Mr. Electricity is your guide to saving energy in your home.
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Battery
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Which battery is best? We cover
rechargeable and alkaline batteries to show you what's hot,
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The
Military Budget as Cookies
This excellent animation from TrueMajority shows in
graphic detail (using Oreo cookies) how ridiculously, large
the military budget is, and how we could solve many domestic
problems with a modest 12% cut. A must-see. (watch
it now)
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How to save money on
refrigerator
costs
Refrigerator energy
use
In most homes the refrigerator is the
second-largest user of electricity (13.7%), right
after the air conditioner (16%).
(Dept.
of Energy) With
most appliances you save energy by using them less,
but you can't very well do that with your fridge.
The main way to save money with your fridge is to
use an efficient model. New fridges aren't just a
little more efficient, they're incredibly
more efficient. A 1986-era fridge uses 1400 kWh a
year, while a post-2001 fridge uses only 500 kWh --
a 64% savings. And the most efficient
fridges use as little as 200 kWh.
Here are some sample yearly costs to run various
fridge, based on the U.S.
average price for electricity of
10¢/kWh:
- $140 - Old 1976-86 fridge
(1400 kWh/yr.)
- $50 - Post-2001 fridge
(500 kWh/yr.)
- $43 - Post-2001 Energy Star
fridge (425
kWh/yr.)
Should you get a new
fridge?
The big question is, Should you replace your
current fridge with a newer, more efficient model?
If your fridge was made before 2001, then yes,
you should probably trade it in. If it's 2001 or
later, it's probably better to hold onto it until
it needs replacing. If you're satisfied with
that answer you can stop here and go onto the
next section, Choosing a New
Fridge. But if you want a more detailed answer,
then let's get started on the math.
First let's take a look at typical electrical
savings by upgrading to a new, efficient fridge
based on what year your existing fridge was made.
The U.S. government gives the EnergyStar
label that use 15% less energy than required by
law, and we'll assume this is the kind of fridge
you upgrade to. (425 kWh/year)
A fridge made
in this year...
|
Uses
about this
much energy...
|
And replacing it
with an Energy
Star model
saves about...
|
|
<1976
|
1800
kWh
|
$151 / yr.
|
|
1976-86
|
1400
kWh
|
$107 / yr.
|
|
1987-89
|
950
kWh
|
$58 / yr.
|
|
1990-92
|
900
kWh
|
$52 / yr.
|
|
1993-00
|
700
kWh
|
$30 / yr.
|
|
2001+
|
500
kWh
|
$8 / yr.
|
|
Assumes
electricity rate of $0.11 per kWh
kWh source: EcoMall.
1976 & 1987 are California
regulations; U.S.
federal
standards
started in 1990
|
So now we're ready to figure out whether it
makes sense to replace our current fridge.
1. Find the annual cost of your current
fridge.
If you no longer have the paperwork
that came with your fridge then call the
manufacturer, or use a watt-meter
to measure the energy use. (Let it run for about
a week to get a good sample.) Figure your annual
cost. For example, if your fridge uses 800
kWh/yr. and you're paying 11¢/kWh, then
you're paying $88/yr. to run it.
If you're too lazy to find out how much
energy your fridge actually uses, you can skip
this step and the next one and use the savings
numbers in the table above to get a rough
estimate of your savings per year from the new
fridge.
2. Find the annual costs of the fridge you'd
like to buy.
The annual kWh usage of the new fridge
is printed on the yellow label on the fridge.
Even if you shop online you'll still see the kWh
per year listed. Once you know the annual kWh,
multiply it by the amount you pay for
electricity. For example, if the fridge you'd
like to buy uses 425 kWh a year and you pay
11¢ kWh, then it'll cost you 425 x $0.11 =
$46.75/yr. to run this fridge, which we'll round
up to $47/yr.
3. Figure the annual savings.
If you measured your fridge's
electrical usage (good for you), just take the
old fridge's cost minus the new fridge's cost to
find the savings. If you didn't measure your
fridge's usage, then use the table above. For
example., let's say you're using a fridge made
in 2000. From the table above you can see that
the newer fridge costs $30/yr. less to
run than the old one.
3. Decide whether it's worth it.
Let's say your new fridge costs $448.
Using the $30/yr. savings from our previous
example, that looks like a payback time of $448
/ 30 = 15 years, but actually that's not the
right way to look at it. First of all, you'd
have to buy a new fridge eventually anyway, so
it's not like the cost of the new fridge is an
out-of-the-blue expense that you'd never have
otherwise. Second, the price of electricity will
probably go up each year, while your cost to buy
the fridge never changes once you buy it. So
let's continue...
