Hi:
I have been following the discussion on smoker fuels.  Here at Kona
Queen we used to use wood scraps.  It gave a nice smoke, but we use
literally tons of fuel every year, (fifteen full time beekeepers for
nine months of the year and nine for the other three months), and the
expense was enormous.
We now use a commerical product designed for a pellet stove.  This
stuff is pressed and extruded wood chips.  It kind of looks like
rabbit droppings.
We purchase it in bags on a pallet.  It is kind of hard to start, but
a lot of newspaper and some forced air from the compressor blown
through the bottom of the smoker fixes that problem.
The only modification to the smoker is the use of a screen on the top
to keep the "pellets" from blowing out the top.
This fuel with burn all day and even into the night.  I have had my
smoker stay lit for two days straight!