I love riding my bicycle and would like to do it more in the wintertime. I was wondering if I could power my computer or my TV with a bicycle generator? How many calories would you burn?
Addicted to My Bicycle
Dear Addicted to My Bicycle,
To answer this question, you need to know two things: How much power does a computer or a TV consume and can a person generate that much power with a bicycle?
If you have a normal desktop computer and monitor sitting on your desk, then it probably consumes something around 200 watts. With a bigger monitor, it probably closer to 250 watts, but 200 is a good average. A large color TV consumes about the same amount of power.
Here’s a quick and dirty on how horsepower works: 1 horsepower is equal to 746 watts, so a person would have to generate about 0.27 horsepower to power a computer. Assuming that the generator is not 100-percent efficient, this means that a person would have to generate about a third of a horsepower to run a desktop PC or television.
Unless you are an Olympic athlete, it would be tough for you to generate a third of a horsepower on a bicycle for any substantial length of time. A “normal person” might be able to sustain a third of a horsepower for about half an hour before falling off the bike from complete exhaustion.
One solution to the problem would be to use a laptop computer instead of a desktop PC. Because laptops are designed to run off batteries, they are very efficient. A laptop might consume 15 watts. It would be extremely easy to generate 15 watts (0.02 horsepower) on a bicycle.
How many calories would you burn by doing this? To generate 1 watt for an hour, you burn about 0.85 calories. Rounding up, that’s about 1 calorie per watt-hour. So, you would burn about 15 calories per hour using your bike to power your laptop. At that rate, a single 60-calorie chocolate-chip cookie could be eliminated by powering a laptop for a mere four hours!
You are certainly on to something. I have a feeling this technology is not that far away. I wonder how that would affect our television time, should technology create something powered or operated only using a bicycle. Imagine the power we would save and calories we would burn every day!