> Is there any advantage to
>multiple small units

reliability maybe

>(other than my small units only cost about $30 ea., a
>larger unit might cost more to build)?

cheaper than 2 small ones probably though.

>Could they be wired in series for an
>increase in low wind performance?

true but rather a hassle.

> Any other advantages/disadvantages?

disavantages include lots of fiddling about.

> Could
>they be set up to switch from series to parallel at higher wind speeds to
>prevent to high of a voltage?

yes in theory.
>
>Another question: If my generator is not properly sized to my blade, is it
>possible that a smaller blade would make more usable energy by virtue of
>increasing the rpm and, consequently, voltage?

yes if the alternator speed is away above the best speed for the blades.
Then you will probably do better with a smaller diameter, even though it
will catch less wind.
>
>just one more... Has anyone used a "golf cart" differential as a gear box
>for a slightly larger generator?

sounds like a lot of friction and maintenance.

Hugh

Scoraig,Scotland.
http://homepages.enterprise.net/hugh0piggott/

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