Viability

Can it be done?

Yes. As long as I can out-pedal my office’s biggest consumers:

  1. Laptop: 80w at peak. On 4-8 hours per day.
  2. Lamp: 20w constant. On 4-8 hours per day.
  3. Printer: 60w at peak. On 15-20 mins per week.

Clearly pedaling 100w for 8 hours stretches is not viable. So the plan is to produce more power in less time and store it in a battery. Build Your Own Wind Turbine.com suggested a home-made Hugh Piggott turbine would allow me:

  • produce decent levels of power
  • recharge a battery reasonably quickly
  • put up a wind turbine in the future (if I decided not to keep pedaling).

Given the resistances involved in larger diameter turbines, it was felt a 3m turbine would provide a reasonable proof-of-concept starting model. Here’s the initial test run in 2010:

Many kilometers and challenges later I am now confident that:

  • the idea is viable: overcoming inertia and resistance to reach ‘cut in’ speed was easier than expected.
  • pedaling can be sustained for a decent length of time: fourth gear on my racer, pedaling at about 21kph, produces about 16v. Sustaining that for 60mins or longer is easy enough. When I get watt meters installed I will post news about amount of electricity being created.
  • no need to kill a bike! This original video shows a mountain bike clamped into position. I’ve since replaced that with my far-more-comfortable-and-efficient racer – which sits into a training stand. Which means I can detach it and take to the road any time.

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