I just wanted to add a few numbers to my previous reply:
A 75 watt Sylvania BR40 has a rated life of 2,000 hours and produces
680 lumens of light, or about 9 lumens per watt. The efficiency of
this bulb (and others like it) is really very poor. Hopefully, one
day soon, they will disappear from the marketplace.
By comparison, the Philips 70 watt PAR38 IR referenced below, has a
rated life of 4,200 hours and produces 1,550 lumens (22 lumens per
watt). Watt for watt, this bulb offers 2.5 times more light and more
than double the service life. And, as previously mentioned, the
quality of light is far superior to that of any incandescent
reflector.
If dimming isn't required and if excess heat is a potential concern,
the CFL floods I use have a rated life of 8,000 hours and produce
1,280 lumens; this works out to be 55 lumens per watt, or SIX times
that of the aforementioned BR40. To properly light a large area as
you had described, this could very well be your best option.
Cheers,
Paul
On Fri, 24 Mar 2006 04:58:15 GMT, Paul M. Eldridge
wrote:
If your budget permits, I would recommend halogen PAR38s due to their
longer life, higher efficiency, better lumen maintenance and superior
light quality. For a little more money, you might also consider
halogen "IR" ("infra-red"), which offer even greater efficiency and
extended service life.
See:
http://www.nam.lighting.philips.com/...pdf/p-5761.pdf
This type of product is not generally sold at retailer outlets, so you
have to obtain them through a lighting distributor or electrical
supply house. I use 60, 80 and 100-watt GE versions in my home.
During the winter months, the waste heat from the operation of these
lamps helps heat my home; the extra heat is especially useful on the
basement level, where it tends to run several degrees cooler (currently,
here in Nova Scotia, oil and electric cost about the same, on a BTU
basis, so there is no financial penalty to choosing one heat source
over the other).
That said, come spring, when the extra heat is not welcome, I swap
them out for the CFL floods shown he
http://www.standardpro.com/product/g...t.aspx?id=4081
Amazingly bright at just 23 watts and excellent light quality (85
CRI). They are physically the same size as a standard PAR38 and have
a flat, hard, glass lense -- not plastic or soft glass like most CFL
floods. I paid $14.00 CDN ($12.00 US) per bulb, which I consider to
be a pretty good deal.
Cheers,
Paul