I’ve decided to write this article because of the number of people defending a rather silly invention that someone developed a while back. No matter how much time I spend explaining it to the supporters, it just doesn’t sink in. This is warning to those out there who buy into an idea before really vetting it. Warning, this is as much a rant as it is anything else.
This article comes from True Activist. Apparently the authors need to take Physics 101. According to the article, the invention in question is a bike which can power a home for a full 24 hours on 60 minutes of exercise. But do the numbers add up?
First, recall from basic physics that energy in the universe is conserved (the actual law is a bit different, but we’ll use classical physics rather than getting into the differences involved in relativity). Now, these laws could be wrong. We shouldn’t be obsessed with rejecting an argument against them. However, let’s assume that there is no such argument against them. That means no matter what we do, we cannot get more energy out then we put in. In the case of this bike, the only source of energy is the human body.
So how much energy does the human body take in? The averaged recommended daily caloric intake is about 2,000 Calories. That’s a little bit under 100 watts. In other words, even if we converted all of the energy we consumed in the day, to an hour’s worth of working out, and that energy is stored with no loss, we could at best power a 100 watt light-bulb for the day. Now, the average annual electricity consumption, in China (this works as a low end estimate) is about 3,500 kilowatt-hours a year, or about 400 watts. So if we wanted to cover only half of that, we would need a 4,000 Calorie diet (again, assuming 100% efficiency).
What does a 4,000 Calorie diet look like? Here’s one option.
4 bagels @ 245 Calories
4 quarter pound beef patties @ 208 Calories
3 fried eggs @ 90 Calories
4 servings (1/4 cup raw ea) of black turtle beans @ 150 Calories
2 servings of spaghetti (about 1 cup cooked ea) @ 221 Calories
4 servings of pork belly (about 1 oz ea) @ 147 Calories
1 jelly doughnut @ 289 Calories
Total Calories = 4001
Now, it’s certainly possible to eat that much. Many weight lifters do. However, for the average person, that’s kind of absurd. What’s more absurd is that this is being marketed as an alternative energy source for people in third world nations. Sure, the energy requirements might be less, but food scarcity and malnutrition is a major concern. Who thinks it would be a good idea for a malnourished person to be engaging in an extreme workout in order to generate some electricity?
Basically, solar power, nuclear, bio-fuels, etc, along with the production of an energy grid is a much smarter and effective idea than this one.
