How much does a dehumidifier cost to run per 24 hours?

Condensation on the inside of windows is caused by the temperature difference between interior and exterior. Reduce that difference by placing 50mm into the window reveal on the outside of the house does the job.It doesn't work if you put the polystyrene on the inside. And fire or smoke risk anyway.
Easily made (£20 for 4 windows) and handled.
Proof of the pudding is in this house. NO CONDENSATION on the inside of the windows with exterior shutters and condensation otherwise.
And further proof is my bills..a saving of £60 a year.

Ken68 wrote: »

Condensation on the inside of windows is caused by the temperature difference between interior and exterior.

Not quite. Warmer air can, but doesn't necessarily, carry more moisture than cold air. It's when that air with higher moisture content meets a colder surface, any higher mositure content condenses out.

If the interior window surface is the same temperature as the interior air, then condensation will not form on the windows ... but the warmer heavier water laden air still exists inside the property so water will condense if it hits a cooler surface, e.g. an exterior wall, perhaps behind a wardrobe etc.

The solution to a condensation problem is to remove the increased moisture content of the air inside the property, either by ventilation, the use of a dehumidifier or best of all, don't allow the air to become so water laden in the first instance.

Ken68 wrote: »

Condensation on the inside of windows is caused by the temperature difference between interior and exterior. Reduce that difference by placing 50mm into the window reveal on the outside of the house does the job.It doesn't work if you put the polystyrene on the inside. And fire or smoke risk anyway.
Easily made (£20 for 4 windows) and handled.
Proof of the pudding is in this house. NO CONDENSATION on the inside of the windows with exterior shutters and condensation otherwise.
And further proof is my bills..a saving of £60 a year.

Ken,
We are at cross-purposes.

It is not in dispute that you can prevent condensation forming on the windows. - as said above, a heated rear widow on a car does that as well. However condensation on a window is just a symptom that demonstrates there is humidity.

The purpose of a dehumidifier is to remove the high humidity(dampness) that is in the house. That dampness is in the fabric of the house and furniture etc.

Preventing condensation forming on a window does nothing to remove that dampness.

In fact high humidity is a bigger problem abroad in hot humid climates where no condensation ever forms on the inside of widows and it is necessary to take measures to reduce humidity.

With respect you have no 'proof' that you have saved £60 by putting anything on your windows. Double glazing, triple glazing or even bricking up the window might save a small amount of heat loss. However it will have done nothing to have solved the problem of a damp house.

You have to remove that moisture/dampness, or take measures to prevent the dampness.

DocBrown wrote: »

I think you have to multiply the rating of the device in watts by number of hours used to get KW/h figure i.e 220 watts X 24 hours = 5,280 watts. Divide by 1000 to get Kilowatt/hour figure = 5.28 which is in Units. Multiply units by your electric kWh price - say 11 pence. Total 5.28 X 11 = 58pence per 24 hours or £211.70 per year.
Hope this helps. I've just carried out a rough energy audit on my house and we're using between 6 to 8 units per day.

That would of course only apply if a device did not have a thermostat(or in this case a humidistat).

However with the vast majority of appliances they only run for a period of time and then switch off when the desired temperature/humidity is reached.

This is why the Owl type monitor is quite useless at calculating the cost of running the vast majority of appliances.

For instance your Fridge/Freezer might also have a 220W compressor but typical running costs might be £30-£40 instead of £211.70.