energy

[bentaxle]

BT Yahoo browser
How to cut your energy bill ,ensure your microwave is completely switched off simply powering the clock can use more energy than heating the food ,surely not

[wildwood]

I agree, that is complete rubbish.

[Hawkwalk]

quite possible. Microwaves do not use much energy and are not used for that long and that often. Some appliances use up to 25% of their energy on standby, I doubt a microwave is that high but considering the clock will be on for 24hrs a day then it soon adds up.

[MatydaLover]

It certainly sounds nonsense. Without knowing the power ratings of the devices we can still make a reasonable comparison.

My alarm clock battery lasts a year - the battery is 3V with say a capacity of 1000mAH. That means it uses about 3kWH (3 units) per year.

A microwave rated at 800W used for 10 minutes will use about 0.14kWH. That's about 52kWH per year - 17 times as much.

I'd guess that the microwave clock is more efficient, so it's likely to use much less than 3 units per year. Given the clarity of one's power bill, I don't know how much a unit costs these days! Still, there's a clock on the microwave, the cooker, the boiler controller, the VCR, the strereo ...

[MatydaLover]

... and I've just realised that the alarm clock uses 3WH not 3kWH. A mere factor of a thousand times less. If the microwave clock is similar, then you can forget its consumption.

[eltelioni]

It is not as daft as it sounds.
The power transformer in the microwave is designed for powering the microwave. When it is only powering the clock it is probably very inefficient.
Suppose the microwave is used for 10 minutes per day at 700 Watts. That's equivalent to 5 Watts continuous.
The clock could easily be using 5 Watts or more.
Does anyone have any real data?

[jake-the-peg]

Ye it will depend on the model.

Some older electronics use very inefficient standby modes.

It's not that the clock per se is using the energy it's the power supply sitting in standby.

You see this a lot in TVs there's a huge variation in the amount of power being used in standby mode but more modern devices can be only a watt or less

[eltelioni]

A quick survey suggests anything between 1W & 10W for microwave standby power.
This article suggests it is typically 6W: http://mail.mtprog.com/CD_Layout/Day_2_22.06.0 6/1400-1545/ID23_Ueno_final.pdf

[heathfield]

Interesting... so I checked my old Sharp 1000W microwave oven using a plug-in power meter. After 6 hours on standby the meter reads 0.01 kW (the minimum reading available on the meter). Cooking on full power, it uses1.23kW.

[jake-the-peg]

Right so If Heathfields microwave is one that uses 10 watts over the day (can't be sure because of the limits on his meter) it will use 0.24 KWhr

Which is the equivilent of 11 minutes a day cooking on full power

[heathfield]

Err-um, Jake, the reading of 0.01kW was over a 6 hour period, as stated. Thus the 24 hour useage for the clock alone is 0.04 kWh. At the 10.49p per kWh charged by my electricity supplier, this costs me 0.42p per day, or �1.53 a year. Yep, keeping the microwave switched off would be quite a saving. I could afford an extra half pint of lager once a year! LOL

[sandmaster]

Why is it that the British, when they get some extra cash in their pockets, want to binge drink?