My Appliances are in Heat

That is to say, they’re inside the heated space in my home and it’s heating season.  I can therefore use them all I want, or leave them on when I’m not using them, and it costs me nothing in energy use.  I wrote about this a while back, and Say Uncle has a post that touches on the subject.

There are some qualifiers though.  A dishwasher dumps warm water outside the heated space, as does a clothes washer.  A dryer dumps hot air outside the heated space too, but you can leave your television or oven on all day and it costs you no extra energy useage.  If the appliances or the incandescent lights aren’t heating your home, the furnace takes over and uses that same amount of energy anyway.  I submit that using the appliances more may actually save energy.  Here’s how I got there; at least in my case, the furnace ducts are under the house, outside the heated space.  Some of the losses from that extra-hot air running through the ducts under the house might be avoided by keeping the heat generation all inside the house.  There was also a chapter in my college physics book that explained how inductive loads may be getting you some free energy, because of the way the metering works.  I forget how that happens, but if it’s true then over-use of motors and transformers (florescent lights or anything that uses a power supply transformer) as opposed to relying more on the resistive loads in your electric furnace may be saving on your energy bill.  Though that particular difference would be very small for a single home, IIRC the physics book says that this difference, this un-billed energy, is significant on a large scale.

If you want to save energy this heating season, using CF bulbs, turning off your lights, and using super efficient appliances (with the above caveats) isn’t the way to do it.  Not during the heating season.  Tightening up the house, adding insulation, using a heat recovery system on your dryer vent, etc., using less hot water (assuming that water’s being dumped outside the heated space) or turning down the thermostat, will save energy.  Otherwise, don’t let ignorance and simplistic thinking influence your lifestyle.

Someone mentioned last time that some of the light from your evil incandescents (or any other lights) is being lost through your windows.  True, but the visible light is a small fraction of the total output unless you’re using LEDs.  In any case it’s the energy you don’t see that’s being lost in far greater quantity through your windows, and that loss takes place whether or not your lights are on.  Use double or triple panes, and close your blinds at night.  We use opaque (to visible and IR) venetian blinds.  My friend, who I helped build a house on the Yukon/Kuskokwim delta, had a large, triple pane picture window with an insulated door that swung down from the ceiling and had magnetic seals like a refrigerator door.  The house also has 18″ to 24″ of insulation in the walls and floor (double framed) and more in the ceiling.  We had to insulate the house from the tundra underneath too, to keep the tundra from thawing in summer.  That was an interesting project, but now I have digressed.


4 thoughts on “My Appliances are in Heat

  1. Lyle:

    There was an interesting study done in Canada by BC Hydro. Summarized in a news article, this ended up with:

    “But in cold-weather climates such as Canada’s, Blunden said older incandescent bulbs do more than just light our homes. During the long winter months, they also generate heat. The new CFL bulbs on the other hand produce minimal heat so the loss has to be made up by fossil-fuel burning gas, oil or wood to heat your home. “To some extent, the case [in favour of CFL bulbs] has been oversold” because of the offset in higher heating costs, he said. In fact, a recent report by BC Hydro estimates new lighting regulations will increase annual greenhouse gas emissions in British Columbia by 45,000 tonnes annually as consumers use more energy to heat their homes after switching to more energy efficient — but cooler — lighting.”

    Here in Minnesnowta we have about the same effect. The ONLY heat in our basement is “waste” heat from the furnace enclosure (hot-water boiler feeding the radiators upstairs), radiator piping (asbestos insulated), hot water heater shell, and the dozen-or-so incandescent bulbs. When we installed the new furnace (after the old originall-coal-fired, converted to natural-gas furnace died after 102 years of service) we were required to install a make-up air source. When the furnace is running icy air from outside is dumped into a bucket on the floor to provide combustion air. Without the lights on, that basement gets cold. And since that’s the floor surface of our main living space, the first floor stays cold. Changing those lights to CFL’s would increase our energy costs since we’d just be burning that much more natural gas.

    Another factor is that in the summer-time it’s not necessary to have nearly as much artificial light. It stays light in the sky during the non-heating season to the point where it’s rare to turn on a light in the house. So the fact that an incandescent bulb produces about 5% light and 95% heat isn’t a big factor in the summertime. They simply don’t get used much.

    The AGW hoax was nonsense from the beginning, and the recent divulging of their conspiracy-oriented e-mails, documents and computer files (to refuse to allow contradictory publications in peer-reviewed journals, to secretly alter data through blatantly false “fudge factors” and to deny access to and then destroy actual data) has only confirmed what many people already knew. So I don’t give a rat’s a$$ about “carbon footprint”, or other BS. I’m simply interested in increasing efficiency and reducing costs in an effective manner.

    In general, CFL’s are a net increaser of energy use in geographic locations where there is a majority of time that heating is required.

  2. As a poor student in Montreal I really hated to use the clothes-dryer and watch all of that heat get blown out into the outdoors. But of course venting to indoors caused the paint to peel off the walls.
    My second attempt was a long 4″-dia. polythene tube made with duct-tape and 6-mil plastic. The dryer duct hose connected to the poly tube, and after running into the adjacent room and along the wall under the window it turned back on itself and exited through the dryer vent to the outdoors.
    Just this simple method recovered quite a lot of heat, but it also condensed enough water in a single dryer cycle to completely block the tube at any inevitable low point.
    In the intervening decade and a half, I’ve put some thought into the matter, and still haven’t come up with the ideal D.I.Y. Dryer-vent heat exchanger/heat recovery device from cheap and free scavenged materials.
    It would need an easily cleaned lint-filter, would need to self-drain any condensation to an easily removed container, and use the dryer outlet and vent to the outside at their existing heights. A “winter/summer” baffle lever would be a plus, so that it can remain in place. It seems to me that much of the space normally required behind a dryer just to keep the vent-hose from kinking would be adequate for the heat exchange if the indoor-air could be fan assisted and then perhaps ducted to the living-area where it is of most use.

  3. Blackwing; You could pipe combustion air directly into the furnace, without having it mingle with the air in the living space. Any good combustion heater works that way. Your cost from using cooler light bulbs might increase or it might decrease, depending on the relative prices of the various energy sources involved. The actual net energy use in joules or BTU or whatever, is virtually unchanged, so long as the system is all inside the living space.

    Douglas; An air-to-air heat exchanger that runs the hot and cold sides in opposite directions can achieve amazing efficiency. The problem, as you noted, is dealing with the condensation in cold weather, which could freeze in a highly efficient system. Keeping the condensation in liquid state would require some extra waste, but draining it off is a problem that was solved in air conditioning systems a long time ago. When I lived alone I simply vented the dryer directly into the living space, through a lint filter, in winter. Home heating often results in very dry air anyway, so the extra humidity was OK being as I was the only one there washing clothes.

    And yes– it’s common for any longish dryer vent to fill with water if it’s not arranged as a continual downward slope. I’ve seen it, even without the more tortuous path you describe.

  4. Hmm. Are we thinking too far “inside the box” with this dryer business? If you have an extremely efficient air-to-air heat exchanger, you can dump most if not all the exaust air back into the heated space and still condense most of the water, with no chance of frosting, since you’d be cooling the exhaust to near room temperature. If you were to pressurize it at the and, thereby heating it slightly to wring out more heat, it could actually exit into the room at below room temp, causing it to give up more of the water vapor beforehand. That’s pretty much how jet-liner air conditioning works, BTW, except of course that the heat is rejected to the outside.

    We’ll call our new dryer a “condensing dryer”. It’ll save about 800 million times more energy (give or take) than a stupid CF bulb.

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