If you are considering large cfl's I would strongly recomend you at least
think about a small MH or HPS. Not only are CFL's very fragile and tend to
not last anywere near their rated life (Made in China) they are also only
about half as efficent as MH. On a watt per lumen basis hps and mh give of
twice the light and only half the heat. ie a 100W MH would give off the same
light as a 200W CFL and only a quarter of the heat. The big kicker is a
small MH is only about $50-$75 more and replacement cost on the bulb is
only about $30 Vs $85-$150. Unfortunaltly not that great for shelving
systems as all the light is coming from one source. HPS is even more
efficient but have an icky colour of light.

wrote in message
...
Here is a bit of what I have seen on the 200W CFL bulbs
The first one I ever ordered came broke right out of the box. The
spacers that are glued at the top of the tubes had come loose and the
bulb was cracked at the base. The replacement for it lasted about
three weeks then just did not light at all. I have had one other just
give up with less than 100hrs on it. And of course I have broken two
of them myself moving them around (one of them by putting it in a
fixture and one by it slipping in my hand and I tightened my grip and
it just snapped) The 200W are very fragile. I have 4 of the 200 watt
bulbs that have been running 18-20hr a day (two in fixtures and two
hanging in between rowes of shelving) a good bit over two years and
they still put out resonable lummes.
I prefer to use the next wattage down (the 125watt) because...
They are cheaper, put two together and you have more light at less
cost, less fragile, standard base socket and did I mention less
fragile?
I use them just hanging vertically from a socket on a cord.
Also the 200W runs pretty hot (not like the MH or HPS but still they
are hot) My personall opinion and unfounded non scientific reseach
says they run hotter than a 48" 4 tube light and if you have pots
above them they will dry them out in a hurry.
Again this is just my personal research and opinion, yours will very.