In addition to not enough information-
there are problems in using 240V 50Hz equipment at 120V 60Hz. If one wants
to use European appliances, then many are available for 60Hz, 120 or 240V
operation. If it is properly designed for the voltage and frequency that it
is used at- then efficiency differences are minor or negligable.
It is also now sometimes difficult to determine just where a given appliance
is designed or made as manufacturers are international. In some cases a
"European" brand is made in the US while "American" brands are made in
Europe and some damn good appliances are designed and made in New Zealand.
Europeans had to face high energy (and water) costs long before North
America so efficiency at a higher capital cost was worth while. Now North
America is waking up to the same problem.
you mean appliances like refrigerators, washing machines, hot water heaters,
i think you should consider carefully some of the many pitfalls in your
proposed course of action:
cost of importing appliances and parts.
cost of resizing/replacing all circuit breakers and rewiring as needed. cost
of replacing outlets.
astronomical repair costs and unbelievably long repair times.
nil resale value of non-standard power plant and appliances. low resale
value of the property in the event you decide to sell and move.
non-ability to reconnect to grid in the event of generator failure or lack
of whatever fuel or power source you go with.
possible fire hazard if someone unwittingly plugs in the wrong thing.
possible electric code infraction depending on state/local.
a major PITA having to remember to check EVERY electrical device that comes
into your house for compatibility.
i'd recommend you have a little talk with a local electrician and an
appliance store. next fire up the little calculator program on the computer
and see what your "savings" of the next 5 years might be.
Regarding "more"efficient 240 V. appliances...
While in Europe, I observed that something as simple as a small
incandescent light bulb operating on 240 volts was not so efficient.
In fact, just to touch it was to feel that it was as hot as hell. I
don't remember what the wattage was, but it gave about the equivalent
amount of light as a 40 watt bulb in the US.
Edison knew what he was doing when he designed his system. He came up
with voltages of 100, 110 (and later 120) volts as the optimum for
carbon filament incandescent lighting.
I think the Euro definition of "more efficient" means smaller, cheaper
conductors, longer runs for appliance circuits and possibly less
voltage drop, etc.
Many Euro hot water heaters are point-of-use. There is something of a
myth that these are more "efficient" than the American practice of
having large tanks of heated water in their basements and garages on
"standby". Factoring the increased capital cost and more complex
maintenance for these "point-of-use" systems tends to show that, in
many cases, the actual cost is higher.
Well, it would still help if you said what appliances you
are thinking of.
US-style fridge/freezers have become popular in UK at least
in last few years, and some US manufacturers have started
making them to EU efficiency standards. You could try
asking a US manufacturer for one. Note that their identical
US models are still completely off the bottom of the EU
energy efficiency scale (as people who try buying in the US
and importing to the EU rapidly discover), so you would have
to specifically ask for one to EU energy efficiency standards.
If more people did this, they might make them available in
the US too.
For washing machines, which is another item where energy
efficiency very is widely different between US and EU, the
problem you are going to find is obtaining the European
advanced cloths washing detergents which EU machines use.
They just don't exist in the US, as they won't work in US
So as I said, some idea of what appliances you are thinking
of would be useful.
Actually European washing machines do exist in North America. Some are
bloody expensive. As for the detergents- they are now readily available. A
few years ago, what you say would be quite true and many washers are still
the top load agitator units which are initially cheaper. However, as
happened in the 1950's with circuit breakers , European designs are taking
over more and more of the market- some are made in Europe and others are
made in the US or Canada. Europeans have long been more concerned with
energy and water savings than North Americans.
Most "appliances" (e.g.: dishwashers, uWave, washing maches) which now run
on 120 would likely be "better" were they to be operated on 240.
Personally, I think anything that draws more than10 amps at 120 should be
re-designed to operate on 240.
Amen. BUT in US and europe, most "utility" (as compared to "effect")
lighting is flourescent. To a good approximation, efficienty doesn't
change with supply voltage. With the US system, 240 volt stuff would
usually require two pole switches and two pole breakers. These might
offset the savings in copper ahd I^2*R losses.
"Decorative" lights are moving toward low voltage systems with built in
transformers. Again, the supply voltage isn't much of a factor.
But incadescent lighting may soon be considered obsolete.
Maybe so; maybe no. In an "all electric" home, it may start to make sense
to replace the hot water tank with a 5 kW heater with, say, 12kW demand
based systems. It also may make sense to move the heaters closer to the
point of use.
In the case of a dishwasher, a case can be made to plumb the machine with
COLD water and let it heat the water with a 240 volt heater. It would have
the further advantage of starting each cycle with COLD water. This will
permit some washing before the food is "baked" on. Ditto for a clothes
washer: it might make sense for a 240 volt powered appliance to just take in
COLD water and heat it locally to whatever temperature suits the
Oil is becoming relatively "cheap" again but everytime oil peaks the nuke
power plants start looking more acceptable.
I have seen the demand type electric water heaters on display. At present
they are very expensive. Since there is so little to them, I see no
reason why the can't eventually be sold for something on the order of $50
for a 10KW demand heater. At that price, any failure would result in a
replacement of the entire unit rather than sending out someone to figure out
the controls and safety interlocks.
