 0.1 kilowatt-hours (Figure 1).

Fig. 1: In this scenario, a person pedals on the stationary bike (left), and this is somehow converted into stored energy in the battery (center). When you need power for the house, your plug the battery into the mains (blue cable) and… let’s just imagine this all works out somehow, I’m no electrician.

The Issue:

The numbers above give us the following totals:

  • Household power usage per day: 5000 watt-hours
  • Plausible amount of electricity generated by a human: 100 watt-hours.

In this particular case, we have a shortfall of 4900 watt-hours. A person would need to generate about 50 times more power than they actually do in order for the house to be fully powered by an exercise bike.

The numbers above aren’t even enough to keep a refrigerator operational!


The goal here isn’t to actually fully power a house with a stationary bike (since that’s clearly impossible).

But we can give a person an impression of how much power is actually consumed by various things, and encourage them to exercise by entirely cutting off electricity to the house if the inhabitant doesn’t pedal the bike sufficiently.

The process will work as follows: a bike will be connected to a (totally fake) battery with a screen on it (Figure 2). When the user pedals, the battery is “charged.” This is all simulated, except for one part: if the battery is completely drained, then the electrical outlets in the house will stop working entirely.

As you can imagine, this will provide a strong incentive for the user to frequently make use of the exercise bike!

Fig. 2: Here, we can see that the user has 9.6 hours of charge remaining in their battery at the current rate of usage. Note the “power multiplier” setting in orange, which is discussed in the following text.

In order to make this system actually possible (and not just completely demoralizing and/or equivalent to just having no electricity), we will include a “power multiplier” setting (the orange text in Figure 2) on the battery. This setting allows the user to get credit for vastly more electricity than they actually generated.

For example, if we set the power multiplier to 100x, then for every 1 watt-hour the user generates by pedaling the bike, we’ll add 99 additional watt-hours from the power grid.

In a location in which air conditioning or electric heating is required, the power multiplier might need to be increased to 500x or more.


It’s quite surprising how much power even a basic appliance consumes.

For example, one of those on-demand hot water kettles (the kind that can dispense scalding-hot water at any time) consumes an average of ~35 watts 24/7. So just pedaling a bike is actually not even sufficient for this single kitchen appliance!

A microwave or space heater will typically consume between 1000–1500 watts, so clearly that’s out of the realm of possibility unless we get an entire team of Olympic bicyclists to power it.

PROS: Encourages people to both 1) exercise and 2) consider energy efficient appliances.

CONS: None! The perfect plan.