Replace old Fluorescent ballasts?

[mattl]

I'm trying to track down what is using so much energy around the house and have been slowly working my way through checking what I can.  In my basement over my washer and dryer I have a nook with 2 40 florescent tubes.  It's old, from the early 70's when I built the walls and tucked it up out of sight.  Put my kilowatt meter on it and found it is using 100w.  the 2 bulbs add up to 80 so the extra 20 is heat in the ballast.

 

I'm wondering if the new electronic ballasts are much more energy efficient, enough to warrant replacing the older ones.  This light is on a timer and it's on 14 hours a day, seems I picked up a replacement for one of the other lights for $8 or $10 a year ago.  If I cut the power loss in half I'd save about $5 a year , so a 2 year payback based on it wasting 10 watts instead of 20.  Does anyone know how much more efficient the new electronic ballasts are?

 

[tolivac]

A new fixture with T8 32W bulbs and electronic ballast would give more light at less power draw-would draw less than your present dual tube 40W overhead lamp.Lowes and just about everyone has such fixtures-you are hard pressed to find core and coil ballasts in flourescent fixtures nowadays.All of the fixture makers are putting electronic ballasts in their fixtures-and the old T12 bulbs are slowly being phased out.the T8,T5 bulbs are more efficient-give more lumens per watt.for the price and hassle of replacing ballasts-would be easier and probably cheaper just to replace the old fixture.

 

[mattl]

Thanks, but in my case I sort of built it in, so replacing might be difficult.  Even getting to the ballast might be hard.

 

My laundry, computer, semi kitchen area of the basement has lots of florescents,  1 set of 72" single pin T12, a 4" overhead with 4 tubes I don't use much and the 2 tube setup over some of the laundry equipment.  I have plants growing under the 4' tubes, and I use the 6' set frequently when using those machines or ironing so it might make sense to update at least some of them.

 

[peterh770]

I know that you can no longer get the ballast for the 4" T12 4 bulb troffers any more, or at least without much searching and paying a premium.  This is forcing people to upgrade to T8 or T5.  I do admit, the skinny T5s are cool and seem to be much brighter...

 

[arbilab]

The amount of heat/waste from an electronic ballast is likely in the range of a nightlight or 7W, for a net saving of 13W. Now multiply that up by hours and your electric rate, will show you the savings and how long it will take to pay for the EB.

 

[sudsmaster]

I'd board up the built in fixture (after disconnecting it) and replace it with a shop light such as the Lights of America dual 4" T8 shop light fixture ($15 at Costco). It comes with a plug-in line cord and a on/off chain switch. I stuck mine on a motion sensing timer that plugs into an outlet, easily available from Harbor Freight or elsewhere, so it only comes on when needed. That measure alone could save you the cost of a new fixture. The T8 tubes use 8 watts less power than the older T12's, and put out more lumens as well.

I'd be a bit leery of a built-in fluorescent light fixture that is constructed so you can't get to the ballast anyway. I've had old magnetic ballasts in my workshop short out and partially melt down. They seem to be filled with some sort of tar-like substance. Fortunately they were in 8' fixtures that were suspended some distance from the rafters. But not something I'd want in a sealed up space.

I have purchased an number of these T8 shop light fixtures as alternative lighting in the shop - the fixtures that were installed years ago are rather energy gobbling dual 8' fixtures, running the length of the shop (about 50') in three parallel rows. The wall switches control three such fixtures at a time per switch (480 watts per switch). I've calculated that if all the lights are turned one at once, they would consume nearly 3,000 watts. By installing individual 4' energy efficient fixtures that I can turn on or off manually, or put on motion sensors, I can cut that power consumption down considerably by lighting areas only when needed. At the very least I can use about 64 watts to light an individual area vs. 480 watts using the original lighting.

 

[tolivac]

the T5 bulbs do give the most lumens per watt-and they are brighter.The T5 fixtures and bulbs are mose expensive than T8 type fixtures.the bulbs are not interchangeable-You need to get a fixture with a ballast that is designed to work with T5 bulbs.I like them too,they were first introduced for commercial lighting.Its high time commercial lighting equipment be made more availalbe for home use-many of the home type fixtures are inefficent,outdated and ineadequite.I like the min HID type tract lighting fixtures-you see them in many food stores over the produce-these would be GREAT to use at home and draw less power then the halogen bulbs.At work under our antenna switchbay we have dual bulb T5 fixtures-compared to the old incandscent fixtures these T5 ones-WHO Brought the sun in?they are great!they are enclosed weatherproof lights-would be nice in a shop or a kitchen.

 

[sudsmaster]

The oldest design is the 1-1/4" diameter T12 bulbs. These have lumen/watt efficiencies of 81-85.

 

Next up is the T8, which has lumen efficiency of 85 to 89.

 

T5 regular output bulbs can have efficiency of 96 to 102. High Output T5 bulbs have efficiency of 83-93. Not much better efficiency  than regular T8 bulbs, just more light per square foot of light fixture space.

 

The advantage of my new T8 shop lights is that they work at low temps (the T12's don't work very well) as well as being about 10% more efficient.

http://www.lrc.rpi.edu/programs/nlpip/lightingAnswers/lat5/pc1a.asp

 

[peterh770]

I just updated 5 4 bulb T12 troffers to T8 at one of my stores.  Hard work, but easy to do.  I have 2 extra on the side awaiting for either the remaining T12 fixtures to blow their ballasts or the T12 bulbs become unavailable.

 

BRIGHT!!!!