this is off topic, but is it possible you could charge the batteries for your EV with a stationary bike so your "gas" is your exercise you need anyways? or am i asking for 100 mile ride a night?

Would it be possible to pedal charge your electric car? not really, my figures show that it would take over 100 hours of pedaling at what would be simaler to ridding 20mph.
figure your electric car has a 210amp hour 120 volt battery pack (figure taken from a civic vx called the EVX converted to electric by Michael Hackleman), now if I remember right, amp hours times volts gives you watt hours, that battery pack would have 25,200 watt hours, from what I've read, riding a bicycle at 20mph takes about 1/4 horse power, acording to google 1/4hp is 186 watts worth of energy, or 135 hours of pedaling, assuming that your bicycle converts mecanical energy in to electricity without any losses, and that doesn't happen, ever, so if you want to fully charge your electric car, I would set aside a good month worth of 8+ hour days of pedel time, of course by the time you reach the end of the month you would be in good enough shape to make up for how out of shape you were at the begening of the month, and maybe make up for the self discharge of the lead acid batteries as well.

If your commute is like that of the average American and you bike about 1 hour a day, realistically, it will provide less than 1% of your car's electricity needs.

It's a good idea and has been done, but the total amount of power that you will be putting into the car is very small.


To put it into perspective, the average American drives about 35 miles per day. A typical midsize car converted to electric with no attention to aerodynamic efficiency(eg. Ford Taurus, Toyota Camry, Dodge Intrepid) will use about 250-300 Wh/mile from the batteries at a steady 60 mph and about the same amount in the EPA driving cycle if you have no regen. That's 8,750-10,500 Wh per day used.

Lets say you would ride an excercise bike for an hour a day, and at a modest amount of exertion, perhaps 100 W. That's 100 Wh made in that period by you. When you factor in generator efficiency, battery charging efficiency, you will get about 70% of that into the battery pack. So 70 Wh.

70 Wh / 8,750 Wh = .008, or 0.8% of what you would use.



You'd be much better served by investing in small wind turbines or solar panels, although using an excersize bike as a generator is a good idea and will supplement a very small amount of your needed power.

I knew Toecutter would come up with the answer to that one. :thumbup:

Me too. I actually started to answer and then thought, step aside... he's coming... :p

One place where you can recharge an EV by pedalling is if it's an e-Bike (if it has regen).

I rode a L-Ion bike in December. The pack was getting low, so just for fun I switched it into mild regen mode (such as what you might use when going down a long, gentle hill) and pedalled. You can add a useful amount of energy back to the battery this way.

OOoo! Imagine if you had a household where one person rode the e-Bike to work, and the other commuted by car and went to the gym for exercise.

You could just set up the eBike in regen-mode in front of the TV and have the car-commuter recharge the bike each night for the next day's use. Clean, renewable energy! :)

I've often wondered what would happen if gyms put generators on all their equipment to add resistance, insted of converting it to heat, Trace used to make a small grid intertie inverter that you would glue to the back of your PV panal, it then had a cord that you pluged in to any wall outlet, it sensed, and matched the grid, and backfed, I would think that one of these on a generator on a bicycle would work, fill a gym with these, and you would have peopl paying you to ride bicycle generators, sure it would be an added cost to the gym, but make it a "green" gym, and charge people more.

SolarDave on peakoil.com has an exercise bike that he uses to provide some of the electricity in his home. I think he runs a labtop off of it.

I've always wanted to make a bike with a hybrid electric assist.

As for the machines at the gym, most if not all commercial stationary exercise machines I've ever seen that have a control panel were powered by: (you guessed it) the user. They all seem to run generators and to add more and more resitance, they just connect smaller and smaller restistors across the generator output. I once saw the cover off one and there were a bunch of huge ceramic power resistors that apparently had gotten so hot they burned things around them. If only there was some kind of common buss that could be used to interconnect the machines and collect the surplus power to charge batteries or that could run the AC, or heat the water for the showers or something. It seems they're halfway there.

It's a pretty simple modification, but the payback period would be at least a few years.