Since the useful life of a fridge is only
around 14 years, you're going to have to replace
it sooner or later anyway. So the question isn't
really, "Should I replace my fridge?", but
rather, "Should I replace it early
(before it needs replacing?" Let's say
we're replacing a 9-year-old fridge, so we're
replacing it 5 years early. In that 5 years we
expect to save $30/yr. x 5 years = $150. If we
took our $448 and instead of buying a fridge we
invested it somewhere with a 6% return, our
return after five years would be $152 ($448 x
1.065 = $600). That's practically the
same as what we'd get from replacing the fridge
early, so we might as well replace the fridge.
But in fact it gets better: Any money you earn
on investments is taxable, while money you save
on electricity is not, so in fact replacing the
fridge turns out to be a better deal.
In fact, it's even better than that. In five
years you can expect that $448 fridge to cost
$507 if the inflation rate is 2.5%. So by buying
now you save even more.
And of course, one reason to replace the
fridge now is that saving energy reduces
pollution. I always pay a little more if it
means I pollute a little less.
Help
in choosing a new
fridge
|
Newer models use less
energy. The table at the top of the page
shows the dramatic difference in energy usage for
new vs. old fridges. The actual standard varies
from fridge to fridge, because it depends on the
exact size of the fridge in cubic feet. So a 21.7
ft.3 fridge will have a slightly
different limit than a 20.6 ft.3 fridge.
The numbers in my list above are both approximate
and rounded. Modern fridges are more efficient
because they have better insulation and more
efficient compressors. There is no better way to
save on energy use of fridges than by trading an
old model for a newer one.
Get an EnergyStar
model. The U.S. government identifies
very efficient appliances with an Energy
Star label. As of January 1, 2004,
refrigerators that exceed the federal standard by
15% or more (and full-size freezers that exceed it
by 10%) qualify as EnergyStar appliances. (Between
2001 and 2004, fridges had to be only 10% better
than the federal standard to get the EnergyStar
label.) A typical modern full-size EnergyStar
fridge with a top-mounted freezer uses about 432
kWh/yr. vs. 510 kWh/yr. for a non-EnergyStar model.
If you want to save the most money possible, when
you replace your fridge, replace it with an
EnergyStar model. The extra energy savings should
outweigh the extra cost over the life of the
fridge.
Consumer Reports found that the most
efficient refrigerator they tested used an
average of 64 watts/hr. while the least
efficient used two-thirds more: 107 watts/hr.
The efficient model cost $180 more ($780
compared to $600), but the
energy savings over the 14-year life of the
units was $434, based on the national
average cost of electricity of 8.3¢/kWh.
(1998)
Get a top-freezer
model. Side-by-side models use about 55%
more energy than those with the freezer on top.
Bottom freezers are also less efficient than top
freezers. (source: Cursory
observation of EnergyStar
tables)
An August 2002 Consumer Reports article showed
the following:
- Side by Side, 680 kWh/yr.
- Bottom Freezer; 522kWh/yr.
- Top Freezer, 468 kWh/yr.
Skip the ice maker and
dispenser. Automatic icemakers
and through-the-door dispensers increase energy use
by 14-20% (and the purchase price by $75-250).
(source)
Super-Efficient
Fridges. Sun
Frost makes super-efficient fridges, including
a 16 cubic foot model that uses only 281 kWh a year
in a 70°F environment. They're marketed
towards people who are powering their homes with
solar electricity, where every watt counts. I don't
know how their 281 kWh @ 70° compares to the
other kwH ratings on this page, because I've been
unable to find what ambient air temperature fridge
manufacturers or the EPA use when doing their
fridge ratings. If any reader knows, please
let me know!
But back to listing more super-efficient
fridges: A new Japanese model called CoolView
claims to reduce costs by up to 55%. Also, you can
make your own super-efficient
fridge by converting a chest freezer.
Old manual defrost
fridges won't save
money. You
might have heard that manual defrost fridges use
less energy than frost-free, so you might be
tempted to look for an old manual defrost model.
Don't. Old fridges use way more energy than
new ones, even if the old one is manual defrost. I
once had an old manual-defrost model that used 1000
kWh year, which is more than twice what a modern
425 kWh modern Energy Star, frost-free model
uses.
