ok will agree to disagree look at my edited text about pay see what you think
There's no need to agree to disagree - you just need to learn the difference between power and energy and then we'll be in agreement.
Washing machine energy usage.
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There's no need to agree to disagree - you just need to learn the difference between power and energy and then we'll be in agreement.
the equation as far as i see it the values are time related as in H [hours] so cannot be a total without including the value +times =
if its a total then you can divide it as its not a variable that is dependant on time as in i have £5 lets share it rather than i earn £5 an hour lets share it
if its a total then you can divide it as its not a variable that is dependant on time as in i have £5 lets share it rather than i earn £5 an hour lets share it
If a pay analogy helps, then consider the following:
I want you to fix my boiler and you and two other engineers have quoted me £60 to do so.
You might take it easy and do it in 3 hours, in which case you have earnt the equivalant of £20/hr.
Someone else might take 2 hours, in which case they have earnt the equivalent of £30/hr (but worked harder in each hour)
Someone else still might really go for it and only take 1 hour, in which case they have earnt the equivalent of £60/hr.
In all three cases the total amount payable remains at £60, the overall energy consumed remains the same, all that has differed is the amount of instantaneous effort ('power') and the duration ('time') that that power has been applied. Cost = effort x time. Energy = power x time.
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ok lets think off another example a 18v 5ah battery in an hour will be 18x60x5=5400kw total capacity so perhaps the issue is they are working out the energy used as a 1 hour time frame then transferring it to a another value as in now a total divided actual time
so infarct 2 equations as in average over 1 hour to give a value off perhaps 500 total then another equation to divide the use over another time span off perhaps 2hr 45 so very sloppy and confusing as much much easier to to say total energy used in this cycle and length off cycle so cost per hour pointless as the total is the value off the action [the wash ]
so infarct 2 equations as in average over 1 hour to give a value off perhaps 500 total then another equation to divide the use over another time span off perhaps 2hr 45 so very sloppy and confusing as much much easier to to say total energy used in this cycle and length off cycle so cost per hour pointless as the total is the value off the action [the wash ]
ok a very interesting thread
i am very open to learning perhaps the choice off "h" doesnt help
In all fairness, the kWh unit is somewhat unusual in that we are more used to dealing with reciprocol units i.e. something per something such as miles per hour, but kWh is a multiplicative unit i.e. it is something multiplied by something. Specifically it is power multiplied by time, and is particularly useful when you are more interested in the overall combined total (energy consumed, in this case) than the individual component parts, particularly when those individual components will vary during the process being measured e.g. with a washing machine cycle there'll be a period of heating water, several periods of spinning at different speeds, a period or two of pumping etc all of which draw different amounts of power for different lengths of time. It is the total energy consumed that is usually of interest, although secondary to that might be the length of time taken (e.g. dishwasher 'Eco' programmes that might consume relatively little energy compared to other programmes but can take 4+ hours to complete which might not be acceptable and lead to a preference to get things done quicker even if it means paying more due to the additional energy required to do so).
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Crude, and potentially false, analogies rarely serve the purpose of helping explain a subject. You're better off sticking to the subject itself.
If you must though, the unit of capacity for a battery is amp-hour (or watt-hour if you factor in voltage too thus indicating total energy capacity). Thus, your battery with a capacity of 5Ah (or 18x5=90Wh to put it in units of energy) could, leaving aside real world nuances, supply 5A for 1 hour, or 2.5A for 2 hours, 1A for 5 hours etc before depleting. Different amounts of power for different amounts of time, but the same overall energy provided.
Again though, stick with getting your head around energy consumption of washing machine programmes otherwise you risk confusing things more than they already are!
The unit of kWh is not a 'per hour' measurement (that would be kW/h). kWh represents the total energy consumed (and therefore total cost payable).
it is in the equation because Energy = Power x Time. Note again though that it is a numerator i.e. it sits above the line, it is not a denominator sitting below the line of a fraction. There is no per in it like there is in mph (i.e. where speed = distance / time).
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If my explanations aren't helping (entirely likely; there's a big difference between being able to understand a subject and teach it) if you Google energy power difference have a read of a few different takes on the subject which whilst all amounting to the same conclusion will use different ways to explain it and one of them - or a combination - might help the penny to drop and everything fall into place.
(I'd love to see @Mr Chibs' face when he wakes up to see this and discovers we spent the whole night talking about his little question!
)
(I'd love to see @Mr Chibs' face when he wakes up to see this and discovers we spent the whole night talking about his little question!
)
Despite all of the explanations, you are still failing to understand. It is the total cost of the wash, just as £45 would be the total cost of the job you mention above.
If the 0.26Kwh mentioned is multiplied by the cost of one unit, that will be the cost of the entire wash.
Kwh can be compared to the amount fuel in the tank of your car. If you have 10 gallons in the tank, you can maybe do 200 miles with it. You can do the 200 today, tomorrow, or next week, but it will still cost you the 10 gallons irrespective of when you do the 200 miles.
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(I'd love to see @Mr Chibs' face when he wakes up to see this and discovers we spent the whole night talking about his little question!
I needed a couple of hours to go through that lot... I haven’t even set today’s question.
I Need to do a load of washing This morning, so which is the most economical programme again?
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If you had smart meter and turn everything off in house and run washing machine it will tell you the cost won't it. See this in customers houses as the cost jumps when I'm about. Ha. I see them looking the tight fisted bunch. I seem to be able to use £1 of electricity easy enough in winter with heaters, fans and tools
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Watt = Joule per second, so a kWh since there 3600 seconds in an hour = 3600 kJ there is no time. Seems daft to have hour in the name when nothing to do with time.
I tried to measure out of interest what power items use, these
have been around for some time, and I was a one time trying to save power used, however although one could see with a kettle the power used to boil, the washing machine was virtually impossible.
It weighs the load and adjusts the cycle to suit load, so every wash had a different result, even using same program. Also if any item needs washing again as not clean, then need to adjust results, but unless there is a mark to show not clean, then to know not clean as there is still bacteria or even soap on the cloths is again impossible.
I remember in Algeria having a problem with rash likely caused by cloths not being rinsed fully, it turned out the people in charge of doing the washing were putting soap power in the section for conditioner, we filled the section in the draw with filler so could not be used, cured the rash, however there was nothing one could see on the cloths to show they we contaminated with soap, they looked clean.
I now use something like this
so I can see when my battery has completed its charge, but the so called smart meter is useless to measure what a single item uses as very rare everything turned off. Still not worked out how when Freddy Boswell claps his hands on the advert the lights go on/off? I don't want a smart meter, we clap our hands to stop cat doing things, don't want lights turning off/on
I tried to measure out of interest what power items use, these
It weighs the load and adjusts the cycle to suit load, so every wash had a different result, even using same program. Also if any item needs washing again as not clean, then need to adjust results, but unless there is a mark to show not clean, then to know not clean as there is still bacteria or even soap on the cloths is again impossible.
I remember in Algeria having a problem with rash likely caused by cloths not being rinsed fully, it turned out the people in charge of doing the washing were putting soap power in the section for conditioner, we filled the section in the draw with filler so could not be used, cured the rash, however there was nothing one could see on the cloths to show they we contaminated with soap, they looked clean.
I now use something like this
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