Wayne Lundberg wrote:

Take a look at the centrifugal speed controllers on the old steam engines.
The perfect solution in that they are simple, dependable, cost effective,
and will not hinder low breeze operations.... Two balls rotating and the
faster they go the tighter the pull on the brake lining. You can see the
same effect on small motor drives like in a scooter. Rev up the motor and
the clutch engages to drive the pup.

I think it'd blow the budget.