Now, a modern frost-free fridge is an
energy-saver, but they're hard to find and rather
expensive. The only model I know of is the
ConServ
by Versafrost, which uses 256 kWh at an ambient air
temperature of 68°F. I can't compare this to
the kWh rating for the other fridges on this page
since I've been unable to find what ambient air
temperature fridge manufacturers or the EPA use
when doing their fridge ratings. If any reader
knows, please let me
know!
Saving
energy with your existing
fridge
|
Turn off the
anti-sweat feature.
Many fridges have small heaters that
keep moisture from forming on the cabinet. This
uses an extra 5-10% extra electricity. Most
models that have this feature have a switch that
lets you turn it off, usually labeled "Energy
Saver". source
1 source
2
Set the temperature
for only as cold as you need it.
Fridge should be 36-40F, and the
freezer should be 0-5F (-17 to -10C). Fridges
set 10 degrees lower than needed (or freezers
set 5 degrees lower than needed) can increase
energy use by as much as 20-25%. Personally, I
set my own fridge to 56° because as a
vegan
I never store super-perishables like meat or
dairy.
To test the fridge temperature, put a
thermometer in a glass of water in the center of
the fridge and leave it there for 24 hours. To
test the freezer temperature, put the
thermometer between two frozen packages. If the
temperature is colder than needed, then set the
fridge to a warmer temperature. (source)
Don't put hot foods in
the fridge.
Food safety experts say you should
refrigerate hot food to prevent contamination.
But that doesn't mean you have to refrigerate
them immediately. The USDA
says to refrigerate within two hours of
preparation (or one hour if the room temp is
above 90°). One to two hours of cooling off
time will definitely make your refrigerator work
less. It's a tradeoff -- the sooner you
refrigerate the safer the food, but the more
energy you use. Of course, meat and dairy foods
are most susceptible to contamination, which is
yet another reason to not eat meat and dairy in
the first place. Vegan
foods are much safer.
Yosh Hash sent in the tip that you can
greatly cool items by putting them in a
container and soaking them in a pot of cold
water for 15-30 minutes, which reduces the
amount of heat the fridge will have to remove
once you stick them in the fridge.
Along the same lines, he writes: "A lot of
people do not seem to understand that the middle
position on a faucet means half cold, half
hot. I've seen people fill a pitcher with
lukewarm water and put it in the fridge!
What a waste -- they paid to heat the water,
then they pay to take that heat right back out
of the water. Please tell your readers when when
they're refrigerating water, they should draw
cold water into the pitcher, not warm." Consider
your wish granted.
Thaw frozen foods in
the fridge rather than on the
counter.
They'll help cool the fridge as they
defrost.
Pick a good spot for
the fridge.
Your fridge will use less energy if you
keep it away from heat and also place it where
the heat it generates can easily dissipate.
Position your fridge out of direct sunlight, and
away from heat sources such as the oven and heat
registers. Help the fridge get rid of the heat
it generates by placing it along an external
wall. If you don't use air conditioning then put
the fridge in front of an open window to let the
heat easily escape. This doesn't just make your
fridge work less, it keeps your house cooler
too. If your choices for locating your fridge
are limited then at the very least make sure
there as at least 2" of space all around to
allow for circulation.
More on temperature & energy use:
A Sun Frost fridge uses 61%
more energy in a 90-degree F environment
than a 70-degree environment. Home Energy
magazine has a chart showing refrigerator
energy use per degree of temperature. But
this doesn't mean you should keep your house
extra cool so that the fridge uses less energy,
because you'll use way more energy to cool your
home than you'll save be having your fridge work
less. Air conditioning uses way more electricity
than fridges. Instead, just put your fridge in a
good location, as explained above.
Door
Openings.
Home
Energy magazine says door openings account
for 7% of fridge energy use, assuming 42 door
openings a day. But the Institute
of Food & Agricultural Sciences at the
University of Florida says poor open/close
habits waste 50 to 120kWh a year, which would be
10-24% of a 500 kWh/yr. fridge. They don't say
whether this is too-frequent opening, or leaving
open too long when opening, or both. I'm
openly calling on readers to test how much
door-openings matter, using a Kill-A-Watt
meter, keeping track of how many
times and for how long you open the door,
compared to a 24- or 48-hour period where you
don't open the door at all. Report your
findings and I'll share them with everyone on
this page.
Defrost a
non-frost-free freezer before the frost exceeds a
quarter-inch thick.
More frost makes the freezer work
harder. But better yet, if your fridge isn't
frost-free, that means it's old, and old fridges
use tons of energy. Replace it with a newer
model, made in 2001 or later.
