A custom here in Minnesota is to dangle a light bulb near the water meter or any other water-carrying pipes that are in your unheated basement. You don’t need a switch. You just have a light socket on a wire, and at the beginning of winter you screw in a 100 watt light bulb, and at the end of winter, you loosen the light bulb so it stays off for the summer. This prevents the pipes from freezing and provides light in the basement at the same time.

This sort of practice has led me to wonder if compact fluorescents should be pulled out of some of the light sockets during the winter, and replaced with incandescent, because, after all, they are generating heat. I’ve wondered if this is in any way efficient.

Well, it turns out that it probably isn’t assuming you are heating your house with natural gas, and have a reasonably efficient furnace. How do I know this? By reading a blog post called Compact Paradox over at Thinking for Free.

Comments

  1. #1 Dan J
    June 3, 2009

    I remember the first time I went to switch a traffic signal to manual mode at a job I had years ago. Upon opening the box for the controls, I noticed a light bulb in a socket mounted in the base of the box. Hours later it finally dawned on me what the bulb was there for: to keep the box warm so that the internal mechanics didn’t freeze up in the winter.

  2. #2 6EQUJ5
    June 3, 2009

    Using bulbs like that is inefficient. I’ve wrapped hundreds of feet of steel pipe with heater tape, foam wrap, and duct tape. Plug in the heater tape upon the first frost, and unplug it after the spring thaw.

    The tape uses resistance heating which is highly efficient, and no power is wasted as light. Insulating the tape improves the safety margin.

  3. #3 khan
    June 3, 2009

    In Upstate NY in the 50s & 60, parents would put a light bulb under the hood of the vehicle parked outside in the winter (at least for the especially cold nights).

  4. #4 D. C. Sessions
    June 3, 2009

    The tape uses resistance heating which is highly efficient, and no power is wasted as light. Insulating the tape improves the safety margin.

    A light bulb is a resistance heater, and very little is “wasted as light” — they’re that inefficient. However, even what little is “wasted as light” ends up as heat in the basement anyway.

    However, you have the right answer for the wrong reason. The pipe-taping approach is much more efficient, but because it heats the pipes directly rather than trying to heat air, which mostly goes somewhere else, and a little bit of it getting to the pipe.

    For better results yet, it’s not that hard to rig a temperature-sensing switch to control the tape.

  5. #5 Bill James
    June 3, 2009

    As a factor of straight up economics, natural gas or propane being a much cheaper heat source than electricity which is one of the most expensive until you reach for solar etc. So yes, it would be cheaper to let the furnace heat the space enough to prevent freezing of water pipes providing you didn’t have to pay for retrofits. Either way, both methods being cheaper than repairs on a burst water pipe in unheated spaces at twenty below. I grew up in an old farm house. Been there, done that.

    As always, insulation is your friend and we wound up using heat tape for those few days (weeks) a year when it gets extremely cold. We just had to remember to plug it in. Interestingly enough it was always the hot water pipe that froze. Hopefully nobody runs water pipes along foundations in unheated crawl spaces anymore. But yes, we used incandescent light bulbs to keep things from freezing for a time including baby chickens, pigs, puppies, kittens, what have you out in the barn. Of course we also had regular infrared heat lamps for that as well. Not to close though.

    Which reminds me of an incident we had around here a few years ago having a small contingent of homeless guys who preferred to camp out on the shoals at the confluence of a river and a large stream. Offering little to no shelter from the elements the guys would build fires over the bedrock – favorite places being larger stone slabs – until the rock would build up enough heat to carry over the night. A blanket or two, perhaps a sleeping bag if lucky and maybe a plastic tarp of some fashion should the weather be inclement, the guys would lay upon the rocks for comfortable sleeping.

    This being a practice that continues to this day, on one frozen morning a more unfortunate fellow was found peacefully dead and quite well done having been slow roasted in his slumber. The Darwinian lesson to be learned I suppose is that you simply want to warm the rock and so too our small, furred and feathered friends.

  6. #6 daedalus2u
    June 3, 2009

    I found that if I turned off the pilot light in my gas furnace over the summer it made a noticable difference in my gas consumption.

  7. #7 Richard Simons
    June 3, 2009

    I had always wondered about this, but been ridiculed by the person who came to check the energy efficiency of our home. However, perhaps six months ago the CBC’s main news program had an item in which they (fairly superficially) looked at the cost savings of using fluorescent versus incandescent lights. They found that in some areas incandescent lights were actually cheaper to operate, at least in the winter, because of the reduction in heating bills. IIRC a major factor was the relative costs of electricity and oil/gas.

  8. #8 Bill James
    June 3, 2009

    daedalus2u: I found that if I turned off the pilot light in my gas furnace over the summer it made a noticable difference in my gas consumption.

    You have a pilot light?

    Richard Simons: …incandescent lights were actually cheaper to operate, at least in the winter, because of the reduction in heating bills.

    If a home used electrical resistance heating primarily, then the difference between incandescent and fluorescent lighting might be close to a wash in wintertime. Otherwise no. Even in these times of rising energy costs, the difference between electricity as a resistive heat source and natural gas/fuel oil remains too great.

    To make matters worse, an incandescent light bulb is significantly less than 100% efficient as a heat source while pure resistive heating is (for all practical purposes) 100% conversion efficient.

  9. #9 GaryB, FCD
    June 3, 2009

    In the Canuckville Midwest, where natural gas heating is the norm, we insulate (exterior and interior) and heat our basements. We only use bulbs under the hood of our cars when the block heater fails.

  10. #10 D. C. Sessions
    June 3, 2009

    To make matters worse, an incandescent light bulb is significantly less than 100% efficient as a heat source while pure resistive heating is (for all practical purposes) 100% conversion efficient.

    That’s a very low threshold of “significant.” Aside from light leaving by windows (a small fraction of a low efficiency) every watt of power used by a lamp ends up as heat in the room.

  11. #11 Bill James
    June 4, 2009

    D. C. Sessions: That’s a very low threshold of “significant…

    Heh… I guess it was and your quite right. I yield the point.

  12. #12 Lassi Hippeläinen
    June 4, 2009

    Amateurs. Here in Finland (60 degrees or more north), we use plastic pipes with a heating wire embedded inside the wall. Hook to a thermostat and surround with insulation. But mostly our basements are warm enough to prevent freezing. It also prevents problems with humidity and moulding. And the pipes in and out of the house are dug so deep in the ground that they are below frost.

    As young students in the seventies, we visited British countryside. We wondered why all the plumbing was on the outside of the houses. We were told that it is safe: you can melt the pipes with a torch without burning down the house. We were amazed by the ingenuity…

  13. #13 Dunc
    June 4, 2009

    As young students in the seventies, we visited British countryside. We wondered why all the plumbing was on the outside of the houses. We were told that it is safe.

    Also, a lot of that stuff was retro-fitted.

  14. #14 Greg Laden
    June 4, 2009

    Wait … doesn’t some of the light stay around as memories of what you saw!?!?!!?

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