There's a lot of factors to take into account there. First of all - would the balsa be longer than the playing cards? If not, you really only have a difference in mass of the blades. But I'd think you'd want something longer than playing cards.lllazar wrote:Ahh, so i'll need a generator and some probes as well? Thanks

And 1 last question, in a general way could you briefly explain what kind of design/material would produce more power and not just a fast rpm, like for example:

Would a balsa turbine that has the same rpm as a turbine made of playing cards produce more power?

The total power you can capture in the wind stream increases proportional to the square of the turbine radius:

However, rotational inertia and aerodynamic drag oppose the rotation of the turbine. If we assume the blades to be rods (fairly close) and use the radius r as the rod length, we find the rotational inertia of a single blade to be . So inertia also increases as a square of blade length.

You want to find the optimal length that maximizes your power captured.

Your generator will be the motor from a CD player. The probes should come with or be attached to your meter.