Cleaning the coils
helps a little, but maybe not much.
Just about every other Saving Energy
guide out there (including an older version of
ours) tells you that cleaning the coils on your
fridge is important to saving energy. They're
guessing. I was able to dig up references to a
couple of studies on the matter which showed
that the savings is weak to non-existent --
maybe 5% if you're lucky.
(source,
2nd
link) Now, it
certainly can't hurt to clean the coils,
but don't expect a big windfall. In any event,
I'm openly calling on my readers to test
this. Measure your uncleaned fridge for a
few days with a Kill-A-Watt
meter, then clean the coils and measure it
again. Share your results with me and I'll post
them here.
Here's how to clean your coils: The coils are
the small, winding black pipe either on the back
of the fridge, or the slotted vents on the
bottom. If the coils are clogged with dust the
fridge will use a little more energy because it
can't radiate the heat away as well as it could
with clean coils. Clean the coils with a wire
brush and/or vacuum them with a hand vacuum.
Use a transparent
plastic curtain?
You may have seen these in the
perishables section of a grocery store --
vertical transparent plastic strips. They keep
the cold in while still allowing you to see
what's behind them. The only problem -- the only
material I could find is made from PVC,
which is toxic and something you definitely
don't want in your refrigerator. But And even if
you don't mind poisoning yourself, the only
source I could find was this
bulk roll for $98.95. Seems like a cheaper
solution would be to buy a transparent shower
curtain (also made from PVC) and cut it into
strips. Anyway, if any reader can tell me where
to get transparent, non-PVC plastic (if there is
such a thing) to use as a fridge curtain, be
sure to let me
know.
Make sure the gasket
is in good shape.
The gasket is that piece of rubber
going around the door that seals the door to the
refrigerator. If it doesn't seal well, then cold
air is escaping so your fridge is working a lot
harder. If parts of it are coming off, then
re-attach it with some adhesive caulk.
Turn the fridge
OFF?!
Elizabeth Stone writes:
"I was inspired this month
to unplug my refrigerator and cool just with ice
that I can make outdoors. I can keep the
refrigerator at 45 degrees for about five days
with a couple of big pot fulls of ice. It had
occurred to me how wasteful it was to be cooling
something in the winter in a northern climate!
It takes more attention and effort than just
having a plugged-in refrigerator, but perhaps
there are others out there that might also try
this if they were given the idea."
That's an excellent tip! Notice you don't
even have to turn the fridge off: You can keep
the fridge on but the compressor won't kick in
anyway because the inside temperature is already
cold enough. Then when the ice melts and starts
losing its effect, the compressor will kick in
automatically, and you won't have to worry about
your food spoiling. That way you don't have to
remember (or guess when) to turn the fridge back
on.
Data on old
fridges.
The California Energy Commission
compiled a massive database
of energy use for 41,000 different
refrigerator models from 1979 to 1992.
Convert
a chest freezer into a super-efficient
fridge
|
Tom Chalko in Australia has figured out a way
to make a super-efficient refrigerator that uses a
mere 0.1 kWh a day, or 36.5 kWh a year! The
trick is to just use a chest freezer as a fridge,
after installing a new thermometer to turn the
freezer off when the temperature drops too low.
Chest freezers are more efficient than fridges
because they have more insulation and because the
cold air doesn't spill out when you open the door,
because cold air falls down, not up.
There are a couple of obvious downsides. First
is that it might not be as easy for you to access
your food in a chest freezer. Another is that the
new fridge will take up more floor space. Finally,
you'll need a separate freezer. But if things
things don't put you off, then you can save quite a
bit of energy. Read Tom's instructions for
how
to make a super-efficient fridge.
Below are questions I've received and
answered about saving on refrigerator energy
costs.
|
Ask
Mr. Electricity about saving refrigerator
energy
I think we can help the
coils get rid of heat better by spritzing them with
water when the motor is running and the coils are
very hot. I can tell it works because of the
steam that comes off and because the motor shuts
off quicker. (Yes, i know it opens up a
wealth of issues, like the danger of electrocuting
yourself if you have bad wiring, or eventually
building up sediment from hard water, so of course
all this has to be underscored with common sense.)
I am simply stating that there is a lot we can do
to help coils get rid of heat.
-- Yosh Hash,
July 2008
I'm always happy when readers come up
with creative ways to save energy. Yes, you're
right, this will help your fridge get rid of
heat faster. However, if you're also
air-conditioning your home, then your AC will
ultimately be removing the same amount of heat
anyway (just over a different period of time) so
I wouldn't expect to see any overall savings if
you've got the AC going. But if you don't
air-condition your kitchen, like me, then
there's a potential for savings. How much? It
depends on how often you spray your coils and
what the humidity level is in your environment.
