Mr. Electricity is your guide to saving energy in your home.
We're recommended by the government of Berks County, PA.
Related sites:
Watt Watt. News about efficiency and conservation, written by readers of the site.
Home Power Magazine. All about renewable energy for the home.
Thin House. Blog about a family committed to cutting its energy use by 80%.
No-Impact Man. Blog about a family striving to have no net impact. (i.e., What little they use, they offset.) Inspirational.
Off-Grid. News and resources about living without being connected to a utility company.
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If you like this site, you might also like some of my
other sites:
Battery
Guide
Which battery is best? We cover
rechargeable and alkaline batteries to show you what's hot,
what's not, and the best way to charge them. (visit
now)
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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 the
use of washing machines (clothes
washers)
Cost per load
(top-loader)
A washing machine uses about 0.256
kWh per load. At the national
average of 11¢/kWh, that's $0.03 per
load for electricity. The machine also uses
about 40 gallons of water. At a national average
of $2.81 per thousand gallons, that's $0.11. So
our costs for electrical and water are
$0.03+$0.11 = $0.14, before we consider the cost
to heat the water, which we'll do now. The table
below includes the $0.14 cost of base
electricity + water.
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Total
cost per load (electricity + water + water
heating)
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Wash / Rinse setting
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Electric water
heater
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Gas water heater
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Hot / Warm
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69¢
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52¢
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Hot / Cold
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50¢
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39¢
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Warm / Warm
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50¢
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39¢
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Warm / Cold
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32¢
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27¢
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Cold / Cold
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14¢
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14¢
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See
how
this was
calculated.
A front-loading washer costs 7¢
to 34¢ per load, depending on water
temperature and heating method.
Your actual cost for all of the above will
be different, according to your actual local
rates for electricity, water, and perhaps gas,
and how much you actually use your washing
machine.
Heating the water is most
of the energy use
A whopping 95% of the energy used by
a washing machine could be going just to heat
the water. So you can save a bundle by just
just lowering the temperature. You could also
get a front-loading machine, which uses about
63% less water than a top-loader (and therefore
spend less to heat the water.)
Here's the cost when your water is heated
with electricity:
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How
water temperature affects the price per
load
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Wash/Rinse Setting
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Electrical Use
kWh/load
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Cost per load
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Cost per year
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Hot / Warm
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5.24
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58¢
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$226
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Hot / Cold
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3.58
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39¢
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$154
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Warm / Warm
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3.58
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39¢
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$154
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Warm / Cold
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1.92
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21¢
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$83
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Cold / Cold
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0.26
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3¢
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$11
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Electrical cost only (excludes
the cost of water, which is 11¢/load.)
See
how
this was
calculated.
-
- To put in perspective how wasteful hot water
is, washing your clothes in hot instead of cold
for a year, uses more electricity than leaving
the refrigerator door open 24 hours a day
for a year.
(Fridge open
24/7: 143 watts x 14.4 extra hours day x 365
days/yr. = 752 kWh.)
- Always use cold water for the RINSE cycle.
Using warm or hot water for the Rinse cycle
doesn't get your clothes any cleaner.
- Try using warm or cold water for the WASH
cycle instead of hot water. Hot water shrinks
your clothes, anyway. Hot water also fades and
wears your clothes out quicker.
- If you feel that warm water doesn't clean as
well for you as hot, then just use a warm
pre-soak. Soaking clothes in warm water is
usually just as good or better as hot water with
no soak.
- Use a centrifuge like the Spin
Dryer which removes most of the water from
washed clothes by spinning them really fast.
That means a lot less time in the dryer, saving
energy.
- Run around the house naked. Then you'll have
less clothes to wash.
- Replace your washer with a front-loading
model, which uses 63% less water on average.
That's our next topic....
Front-loading washing
machines
- Front-loading washers use 40-75% less
water and 30-85% less energy than typical
top-loaders (10 to 24 gallons vs. up to 40
gallons, and 120-560 kWh/yr. vsi. 800 kWh/yr.).
They cost a little more up front (starting
around $700), but they can slash your energy
bill. Some states (such as Oregon)
offer tax credits or rebates for the purchase of
a front-loading washer. In Europe, more
than 90% of washers are
front-loaders.
- Your clothes will also last longer with a
front-loader, because they gently tumble your
clothes instead of jerking them around with an
agitator -- but they still get your clothes just
as clean as a regular washer.
