Posted by chris on January 10, 2005, 6:24 pm
does anybody know where (on the web) i can get
specific information about the duty cycle and
efficiency information for fluorescent lighting.
ie, where is the break point between turning lights
off/on and leaving them on?
my office has been redone and now there are motion
sensors on the office lights to save energy. i would
contest that these sensors waste more energy than not.
people now leave their office lights on when they leave
thinking the sensors will turn them off. so for the rest of the day
and night people staying late and the cleaning
crew trip the sensors. The lights are then turned
on and off for hours. This can not be better than people
just turning off their lights, even after you account
for some % of people forgetting to do that.
Posted by SQLit on January 11, 2005, 1:38 am
I did 5 buildings at a "U" we saved in the neighbor hood of 30% on the
lighting. We upgraded the lighting to t-8's from the old t-12's. The new
ballasts used a tad less electricity. Hallways were a big saver not so much
in the day time but in the night time. Once the cleaning crews were gone the
lights were off. Our system might be different that yours. We removed all of
the light switches, so the motion sensors worked the lighting.
Lecture halls were the one of the very few places where there were switches
left after our upgrade.
Once the industry changed over to electronic ballasts the on and off
nonsense when away. Besides the technology on the lamps is a lot better than
Posted by Mike Swift on January 11, 2005, 6:55 am
A lot of noise has been made about the power used to start both
incandescent and fluorescent lamps, however there is very little extra
power used to start lamps compared to running them. Incandescent lamps
draw 4 to 5 times their running power when starting up, but if you go
through the numbers the increase caused by say 5 cycles at 500% of rated
power and then 3600 cycles (one minute at 60 Hz) at rated power the
increase in power is far less than one percent.
Posted by nicksanspam on January 11, 2005, 10:12 am
There's a small tradeoff between bulb life and energy. Each start removes
about 6 minutes from a fluorescent's 20K hour lifetime. If replacing a bulb
costs $, each start costs $.00001. Perhaps a bit more, with startup stress
on an electronic ballast.
Posted by Gymy Bob on January 11, 2005, 11:55 pm
Wow! Can you get these for $ each? ohh..you not talking CF then?