Generating Portable Power by Bicycle

December 17, 2010

In an era when an abundance of items requires electrical or battery power to operate, what happens when you aren’t near the grid or – heaven forbid! – the power goes out?

There are some interesting portable power generating options are available that generate electricity from the sun or wind or by simply pedaling a stationary bicycle.

We begin with the do-it-yourself version of power generation: the bicycle. Convergence Tech manufactures the Pedal-A-Watt, a bicycle stand that not only generates electricity, it seconds as a fitness device. The power that’s generated can be used to power lights and/or other small appliances, such as laptops, cell phones, fluorescent or LED lights.

As Convergence Tech writes on its website “Any bicycle that is in good shape will work with the Pedal-A-Watt Stand as the stand adjusts to fit any wheel size including children’s bikes.”

The company says the average rider can produce between 125 and 300 watts using the Pedal-A-Watt. While this amount of power isn’t huge, many pieces of equipment draw very little power and can be powered for long spans of time with small amounts of power. As an example, a laptop draws 70 watts, thus one 20 minute workout could run the laptop for over an hour.

The assembled Pedal-A-Watt (includes blocking diode) allows the owner to drop a bicycle into the stand, pedal and generate watts. According to Convergence, “The Assembled Pedal-A-Watt includes the bicycle stand, generator, 20 amp blocking diode, adjustment knob and instructions. The Pedal-A-Watt is built with off the shelf components to reduce waste and carbon footprint. The stand weighs 23 lbs.”

Convergence Tech sells the Pedal-A-Watt assembled for $399. It also sells other products of interest, such as an LED Strip (see photo on left). Using a Pedal-A-Watt is simple: the bike’s rear wheel spins the generator. The electricity that I generated can be used immediately or stored in a battery.

This information from the website will help in understanding the device’s capacity:

The Difference Between Watts and Watt-Hours:

If I am pedaling and creating 200 watts of power and I keep pedaling for 2 hours, I create 400 Watt-Hours, or: 200 Watts x 2 Hours = 400 Watt-Hours

With 400 Watt-Hours stored in the battery, a person can power:

  • A 400 watt TV for 1 hour (400 Watts x 1 hour = 400 Watt-Hours)
  • A 200 Watt TV for 2 hours (200 Watts x 2 hours = 400 Watt-Hours)
  • A 20 Watt laptop PC for 20 hours (20 Watt x 20 hours = 400 Watt-Hours)
  • A 15 Watt fluorescent bulb for almost 27 hours (15 Watts x 26 hours = 400 Watt-Hours)

Convergence writes this is the power consumption for typical appliances:

  • Small TV 100 watts
  • Large TV 200 watts
  • Laptop PC 10 watts
  • Desktop PC 75 watts
  • Stereo 20 watts
  • Charging a cell phone 5 watts
  • High-efficiency desk lamp 15 watts
  • Refrigerator 700 watts
  • Dishwasher 350 watts
  • Dryer 400 watts

Next time, we will look at portable solar power generators.



Glenn Meyers

Writer, documentary producer, and director. Meyers is a contributor to CleanTechnica, and founder of Green Streets MediaTrain, a communications connection and eLearning hub. As an independent producer, he's been involved in the development, production and distribution of television and distance learning programs for both the education industry and corporate sector. He also is an avid gardener and loves sustainable innovation.