For years the Federal Energy Star program has perpetuated the myth
that if you buy appliances (or any electrical device) for the home
that uses less energy, you'll see proportional savings in your monthly
power bill. This is rarely the case.

http://www.energystar.gov/index.cfm?c=home.index

Other eco-writers do similar simplistic math to calculate savings in
money, energy and carbon. A recent example is Charles Fishman's
September 2006 article in Fast Company magazine about WalMart's CFL
project, "How Many Lightbulbs Does it Take to Change the World?".

http://www.fastcompany.com/magazine/108/open_lightbulbs.html

The claim is made that if a single light bulb using 45 watts less is
placed in 100 million homes, 6.57 billion Kilo-Watt-Hours will be
saved. The fact is, unless you are cooling your home, there is ZERO
savings. Charles focused on the bulb, but forgot about the home. His
entire premise is based on a false assumption. The savings are grossly
exaggerated.

"Wasted" energy takes the form of heat. And this heat helps heat your
house, if only just a small amount. For most of America, for most of
the year, that 45 watts will be automatically added back in by the
home heating system to maintain the same level of comfort. If the home
is heated with electricity, the savings in dollars, energy and carbon
production is literally ZERO.

The only time energy is actually saved is when the air conditioning is
running or you have the windows open to cool the house. With the air
conditioning on, the savings can even be a little greater than 45
watts, but for most of America that's a small part of the year. What
are the savings for the rest of the year?

ZERO!

If you are not cooling your home, EVERY light bulb and appliance is
100% efficient.

Here's why...

The second law of thermodynamics demonstrates that "wasted" energy
tends to disperse evenly. And if this "wasted" energy is in your
house, it simply keeps you warm. More importantly, it keeps your
normal heat source from turning on. Let's see how it plays out in a
real home and why saving energy by turning off the lights is mostly an
illusion (pardon the pun).

If you have a home in the northern latitudes which is electrically
heated much of the year, you are a net consumer of heat. And the nice
thing about heat is that It doesn't matter where it comes from. And
that's the key.

Take a light bulb that's only 10% efficient. That means 90% of it's
energy is converted directly to heat. So what happens to that heat? It
spreads out through your house and slightly delays your normal heating
system from clicking on.

And what about the 10% of the energy in the form of visible light?
Virtually all of it strikes objects in the house. It too is converted
to heat. The ONLY ineffectiveness of a light bulb in a northern home
in the winter is the light that escapes through the windows, which is
a VERY small amount. Even THAT can be stopped with curtains. Which
would make ANY light bulb 100% effective at producing heat. Here's how
Wiki explains it... Efficiency versus Effectiveness.

http://en.wikipedia.org/wiki/Electrical_efficiency

Why do I qualify this with northern homes and winter? Because if you
have to open the windows to be comfortable, you lose the advantage.
And if you have to turn on the air conditioning, this "effectiveness"
actually becomes a small liability. So those of you in Florida and
south Texas, nevermind.

It's all about heat, where it moves and how we store it. But for most
of America, much of the year, energy efficiency is very much an
illusion. Effectiveness rules the day because we actually USE that
"inefficient" heat.

And if your windows are closed but your heat is NOT turned on? Or not
turned on until later at night? Those appliances are still 100%
effective. That's because they are helping keep the house warm. They
are one reasons your electric heat hasn't come on yet. If that heat
doesn't come from one source, it has to come from another.

But what if you're a bit on the warm side in late afternoon but you
haven't opened the windows? Again, it doesn't matter. This thermal
intertia will delay heating later on. As long as you don't have to
cool your house, everything is 100% effective. Let's take a couple
more examples.

Electric blanket - 100% effective. If you turn it off, the electric
wallboard heating will kick up 100 watts to compensate: net cost of
blanket electricty for the same comfort level - zero.

TV, DVD & computer - Left on all the time? No problem, as long as the
air conditioning doesn't kick on.

Hair dryer - 100% effective (and only used for short periods anyway),
so get every hair in place.

Electric touthbrush - Yep. Even the charger is a perfect machine.

Refrigiator - 100% effective. This is one of my favorites. What does a
refrigiator do? That's right. It compresses gas to pump heat from the
inside to the outside of the ice box. Where does that heat go? It
heats the kitchen! Even the compressor is 100% effective! Once again,
it saves energy that would come from electric heat.

Why do I keep referring to electric heat instead of oil or gas? That's
because in the past gas has been far cheaper than electricity per BTU.
This made electrical devices a little less "effective" (and a little
more expensive) in producing that "wasted" heat. Unfortunately, cheap
gas is history. The price of oil and gas now approachs that of
electricity. There's no big difference. Leaving your TV on is now
almost as cost effective as buying natural gas.

This "effectiveness" creates the strange situation where you could
turn EVERYTHING in the house off (except for the electric heat) and
set in the dark for a winter month with no entertainment or hot food -
and your power bill would be EXACTLY same. Try it sometime. You'll
see.

This also means you could go out and buy the most efficient light
bulbs you could find and all new Energy Star appliances; STLL the
power bill would be EXACTLY same. So enjoy your gadgets and think
twice before spending extra for "efficiency". Spend your money were it
counts.

