3 ms·

Free Electric: A Bicycle That Will Power Millions of Homes

1 points by JSeymourATL 11y ago

gus_massa 11y ago
The name is misleading (I'd like to use a stronger word here). The electricity is not "free", the person that pedals has to eat and the food cost money. If they are going to install this in a gym, perhaps we can count that as "free". If they are going to install this in a developing country during a famine, then it's not "free" at all. Two very bad paragraphs: > “A person pedals the hybrid bicycle,” explains Bhargava. “The bicycle wheel drives a flywheel, which turns a generator, which charges a battery. Pedaling for one hour yields electricity for 24 hours with no utility bill, and no exhaust - no waste.” Ignoring that you have to pay for the food, a person on a bike at full speed burns about 700 kcalories/hour, i.e. 800 watts. Just assume that all the energy burned by the person is stored in the battery, this is very very very optimistic. If you want to use the electricity for the whole day, you can use only 1/24 of the power, i.e 30W, that is only enough for one or two new low consume lamps. > That’s right so many people – over half of the world’s population – don’t have heat, lights, air conditioning, cell phones, computers or televisions. Yes, this invention will help give more people access to energy that is free and clean. An air conditioner uses 1000W. So with 1 hour of biking at full speed and assuming perfect efficiency, you can turn on the air conditioner for 50 minutes. (Are you biking inside the room with the air conditioner?) Perhaps someone can charge a cell phone with this, but the other applications are not possible.
dalke 11y ago
An bicycle powered generator is an expensive way to turn human food calories into electricity. In the Middle Ages they raised dogs to run on a treadmill for hours, to turn the spit. See https://en.wikipedia.org/wiki/Turnspit_Dog https://en.wikipedia.org/wiki/Turnspit_Dog . That would be a more efficient way to power a generator, since dogs will eat things that humans won't. We don't - because it isn't cost effective. Buy a solar charger instead. A 100W solar panel is cheaper than this pedal-powered generator, and will produce power all day at no extra cost. > How many homes would it power up through the efforts of many gym buffs? Zero. Here is is worked out - http://michaelbluejay.com/electricity/bicyclepower.html http://michaelbluejay.com/electricity/bicyclepower.html . The human won't even be able to heat the shower used to clean up after cycling.
- gus_massa 11y ago
  Nice link. This idea reappears from time to time and each time I have think if I can write a small rant to explain why it's wrong. I'll bookmark this for the next time :(.
  - dalke 11y ago
    You can also point to https://www.youtube.com/watch?v=S4O5voOCqAQ https://www.youtube.com/watch?v=S4O5voOCqAQ .

1 points by JSeymourATL 11y ago

The name is misleading (I'd like to use a stronger word here). The electricity is not "free", the person that pedals has to eat and the food cost money. If they are going to install this in a gym, perhaps we can count that as "free". If they are going to install this in a developing country during a famine, then it's not "free" at all. Two very bad paragraphs: > “A person pedals the hybrid bicycle,” explains Bhargava. “The bicycle wheel drives a flywheel, which turns a generator, which charges a battery. Pedaling for one hour yields electricity for 24 hours with no utility bill, and no exhaust - no waste.” Ignoring that you have to pay for the food, a person on a bike at full speed burns about 700 kcalories/hour, i.e. 800 watts. Just assume that all the energy burned by the person is stored in the battery, this is very very very optimistic. If you want to use the electricity for the whole day, you can use only 1/24 of the power, i.e 30W, that is only enough for one or two new low consume lamps. > That’s right so many people – over half of the world’s population – don’t have heat, lights, air conditioning, cell phones, computers or televisions. Yes, this invention will help give more people access to energy that is free and clean. An air conditioner uses 1000W. So with 1 hour of biking at full speed and assuming perfect efficiency, you can turn on the air conditioner for 50 minutes. (Are you biking inside the room with the air conditioner?) Perhaps someone can charge a cell phone with this, but the other applications are not possible.

dalke 11y ago

An bicycle powered generator is an expensive way to turn human food calories into electricity. In the Middle Ages they raised dogs to run on a treadmill for hours, to turn the spit. See https://en.wikipedia.org/wiki/Turnspit_Dog https://en.wikipedia.org/wiki/Turnspit_Dog . That would be a more efficient way to power a generator, since dogs will eat things that humans won't. We don't - because it isn't cost effective. Buy a solar charger instead. A 100W solar panel is cheaper than this pedal-powered generator, and will produce power all day at no extra cost. > How many homes would it power up through the efforts of many gym buffs? Zero. Here is is worked out - http://michaelbluejay.com/electricity/bicyclepower.html http://michaelbluejay.com/electricity/bicyclepower.html . The human won't even be able to heat the shower used to clean up after cycling.

gus_massa 11y ago
Nice link. This idea reappears from time to time and each time I have think if I can write a small rant to explain why it's wrong. I'll bookmark this for the next time :(.
- dalke 11y ago
  You can also point to https://www.youtube.com/watch?v=S4O5voOCqAQ https://www.youtube.com/watch?v=S4O5voOCqAQ .