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Q:
Do you really need to turn off unused lights in
winter if you have electruc heat in your house?
I mean suppose that you close the shades so
that no light goes outside. Then, doesn’t all
the electrucal energy you use wind up as heat anyway.
Actually, anything electrucal.... just leave them
all on... whether the thing is efficient or not, doesn’t all the energy it uses wind up as heat in your house eventually.
What’s up with this?
And it seems like this is still mostly true
even if you have some other kind of heat in
your house... except for the fact that gas-heat
is sort-of cheaper than electruc
- Chris Leo III
A:
Chris,
You are right that most of the energy that goes into a light
bulb will end up as heat somewhere in your house, but the key question
is "where" that heat ends up.
If you feel the light bulb and
the fixture that holds it you will certainly notice that it gets hot.
The problem is that this is not necessarily doing much to heat the rest
of the house. For example, if your light fixture is in the ceiling,
heating the fixture will not do much to heat the air in the room since
heat rises and the warmth generated by the light will tend to stay in
(or near) the ceiling. Even a table lamp wont heat you very efficiently
since it is not designed for the primary purpose of transferring heat
to its surroundings (although it would be somewhat better than a
ceiling light).
The bottom line is that you are better off
turning off the light bulb and using the electricity you save to run a
real heater which is carefully engineered to warm the air in the room.
MS
(published on 10/22/2007)
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