I'm openly calling on readers to test this
theory with a Kill-A-Watt
meter and report their results,
which I'll share here. Measure your fridge
for a few days normally, then measure it again
for a few days where you're periodically
spraying the coils, noting how often you do so.
I don't know why the
manufactures don't make a detachable unit so that
the coil can be put somewhere cool while the fridge
itself stays in the kitchen.
-- Yosh Hash, July
2008
It's a good idea, but fridge-makers
won't do this because selling only two units (to
you and to me) probably wouldn't be profitable.
Consumers want the convenience of a single unit
without any other external parts.
The beauty of your idea is not just that you
could put the condensing unit somewhere cooler:
If you could put the condensing unit
outside (just like you do with a central
AC system), then you wouldn't constantly be
adding heat to your kitchen which you then pay
to remove with your air conditioning.
I don't think any commercially-available
fridge exists with a detachable condensing unit,
but if any reader knows of one, then by all
means please let me
know.
How many hours a day
does the compressor in the fridge run, on average?
-- Spiney
Norman, June 2008
Interesting question. My fridge uses
143 watts when the compressor runs and 0 watts
when it doesn't. From the table above, a modern
fridge uses about 500 kWh a year. On a daily
basis that's 500 kWh / 365.25 days = 1.37 kWh a
day, or 1370 watt-hours. 1370 Wh / 143 W =
9.6 hours/day. Of course, if you don't
heat or cool your home much like me then it will
run more in the summer and less in the winter,
but this is a pretty good estimate.
What is this number useful for? Well, say you
wanted to compare the cost of leaving the door
of your fridge open all the time to something
else, like I do on the cooling
page. For that you'd need to know how many extra
hours a day the compressor runs (which we've
calculated to be 24 - 9.6 = 14.4 hours), or at
least what percentage of time the compressor
runs (which would be 9.6 / 24 = 40%).
I live in a house with
four other people. Recently they've been eating my
food. I was thinking about putting my food in a
metal box with a lock on it (extreme I know). A
friend told me that I shouldn't do this because it
would require more energy for the fridge to cool
down. But that doesn't seem right to me. Metal
cools very easily and stays cool very easily, so it
would seem to me that besides being a little
annoying it shouldnt be a problem. Who is right?
-- Lee-Ana,
Santa Cruz, CA, Jan. 2005
That's really funny. Reminds me when I
was in college and a housemate would spit in his
Kool-Aid so nobody else would drink it.
To answer your question: you're right, your
friend is wrong. What refrigerators do is to
extract heat from things. Technically they don't
insert coldness, what they do is to suck out the
heat. When you put a bunch of your
room-temperature groceries in your fridge the
fridge starts sucking the heat of them and
sending that heat to the coils on the back or
the bottom of the fridge. It takes the heat
that's on the inside and sends it to the
outside.
Putting a room-temperature metal box in the
fridge is no different from putting a
room-temperature bag of carrots in the fridge.
The fridge is gonna suck the heat out of both
objects and send it to the outside of the
fridge. Once either object has had its heat
removed it doesn't take any extra energy to keep
it cool, because its heat has already been
extracted. When the fridge runs after it's
cooled the contents, it's because of heat
entering the fridge from the outside (slowly
seeping through the walls of the fridge, or
through the door when you open it.) Hope this
helps.
I am looking to
purchase a new refrigerator and cannot find out how
many watts of power it uses. It has an Energy
Star rating with a high and a low rating in
kWh/year from 618 to 727 according to
its
Energy Star
tag. How do
I find out from the Energy Star tag how many watts
it uses? Should I guess that it means 618 to
727 watts?--
David, Dec. 2004
What you're looking for is really right
there on the label. The label does not
say that the fridge has a high and low rating in
kWh/year of 618 to 727. What it actually says,
in large, bold, reverse type, is "Energy use
(kWh/year) range of all similar models."
This means the most efficient competing fridge
in the same class as the one you want to buy
uses 618 kWh year, while the least efficient
uses 727.
The model you're looking at uses 607
kWh/year. I know this because it says so right
on the label (in large, bold type, right above
the range listed above). This fridge is
therefore the most efficient one in its class
that you can buy since it uses less than similar
models. Of course you've chosen the least
efficient style -- as mentioned above,
side-by-side models use more energy than either
top-freezer or bottom-freezer models.
