On Thu, 12 Dec 2013 18:57:13 -0600, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

fired this volley in
:

Replaced 460 watt halide vapour bulbs with 160 watt LEDs -
and it is brighter now than with the ol;d lights - and instant on - no
buzzing - about $460 per unit


That's going to be an iffy payback. I have a number of those
metal/halide vapor lights in my high overhead in the barn... they've been
in almost daily service for me for over 18 years... never a replacement
ballast or bulb; And I bought them USED from a parking garage demolition
project in 1995. No telling how long they'd been in service there.

That being the case, they last at LEAST as long as the LEDs claim to, but
mine are only about $30 per lamp. I figger it'll take about two years to
save $430 in power per bulb on a difference of only 300 watts. And
that's if the LED lamps really hold up long enough to pay back. The
vapor lamps are proven, LONG-lasting technology.

Lloyd
The building is 8 years old. They have had several ballast failures
already. Payback should be less than 5 years . Perhaps the30? year old
units you have are higher quality than what was available 8 years
ago???. The light is also brighter, and at the same less harsh
(softer shadows) than the old light - and most of this is factory -
"work space". The LEDs are also a lot easier to reposition.