I'm sorry, but I must suggest that the whole idea of electricity consumption has become a little lost in translation here. To speak of refrigeration appliances for one moment first of all, these have long been a silent drain of electricity, but in recent years manufacturers have been forced to make strides in cutting running costs, mainly by redesigning the appliances so that they have much more insulation.
Frost Free freezers once used to guzzle electricity and when energy rating labels were first used, it was quite shocking to see how much power a frost-free appliance would use in comparison to a standard model. I do not have the technical knowledge as to how all this has been refined, but take a look at the ratings for any new frost-free appliance and you will see that energy consumption is at an all time low.
As for heated appliances, I feel to compare a heated appliance to something like a vacuum cleaner is to compare apples with oranges. As we established earlier on, a vacuum cleaner motor can be designed to work more efficiently and at a lower wattages, to produce the same suction as a poor quality high-wattage lampshade. The fact is that for what ever the reason, manufacturers have chose to take the path which they have done. The comparison I make is only the same as me owning a table lamp with a white shade and 40w bulb, against my neighbour next-door owning the exact same lamp but with a dark brown shade and having to use a 60w bulb in an attempt to create the same amount of usable light. I use this example as it is exactly what has happened in our respective homes.
However this is in respect of appliances where they are run consistently and the time take to complete the task -be it vacuuming a carpet or using the lamp to read a book- is entirely at the discretion of the user. A hob, a kettle, a tumble-dryer (at least a sensor model) all require a certain temperature to be achieved and the faster this happens, the more energy is saved overall. I cannot stress the use of the word 'overall' enough, because it is not sufficient to say kettle A runs as 2000 watts, whilst kettle B is 3000 watts, therefore kettle B uses more electricity, because overall (that is to say over periods of time) kettle B runs for a lesser amount of time than the lower wattage alternative. The same applies to a hob; the higher the watts, the quicker it will come up to temperature and thus shut-off until such time that the thermostat cuts back in.
Another example where a watt-for-watt comparison means very little (and this I use now as I know it is a very real source of confusion for a good deal of consumers) is in the way that one could not compare a 2000 watt fan-heater to a 2000 watt oil radiator, as the fan heater will always consume more electricity due to the design of it, that is to say there is nothing inside it to retain heat to continue warming a room, unlike an oil radiator which will retain heat and continue to heat a room even when the heater is off.
