Efficiency vs Efficacy?!?!! A clarification
The machine is tested both for energy use and washing ability that is, indeed, efficacy.
If the machine scored "G" in the standard test I can't see why it wouldn't be possible!
It did an inferior job with much more energy than a "traditional" front loader.
On this website I learned for the first time that people overseas soak and use additives all the time in their top loaders. I never did that, just dump clothes and detergent and I'm done. The stains are shifted without pretreating.
Now, mind that the eurolabel test is very tough so "normal" stains will be removed easily by any machine but the test patterns of dirt and their composition is way harder to defeat than normal dirt that one can have in their wash.
It must be noted that according to our consumer association 70% of the washloads done could be washed with no detergent and visually get no difference in cleanliness. You will only have the "clean" odour factor and bacterial ablation.
Another clarification about self heating and not self heating machine: as it was pointed out by Haxisfan, you won't save a single cent as the water, unless you have a solar collector, must be heated anyways! And if you want a double fill machine, front loaders have that too, our beloved Candy makes them, beloved Miele too and so does Indesit and Electrolux!
Now let's make a couple of calculations! (With the average Italian utility costs)
The Maytag, for a hot wash, would cost:
- 0,168 cubic metres of water x 1,50€ per cubic metre = 0,25 €
of them roughly 1/3 must be heated (wash + 2 rinses)
- 56 litres x 45°C (delta T from 15°C) x 4,186 kJ/L/°C = 10,549 MJ
1 kWh is 3,6 MJ, at 0,23 €/kWh, the cost is
- 10,549 / 3,6 * 0,23 €/kWh = 0,67 €
let's add the pure electrical consumption of the machine
- 0,63 kWh * 0,23 €/kWh = 0,15 €
Dryer costs (assuming electric, full stated load, vented dryer, energy class "C")
Now you should note that the energy class is defined with a load with a residual moisture of 60% typical of a 1000 rpm machine.
We assume the figures to be 10% higher (like a 800 rpm machine) even if the spinning speed is only 650, but since the drum is bigger, the machine extracts like a 800 rpm one with a smaller drum (see the same "D" class for spinning typical of those machines)
Figures are:
- 0,67 kWh/kg * 8 kg = 5,36 kWh
let's add a 10% more because of the slow spin speed
- 5,36 + 10% = 5,90 kW/h
at the usual 0,23 €/kWh
- 5,90 * .23 = 1,36 €
So using those machines, with electricity only, one would spend 2,43€ excluding detergent.
Getting an equivalent sized front loader would cost
energy (including self heating of water to 60°C)
- 1,36 kWh * 0,23 €/kWh = 0,31 €
water used
- 0,060 cubic metres * 1,50 €/cubic metre = 0,09 €
Drying it in the very same dryer as above but spun at 1400 rpm (44% of residual moisture vs circa 70%)
let's consider 10% less in energy use
- 8 kg * 0,67 kWh/kg -10% = 4,82 kWh
at the usual 0,23 €/kWh it is
- 4,82 * 0,23 = 1,11 €
That all sums up to 1,51 € to have your wash done (excluding detergent)
The difference is almost 1€ per wash! And let's not forget that both water and electricity are tiered so using more of either drives the price up!
At 70 washes per year at 60° it is some 65 euros in difference!
I know that it is a wimpy amount compared to food! But you should consider that you're not wasting as many resources to accomplish the same thing.