Cheap demand heaters would be placed near the point of use. A bathroom
might have separate heaters for the sink and bath. It might even have a
"tempering" heater for the water to the toilet tank. A truly integrated
system would just adjust the water heater set point rather than "mix"
separate hot and cold supplies. There would be some interesting safety
problems as a person in a tub would be "adjusting" a 10kW electrical
I actually had a chance to try out this experiment. At the time my
wife ordered a new dishwasher with the internal heater element. The
cycle timer would not advance until the operating temperature was
reached. We tried it with the exclusively cold water (actually turned
the water heater off and let it cool down for a few hours). The
result was that it took something like 1 1/2 to 2 hours to do a load
It takes a long time to heat water exclusively with this element to
near boiling, which is what the dishwasher requires. The cycle timer
would not advance until the operating temperature was reached. Don't
forget there are something like 5 - 6 fills cycles and each requires
heating a few gallons to near the boiling point.
The conclusion was that pre-heating the hot water was a good thing and
there was no reason to change from current practice. If you are in a
typical household that uses hot water for bathing, clothes washing,
general kitchen use and dishwashing, it is more efficient to heat up
the hot water in bulk and have a means of efficient, insulated
storage. For a large heater in a multi-family dwelling unit, such as
an apartment building, the advantages are even greater.
Yes, in my house almost all the lighting is fluorescent, and the
filament lighting is 12V.
In UK, for a few years now, new builds and remodels have to
include lighting at 40 lumens/Watt (IIRC) or higher in proportion
of the heavily used areas of the house, and the lampholders
must be of a type which will not take filament lamps (which
don't reach anywhere near 40 lumens/Watt efficiency).
You think wrong then.
Euro designs and customs vary widely from one country to another.
The appliance regulations are all common though.
In UK, most heating and hot water is done by natural gas, although
there is some oil and a little electric. Gas appliances used for
heating now have to be >90% efficient (which means condensing
operation). Instant on-demand gas water heaters are typically around
30kW and are now very popular. Electricity derived from fossel
fuels is all under 50% efficient before it even leaves the
power staion. Hence we avoid electric heating whereever possible.
That's how ours work. They don't normally have a hot fill. There
are two reasons: hot water onto protein based food cooks it onto
the plates and makes it harder to get off. It comes off easily
when the water is cold. Secondly, the small amount of water used
in an EU dishwater makes non-viable to hot fill, as you will likely
not get much if any hot water run to the end of the pipe before
it's finished filling, and then you just waste that energy as
the water in the feed pipework goes cold.
EU washing detergents would be largely destroyed by hot fill.
EU washing machines do a profiled temperature wash -- a period
of washing at different temperatures which match the optimum for
the various different constituents of the low temperature washing
detergents. This means they have to cold fill (or temperature
controlled mixed fill at around 30C/86F), and work their way up
to 40C or 45C/113F slowly which is the highest needed by the
detergent. Again, it's questionable if it's worth connecting up
the hot inlet -- many people don't bother as the volume of hot
water used by an EU washing machine is tiny, and it certainly
isn't worth it unless the pipe run is short.
These exist in the UK, exactly as you describe. However, the
poor efficiency of electricity generation means they aren't
a sensible choice. Also, 10.5kW (highest commonly used instant
electric heater in UK) doesn't generate a very good shower -- you
get a much better and more efficient shower from a condensing
gas heater. Even an old obsolete non-condensing gas heater is
still twice as efficient as fossel fuel electricity generation.
Instant electric water heaters have historically been more common
in Germany, where you can find them rated up to 25kW, but domestic
3-phase electricity supply is more common there than in the UK.
That's about what I would expect. The heater only runs on the 120 and,
likely, doesn't draw more than 700 watts if that.
The "new order" of appliances would run on 240. The heater likely would be
2 kW. It would still take some extra time, however.
A marginally sized heater in this application would waste energy because
during the temperature ramp up, only a portion of the energy would be
increasing water termperature. The other portion would just be countering
the heat loss.
The US is quite the "consumer driven" place.
What that means in practice is the we just don't care one way on the other
about "thermodynamic" efficiency. Modern life DEMANDS that a house have
good electrical service and the distribution costs of electricity are mostly
covered by the rate base.
Thus, it might may "themal sense" to burn natural gas in a 90% furnace
rather than use it in a 50% power plant but to the customer who wants a warm
bathroom, it makes more sense to used electric from the 50% power plant.
Well, when we "run out" of hot water I have found that in summer we can bare
stand using the "hot" water that's just run through the water heater and
picks up the heat from the 4 kW element. I would "guess" that a point of
use 12kW shower heater might give acceptable service with a flow restriction
on the water supply. But from what you say, I suppose something like 16 kW
would be needed.
Checking my UK one... It takes 4-5 pints of water for the main wash
cycle. The only other fill which gets heated is the last rinse,
which is really just used to heat the dishes prior to the drying,
and only uses about half the water of the main wash. So that's
less than a gallon of water which is heated.
Well, you were hampered by the combination of an inefficient machine,
compounded by it being designed to run off the limited power available
from a US socket outlet -- a double wammy. Neither of these problems
are an issue anywhere in EU.
Also, you need to test the cleaning effectiveness with a variety
of foodtypes. Some types of protein (egg, porrage, etc) are more
difficult to clean in a hot fill system, as the heat cooks the
protein into longer chains, making it impossible to break down,
so the cleaning of them depends mainly on mechanical agitation.
Conversely, they clean easily in cold water.
Why do you want to store it? That can only add losses,
and the possibility that the store runs out.
You actually completely failed to address the efficiency issue
at all, even though you seem to have reached a conclusion.
While the cold water may be better for getting the chunks of food off and
not baking onto the dishes, and hence the dishes look clean, but they will
not be sanitary. Detergents safe enough to use in the home will not kill
the bacteria left on the dishes. Only heat will suffice to kill the little
buggers. The typical commercial dish washer rinses the dishes then goes to
town with the soap and hot water. And that hot water, at least in the US
has to be up around 180 deg F otherwise the local health department starts
getting upset with the restaurant owner.