Lew Hodgett writes:

Things like inital cost, power costs, winter time temperatures, become
signficant issues.

The very first one you want to address is temperature since light output
is so temperature dependant.

The shop will be fully insulated, heated, and cooled. Temps will be kept
at 45 to 50 degrees in the winter.

I definitely want T8 fixtures with electronic ballast. 4' or 8' is the
real question. The 8' fixtures are more than twice as much as 4' fixtures
from what I have found to date.

Brian Elfert