If you want to know how many watts the fridge
uses while the compressor is running, you can't
find that from the Energy Star label (you'd have
to look at the fridge itself), but then again
I'm not sure why you'd want to since that
information is fairly useless. The label tells
you the kWh/yr., and how many kWh/yr.
other fridges use. That's what you need
to know.
I have a 12v fridge
which uses 3.5 amps when running, or 42 watts. This
seems like a fraction of what my 240v small fridge
downstairs uses. Factoring in the inefficiency of
my 4amp rectifier at say 70%, it seems that the 12V
fridge uses less power than the 240v fridge. Is
that right?--
Paul O'Kane, Brisbane, Australia, Dec.
2004
Well, you didn't tell me how much power
your 240V fridge uses, in either amps or watts,
so it's kind of hard to compare. I also don't
know how big each fridge is, or how old each one
is. You haven't given me much to go on. You
could easily measure
the electrical use of each unit to get a good
and accurate comparison yourself. You have
access to the equipment, but me sitting over
here on the other side of the planet without
even a good idea of what kind of equipment
you're running, I'm just guessing. But as long
as I'm guessing, let me guess that the key here
is that the 12v fridge uses less power when
running, but that it has to run longer to
chill an equivalent amount of space compared to
the 240V fridge.
Can I save energy by
putting my refrigerator or freezer outside in the
winter? --
Marty Siller, Oct. 2004
You can put your freezer outside
as long as the temperature is usually above 0
degrees F. You can't put your fridge
outside, though. Well, you can, but your food
will spoil.
When the ambient temperature is too low your
fridge gets confused and so it doesn't run the
compressor as long as it should. That means that
the temperature inside the fridge winds
up being too warm. A General Electric manual I
just checked said not to run the fridge when the
ambient temperature is below 60 degrees F.
Freezers are more forgiving, since they cool
to a lower temperature. A GE freezer manual says
that the freezer will work fine with ambient
temperatures as low as 0 degrees F.
Appliances vary, so check your own owner's
manual to see what your equipment's temperature
tolerance is before you try this.
In order to save
electricity, is it safe to turn off the
refrigerator/freezer before going to bed and
turning them back on in the morning? I would like
to know if doing this may damage the appliance.
-- P.M.
Vasquez, May 2004
This won't save any electricity. As
soon as you turn the fridge back on, it will run
a bit longer to get the temperature back down to
normal. If you turn the fridge off at night then
you might keep the compressor running for 60
minutes throughout the night, over several
start-stop sessions, but when you turn it on
again then it will simply run for 60 minutes all
at once.
Careful readers have wondered why this
contradicts my advice for air
conditioners, where I say that it uses more
energy to keep the AC on during the day than to
just turn it on when you get home. They question
why my fridge answer wouldn't work the same for
the house: aren't we just delaying the
heat-removal process until later, rather than
reducing it?
It's a good question, and here's why it's
different: A constantly-cooled fridge
(overnight, with the door closed) is just not
the same kind of heat magnet that a
constantly-cooled house is. The whole fridge is
sealed and insulated and is sitting in a house
that's probably itself air-conditioned down to
80° or lower. So constantly cooling the
fridge doesn't let appreciably more heat enter
than turning it off overnight and having it
remove the accumulated heat in the morning.
Of course, this is just theory, so I plan to
test this soon and report the results. In the
meantime, I hope readers will do their own tests
with a Kill-A-Watt
meter, running the fridge for a few nights
normally and then running it for a few nights
with it off at night and then share
the results with me.
My boyfriend believes
that if we keep several jugs of water in the
freezer and in the refrigerator that it will keep
the cost of electric down.... Does this really
work? -- Angie
Stanton, Feb. 2004
Sheesh, boyfriends will believe
anything. Okay, technically the answer is "it
depends", but for all practical purposes the
answer is "no".
When you open the fridge cold air gets out
and warm air gets in. If your fridge is full of
water jugs then there's less room for warm air
to rush in and occupy, so your fridge can cool
back down to the proper temperature quicker. But
a fridge full of food serves the same
purpose, and most people's fridges are already
pretty full. The only way adding water jugs
would save much energy would be if your fridge
is usually fairly empty and you open the door
frequently -- but if the fridge doesn't have
much food in it then why would you be opening
the door so much? So the bottom line is, it's
not really going to make an appreciable
difference.
By the way, when you're ready to upgrade to a
boyfriend who knows about refrigerators then
drop me a line again.
This page last modified
September 2008.
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