stryped fired this volley in news:14e5d120-54ea-
:

So these are probably not good to use in a garage/shop?

Why? We were talking about heat per lumen. As far as I know, sodium
vapor lights are either the most efficient or nearly the most
efficient high-output lamps available, and HIDs are not far behind.

The quartz envelopes are not exposed -- they're contained in an outer
bulb. The bulb gets hot, but not that hot.

You want lots of light. You'll have to virtually cover the ceiling
with fluorescents to get the same light output.

LLoyd