electricity usage

[Delboy]

If the shower was run 4 times a day for 15 minutes, you would have almost come to the 8 units per day, which doesn't include heating, cooking or lighting. I know you say 5 minutes for shower per day, but I often say I only had 3 pints when I actually had 5.

You didn't mention hot water either, I presume you have an immersion heater? Put that down for a few units per day. These are generally around the 3kW mark, so can use a unit in 20 minutes.
Leo

No, for sure the shower is run less than 5 minutes a day. The GF is always late in the morning and so has no time to stand in there for ages, except maybe the w/e. I go to the gym and shower there in the morning.
Our hot water comes off of the heating which is GAS. We've never switched the immersion on.

I've convinced the gf to use the old shower, i.e. hose from the mains, for a few weeks to see the effect this has. I already unplug all appliances at night or when not in use so there's nothing on standby. And as I said, all bulbs are the energy savers but even then, we never have lights on when not in the room except for the hall.

It's very hard to get to the meter as it's outside the building, hard to access etc. But I'll try switching off the trip switch and seeing does the meter stop spinning. I'll also get a reading over an average day and w/e.
Will report back.

Thanks for the help

 

[ClubMan]

It's very hard to get to the meter as it's outside the building, hard to access etc.

Really? How does the EBS meter reader access it? If it's a matter of the key needed to open the box then these are readily available and normally provided to householders.

But I'll try switching off the trip switch and seeing does the meter stop spinning. I'll also get a reading over an average day and w/e.
Will report back.

That would be a good idea.

 

[Leo]

Your central heating circulation pump will be using power as well so, check out its rating, probably 200W plus.
Leo

 

[owenm]

Modern PC's are "energy star" compliant whcih means they run at 15 watts or less when on but not in use, this come to €1.51 per month plus usage of 2 hours per day at max €3.36 comes to a grand total of €9.74. You save €3 euros a month by switching it off when not in use.

 

[fandango1]

All this discussion of charges got me thinking at home last night and I started to calculate how much everything costs to run. Hoping someone will be able to tell me if I am working it out properly....e.g.

The sticker on my fridge says that it 160w which is 0.160Kw. Does this mean it uses 0.16 units of electricity per hour? If so, that works out at 2 cent an hour (based on a rate of 12.73 cent an hour) or 48 cent a day.

Is that correct?

 

[fullerand]

The sticker on my fridge says that it 160w which is 0.160Kw. Does this mean it uses 0.16 units of electricity per hour? If so, that works out at 2 cent an hour (based on a rate of 12.73 cent an hour) or 48 cent a day. Is that correct?

As far as I understand it, the power rating of your fridge says that the maximum power it will use is 160W. The amount of power it actually uses while running will depend of various factors such as the internal temperature setting, the temperature of the room it's in, and what food is inside it.

AFAIK the only way to tell for sure how much power an appliance uses over a certain period is to use a power monitor socket like the one I linked to above. I bought one yesterday and have already proven to my girlfriend that my computer isn't costing us millions! Worth the investment just for that

BTW, bear in mind that 12.73 is the cost before VAT - comes to just over 14c with VAT.

 

[ClubMan]

Home kitchen appliances should also state (on the EU mandated energy rating sticker normally found on the casing or inside the appliance cavity) their average daily/yearly (e.g. fridges/freezers) or per cycle (e.g. washing machines and driers) running energy consumption in kWhs which is more relevant than the raw W rating when estimating running costs. See here.

 

[Delboy]

did a reading over 24 hours as was talked about. Used exactly 6 units.
And I recorded what appliances/lights we used over this period, which was:

Lights - various, about 5 hours in total..all energy efficient bulbs.
Cooker - 2 hobs...20 mins in total.
TV - 8 hours...a lot I know, but i was off sick from work and olympic curling is so addictive!!!!
(the video and dvd would be on standby for this length as well).
Computer - 2 hours (comp is brand new).
Heating 4.5 hours (but is GAS), but uses a timer.
Fridge. (no sticker on this giving power...as it's oldish,maybe 5-7 years, and came with the apt.- but it's on the top temp setting inside)
MISC-Kettle boiled about 5 times. 2 radio alarm clocks.

I switched off the power in the apt and checked the meter - it was'nt moving so it's not external hall lights etc thats feeding off the meter.
We did'nt use the electric shower...stuck to the hose which works off the emersion where the water is heated by Gas. And no washing machine was used either.

