After reading the posts about the bulb y'all addressed all of my questions
about heat and coverage but the total cost issue still has me puzzled.

If I buy a 200 watt bulb and fixture the energy consumption would be the
same as a metal halide or HPS of the same wattage. It sounds as if the 200W
CF would cover the same area as the 400W MH so operational energy cost would
be 1/2 to cover the same area. Since the compact flourescent generates less
heat than MH or HPS the cost of cooling would be less.

The bulb replacement cost appears to be more than the 400W MH I used to use.
It sounds as if the 200W CF would cover the same area as the 400W MH.

So the TCO (Total Cost of Ownership) would be the cost of the fixture (lower
than MH), plus annual replacement of the bulb (about twice the cost of MH),
plus energy costs (1/2 of MH), minus the reduction in cooling cost (CF is
cooler than MH).

Overall it sounds like the CF would have the better TCO. Am I reading this
right?

Good Growing,
Gene