And where might that be? If there's little advantage to "efficient"
appliances, how can we save energy and money? That's another blog
post, but start by taking a look at the heat leaving your home through
the walls or down the drain as hot water. Those two are your biggest
loses.

Heat and air conditioning use 50% of home energy. Better insulation
and sealing can save up to 25% of your energy cost for the typical
home. But make sure the house still has reasonable ventilation -
especially in radon areas. And hot water is about 13% of your energy
use, so again, use it carefully. It's not effective to heat up the
sewer drains.

Which brings up one important exception to this "effectiveness" rule -
the clothes dryer. It blows it's heat outside and also brings in cold
air - you lose. It's a good reason to get a clothes line. Or use the
dryer sparingly.

There you have it. Now you can sleep better (and warmer) knowing your
heat isn't as "wasted" as you thought.

OK. If you still want to know how much of that 65.7 KWH you would save
by buying that bulb, multiply it by the ratio of cooling days over
days in a year (365.25). The extra air conditioning load will be
offset by less probable need for light in the summer. For me in Reno,
Nevada that extra efficiency can be used about a quarter of the time
(in the summer) which is probably about average for America. This
makes WalMart's claim overstated by four times - you decide if that
bulb still makes sense.

But why would Fast Company, WalMart and Energy Star not point this
out? Simple. It would make the story less exciting, WalMart would sell
fewer light bulbs and... and... I don't know what's wrong with the
Federal government.

So from now on, don't let some slick magazine make you think a new
light bulb will solve all your problems; don't expect WalMart to
always save you money. And finally, don't expect the government to set
them both straight. When you hear about efficiency, think also about
effectiveness.

And quit worrying about your household appliances.

They are almost perfect machines much of the year..

No matter what their efficiency rating.

Posted by Loren Amelang on February 2, 2007, 4:15 pm

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On 2 Feb 2007 12:05:41 -0800, "Sudden Disruption"
...

>Which brings up one important exception to this "effectiveness" rule -

>the clothes dryer. It blows it's heat outside and also brings in cold

>air - you lose. It's a good reason to get a clothes line. Or use the

>dryer sparingly.

Add the clothes washer and the dishwasher. EnergyStar attempts to
include the energy used to heat the water they consume, much of which
goes down the drain and does not end up heating your house.

As for the dryer, does anyone know the energy efficiency of the new LG
Tromm condensing dryers? They circulate the moist air from the drum
through a "mist" of cool water, and pump the condensate down the
drain, thus requiring no air exhaust. Eliminating the heat loss from
pumping air outdoors and drawing in cold air has to be a huge net
gain. Not having to continually heat that air stream to dryer
temperature has to be another net gain. Recovering the heat of
condensation from the removed water has to be an efficiency gain.

The question I see is how much water is required to make the condenser
"mist", and how do you convert the cost of that water (and its
removal) into an electric equivalent?

Loren

Posted by Trygve Lillefosse on February 14, 2007, 1:50 pm

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On Fri, 02 Feb 2007 19:38:54 -0500, clare at snyder.on.ca wrote:

>wrote:

>>On 2 Feb 2007 12:05:41 -0800, "Sudden Disruption"

>>...

>>>Which brings up one important exception to this "effectiveness" rule -

>>>the clothes dryer. It blows it's heat outside and also brings in cold

>>>air - you lose. It's a good reason to get a clothes line. Or use the

>>>dryer sparingly.

>>Add the clothes washer and the dishwasher. EnergyStar attempts to

>>include the energy used to heat the water they consume, much of which

>>goes down the drain and does not end up heating your house.

>>As for the dryer, does anyone know the energy efficiency of the new LG

>>Tromm condensing dryers? They circulate the moist air from the drum

>>through a "mist" of cool water, and pump the condensate down the

>>drain, thus requiring no air exhaust. Eliminating the heat loss from

>>pumping air outdoors and drawing in cold air has to be a huge net

>>gain. Not having to continually heat that air stream to dryer

>>temperature has to be another net gain. Recovering the heat of

>>condensation from the removed water has to be an efficiency gain.

If you have a reversable AC, you are even better of since you will
get more heat than you put in. Unlike panel ovens and lightbulbs.

--
SEE YA !!!
Trygve Lillefosse
AKA - Malawi, The Fisher King

Posted by Jesse Spencer on February 2, 2007, 5:51 pm

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> ZERO!

> If you are not cooling your home, EVERY light bulb and appliance is

> 100% efficient.

If you need HEAT in the home then the savings is ZERO.
Another problem with EE devices is also the base cost.
Those CF bulbs cost at least 3x more than standard and some of that cost
is most likely from the energy required to make them.
Same true of other EE devices to varying degrees.

Posted by Eeyore on February 2, 2007, 6:31 pm

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Jesse Spencer wrote:

> > ZERO!

> >

> > If you are not cooling your home, EVERY light bulb and appliance is

> > 100% efficient.

> If you need HEAT in the home then the savings is ZERO.

Not when another source of heat is a lot cheaper which it certainly is here by a
factor of about 3.

> Another problem with EE devices is also the base cost.

> Those CF bulbs cost at least 3x more than standard and some of that cost

> is most likely from the energy required to make them.

> Same true of other EE devices to varying degrees.

The 6 to 15 incandescent bulbs needed in the lifetime of a single CFL easily
exceed the cost of the CFL these days.

Graham

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