- Front-load washers squeeze more of the water
out of your clothes, so you'll spend less to dry
your clothes.
- Since front-loaders lack the central
agitator, it's easier to wash large items like
bedspreads, rugs, and sleeping bags.
- If you really prefer top-loaders, there are
some Energy
Star models like the $800 EcoWasher
that rival front-loaders for miserly water and
energy use. (Unfortunately, the EPA's list of
Energy Star washers doesn't bother to mention
whether each washer is top-load or front-load.
Who wants to volunteer to look up that
information so I can publish it on this
site?)
- Wikipedia has a good comparison
of top-loaders to front-loaders.
- The question everyone wants to know is,
"Will a front-loading washer pay for itself in
increased savings?" We have the answer to that
question below.
Will a front-loading
washer pay for itself in utility
savings?
Absolutely. The only time it won't is if
you already use cold water almost exclusively,
and you do a lot less than the average eight
loads a week.
I'll show typical costs and savings below, but
you can get a more accurate idea for your
particular situation by using the
EPA's Excel spreadsheet. For now let's use
typical assumptions:
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Front-Loader
vs. Top-Loader, Annual Cost (w/ ELECTRIC
water heater)
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Wash / Rinse setting
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Top-Loader
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Front-Loader
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Yearly Savings
|
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Hot / Warm
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$270
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$133
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+$137
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Hot / Cold
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$196
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$118
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+$78
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Warm / Warm
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$196
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$90
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+$106
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Warm / Cold
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$125
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$74
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+$51
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Cold / Cold
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$55
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$27
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+$28
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Includes
electric +
water + water heating costs. See how
this was
calculated.
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Front-Loader
vs. Top-Loader, Annual Cost (w/ GAS water
heater)
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Wash / Rinse setting
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Top-Loader
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Front-Loader
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Yearly Savings
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Hot / Warm
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$204
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$94
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+$110
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Hot / Cold
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$153
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$90
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+$63
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Warm / Warm
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$153
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$63
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+$90
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Warm / Cold
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$106
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$59
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+$47
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Cold / Cold
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$55
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$27
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+$28
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Includes
electric +
water + water heating costs. See how
this was
calculated.
Front-loaders look to be about $270 more than
top-loaders, from what I saw at Sears.com in
Oct. 2008. If you save $75/yr. with your new
front-loader, it will take less than four years to
pay for itself. Of course, if you can sell your old
washer for anything, then the payback time is even
quicker. You can also accelerate the payback time
if your local utility or state (such as Oregon)
offers a rebate program.
Remember the other advantages to a
front-loader, including gentler washing action
which makes your clothes last longer (even though
they still get just as clean), the ability to wash
larger items such as blankets and bedspreads, and
the fact that they squeeze more water out of your
clothes so it takes less time and money to dry
them.
Remember also that energy costs could
increase! Many experts are predicting a surge
in the cost of electricity and natural gas over the
next decade. If that happens, your savings could be
even more dramatic.
If you're wary of upgrading, then remember
that you can save up to $215 a year from simply
switching from hot water to cold water, without
having to trade in your washer.
EnergyStar
washers
The EPA awards an Energy Star logo
to washing machines with a minimum
better-than-average efficiency. (Don't
confuse this with the Energy Guide label,
which appears on all washers.) Most
front-loaders qualify for the Energy Star
designation, and most top-loaders don't.
Here's the EPA's list
of Energy Star washers -- though helpfully,
they don't bother to list which ones are
front-loaders and which are top-loaders. You can
download an
Excel spreadsheet from the EPA's washing
machine page if you'd like to sort the
columns.
Washing machine energy
use
The energy use of washing machines
varies a lot depending on:
- the model
- the size (capacity)
- the water temperature used
The government's Energy Guide labels
include the energy required to heat the water,
but they don't make that clear on the label,
which results in a lot of confusion. For
example, one
unsuspecting consumer's blog post
made the mistake of counting the energy used for
heating the water twice, because she didn't know
that the figure she found for the machine's
energy use already included the energy to heat
the water.
A typical top-loading washing machine uses
about 0.26 kWh per load. I haven't been able to
find any good figures for front-loaders, but I
believe them to be about the same as top-loaders
for just the machine's mechanical action, and so
that's the figure I used in my calculations for
this page.
You can see more figures for washing machine
energy use in my sources.