6 units seems very high, especially when u look at the leaflet the ESB sent out with their last bill.....
They said 1 unit =:
100 watt bulb for 10 hours
or
electric cooker = cooking for 1 person for 1 day
or
TV = 6-9 hours....

it does'nt add up... any thoughts on this

 

[ClubMan]

I you switched off the master switch on your fuse/switch board and you still ostensibly used 6 units in a 24 hour period then it sounds to me like something is up and something/somebody is using your electricity possibly without authorisation. Get the ESB out to check it.

 

[Delboy]

I you switched off the master switch on your fuse/switch board and you still ostensibly used 6 units in a 24 hour period then it sounds to me like something is up and something/somebody is using your electricity possibly without authorisation. Get the ESB out to check it.

no -knocked off the trip switch and checked the meter to make sure it was'nt moving and it was'nt. put the trip back on and then used 6 units in 24 hours which was made up of the appliances etc i noted above...

sorry for the confusion

 

[Zeus]

My understanding is that any equipment using a cable with a transformer will use electricity as long as the cable with transformer is plugged in (with power/socket switch on).

e.g. a(my) laptop or mobile phone. So when the laptop is fully charged (green light), the same amount of electricity will still be used as long as the cable with transformer is plugged in (with power/socktet switch on).

I do not know if the power/wattage of a piece of equipment (e.g a router) refers to the router itself (small) or to the transformer (larger and what you pay for) ?

 

[ClubMan]

no -knocked off the trip switch and checked the meter to make sure it was'nt moving and it was'nt. put the trip back on and then used 6 units in 24 hours which was made up of the appliances etc i noted above...

sorry for the confusion

Oh - that's different so. You must have appliances using the 6 units so. Try switching off and plugging out everything and see what happens. Not sure how practical this is for 24 hours this time of the year.

 

[Leo]

My understanding is that any equipment using a cable with a transformer will use electricity as long as the cable with transformer is plugged in (with power/socket switch on).

e.g. a(my) laptop or mobile phone. So when the laptop is fully charged (green light), the same amount of electricity will still be used as long as the cable with transformer is plugged in (with power/socktet switch on).

Not true.

I do not know if the power/wattage of a piece of equipment (e.g a router) refers to the router itself (small) or to the transformer (larger and what you pay for) ?

Generally applies to the combination.
Leo

 

[Zeus]

Leo, can you expalin why you believe this is not true ?
I would have thought that a transformer using electricity from the socket in one coil would not know whether some equipment is plugged in to pick up the new voltage/current from the other coil (unless newer transformers can do this).

Could a vailid test be to remove the laptop from the transformer cable which is still plugged in. If the transformer will not use electricity, it will not dissapate heat, if it still uses electicity, the transformer will dissapate heat ?

 

[Leo]

Leo, can you expalin why you believe this is not true ?
I would have thought that a transformer using electricity from the socket in one coil would not know whether some equipment is plugged in to pick up the new voltage/current from the other coil (unless newer transformers can do this).

All transformers will have a certain no-load loss, but this is generally negligible and is mainly down to the resistance in the copper used in the windings. This no-load loss will result in a heating of the transformer, as energy can neither be create or destroyed, it must be converted into another energy form.

Ignoring all losses, the current in the primary coil is directly related to the current in the secondary, so zero current in the secondary results in a zero current in the primary.

Could a vailid test be to remove the laptop from the transformer cable which is still plugged in. If the transformer will not use electricity, it will not dissapate heat, if it still uses electicity, the transformer will dissapate heat ?

The only valid test would be to measure the current drawn under full load and no-load conditions.
Leo

 

[Delboy]

Oh - that's different so. You must have appliances using the 6 units so. Try switching off and plugging out everything and see what happens. Not sure how practical this is for 24 hours this time of the year.

everything that used power in the 24 hours i've listed. must be the fridge...thats all i can put it down to....

 

[ClubMan]

6 kWh units per 24 hour period seems high for a fridge. What make/model?

The fridge should have a label on the cabinet or inside the fridge itself detailing its electricity usage in terms of kWh per 24 hours or something similar. My cheap and cheerful (nasty?) Candy half and half is a D (energy efficiency) rated appliance and uses c. 1.56 units (kWhs) per 24 hours. Obviously actual usage depends on environmental conditions, thermostat setting etc. but that's a rough guide. More modern and energy efficient applicances should probably use less but some (e.g. US style big fridge/freezers) could use more. Check your fridge for this label and see what it says. You could always plug it out for an hour or two and see if the meter stops totally. Presumably your fridge is working OK, is adequately ventilated at the back/sides, doesn't have excessive amounts of dust/dirt on the external elements at the rear (these should be hoovered/dusted every few years to ensure maximum efficiency) etc.