Shame on washing machine
manufacturers for not publishing specs
No U.S. washing machine manufacturer
bothers to publish energy and water use per load
specs in their user manuals or on their
websites. The sites generally do have a
"Specifications" listing, and sometimes even a
"Detailed Specifications" listing, but somehow
they don't consider the amount of electricity
or water used to be a relevant specification
of a washing machine! These ridiculous omissions
are unfair to consumers -- and for me, it means
it took several extra hours to compile the data
for this page trying to hunt down good figures.
Every single American manufacturer I
checked out failed to publish propers specs.
Those manufacturers are:
- General Electric (GE)
- Frigidaire
- Kenmore (Don't know for
sure that their manuals don't have proper
specs, since, unlike other manufacturers,
they don't let you download manuals directly
from their site, which is a problem in and of
itself. Instead they force you to go to some
other site, which forces you to register
before you can dowrload. I tried that, but
the registration form was broken, so I was
stuck.)
- Maytag (also, stupid
Flash-based website means it takes forever to
go from page to page)
- Whirlpool (stupid Flash
animation means you have to wait for the home
page to load, and there are too many problems
with their survey form to recount
here)
- Samsung (Cumbersome,
slow, annoying Flash animation on every damn
page. Slowest website of all I tried, and
many of the others were already pretty damn
slow.)
- Speed Queen (A
downloadable marketing brochure does list the
gallons per load. That info isn't on their
website or in their user manual, and kWh and
gallons per cycle can't be found
anywhere.)
- Amana (User manual is a
ridiculous sixteen-megabyte download!
And even with a whopping 16 megabytes of
data, there's no mention of the energy or
water consumed by their product.)
- KitchenAid (Owned by
Whirlpool. EPA says they make some Energy
Star washers, but I couldn't find any washers
at all on their website.)
- Crosley
Most foreign manufacturers whose products are
sold in the U.S. also fail to provide proper
specs:
- Bosch
(Germany)
- Electrolux (Sweden;
"Frigidaire" in the U.S.)
- Fisher & Paykel (New
Zealand)
- Haier (China)
- LG Electronics
(Korea)
The only manufacturer I found which
published any of these necessary specs is
Asko.
Their user manual for their WL6511 model has a
table showing kWh, temperature, and gallons for
each distinct washer program, but it's still
lacking: The model has a built-in water heater,
and doesn't clearly show how much energy the
washer uses if you just use plain tap water
without heating it. In fact, the energy figure
given for the lowest-temperature cycle looks to
be an impossibility, as I explain in the
sources.
Sources
for tables and calculations
General figures
Average
price of electricity ($0.11/kWh). Our
cost
of
electricity
page.
Average price of gas ($1.42/therm).
Dept.
of
Energy,
est. as of Oct. 2008.
Average price of water ($2.81/thousand
gallons). Earth
Times.
kWh to heat a gallon of water by 63°F
(0.166). From my water
heaters
page.
therms to heat a gallon of water by 63°F
(0.0089). From my water
heaters
page.
Loads of laundry per year (392).
EPA.
Top-Loader figures
kWh per
load, machine only (0.256). Modesto
Irrigation
Dist.
An EPA
Excel
Spreadsheet
gives 0.21 and the Multi-Housing
Laundry
Assoc.
gives 0.30 kWh. I'm taking the middle
figure.
Cost of electricity per load (3¢).
11¢/kWh x 0.256 kwh = 3¢.
Gallons per cycle (40). California
Energy
Commission.
MHLA gives 34
gallons.
Cost of water per load (11¢).
$2.81/1000 x 40 / $0.11.
Portion of water in wash vs. rinse cycle
(50/50). EnergyGuide.
Portion of water that's hot, on warm setting
(50%). Wild guess.
Cost of extra electricity per Hot setting
(37¢). 40 gallons x 50% for wash cycle
x 0.166 kWh/gallon x 11¢/kWh.
Cost of extra electricity per Warm setting
(18¢). 40 gallons x 50% for wash cycle
x 50% because only half the water is hot to make
warm water x 0.166 x 11¢/kWh.
Cost of gas per Hot setting ($0.25). 40
gallons x 50% for wash cycle only x 0.0089
therms/gallon x $1.42/therm
Cost of gas per Warm setting ($0.13). 40
gallanso x 50% for wash cycle only x 50% because
only half the water is hot to make warm water x
0.0089 therms/gallon $1.42/therm
Front-Loader figures
Water
savings vs. top-loader (40-75%).
EPA
, excluding small washers (less than 3 cu. ft.)
to be fair.
kWh per load, machine only (0.26). I've
been completely unable to find this information,
so I used the same figure as for a top-loader,
which should be fairly similar, since the real
energy savings from a front-loader is in using
less water and thus using less energy to heat
the water. Not
a single manufacturer of Energy Star washers
in the U.S. bothers to publish how much
electricity its washers use per
cycle.
One that almost does is Asko, whose user manual
for the WL6511 model shows the energy use per
program but unfortunately does not show energy
if you don't have the machine heat the water.
(The unit has a built-in heater.) The program
with the lowest temperature listed is for
86°F, using 0.30 kWh, but the energy
required to heat 11.9 gallons of wash water to
86°F from 56° (a typical tap
temperature) is 0.87 kWh, more than the 0.30 kWh
figure listed in the table, so their table is
unclear. Does the 0.30 kWh figure perhaps refer
to an unheated wash? If so, then why does the
same line show that the water temperature is
86°F? Perhaps the 0.30 kWh is for a
cold-water wash, but that's close enough te
0.26, because the 0.04 kWh difference doesn't
even make half a penny's difference in cost per
load.
Cost ef electricity per load (3¢).
11¢/kWh * 0.26
Gallons per load (14.7). Oct. 2008
spreadsheet downloaded from the EPA's
clothes
washers
page.
Cost of water per load (4¢). 14.7
gallons x $2.81/1000
Gallons per wash cycle (12.2). The
average front-loader uses 14.7 gallons of water
according to the The user manual for the Asko
model referenced above lists 14.3 gallons total
and 2.4 gallons for the Rinse cycle, which would
be 11.9 gallons for the Wash. The Wash is thus
83.2% of the total water. So I figure a typical
front-loader uses 14.7 gallons x 83.2% = 12.2
gallons. From there I apply the kWh and therms
to heat water as per the earlier
sources.
Cost of
extra electricity for Hot wash (23¢).
12.7 gallons x 0.166 kWh/gallon x
11¢/kWh.
Cost of extra electricity for Warm wash
(12¢). 12.7 gallons x only 50% hot x
0.166 kWh/gallon x 11¢/kWh.
Cost of extra electricity for Warm rinse
(4¢). 2 gallons x 50% of water is hot x
0.166 kWh/gallon x 11¢/kWh.
Cost of
gas per Hot wash (16¢). 12.7 gallons x
0.0089 therms/gallon x $1.42/therm.
Cost of gas per Warm wash (8¢). 12.7
gallons x only 50% hot x 0.0089 therms/gallon x
$1.42/therm.
Cost of gas per Warm rinse (1¢). 2
gallons x 50% of water is hot x 0.0089
therms/gallon x $1.42/therm.
Links to related
info
Below are questions I've received and
answered about how saving on the use of laundry
appliances.
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Questions
answered about washing machines
Everyone says to run
appliances like washing machines and dishwashers at
night to save money. Is electricity cheaper at
night?
-- Melissa,
Appomattox, VA, Mar. 2003
Not usually, but it depends on how your
utility company charges you for power.
Some utilities charge less for evening
use, and you can check your electric bill or
call your utility company to find out for sure.
It could also pay to run appliances in the
evening when the air conditioning is off if your
utility company has a demand charge. See
the next answer.
 Does
it raise your electric bill to run two appliances
at the same time rather than one after the other?
Like, say, the washer and the dryer or the oven and
the dryer? We have an all electric house and were
trying to save money on our electric bill.
Christie,
Jan. 2003
It depends on whether your utility
company has a separate demand charge in
addition to the consumption charge. The demand
charge based on the maximum amount of
electricity you draw at any one time. This chart
from Wisconsin
Electric illustrates the concept. The shaded
area is how much electricity you used, and you
know you get charged for that. But the black bar
on top is the demand, how much energy you
"demanded" at any given point throughout the
day. If your utility company has a demand charge
(ask them), then you can save money by spreading
out your electrical use throughout the day.
Running appliances one after the other rather
than at the same time would reduce your demand.
And better yet, running them when you're not
using much electricity for other purposes (such
as at night when the air conditioner is off)
will reduce your demand even more.
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