Soldato
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Have a read through the entries headed Entropy and Enthalpy in wikipedia.
Where does used electricity go ?
- Thread starter timciren
- Start date
Along with the normal heat/light/kinetic transfers you also get things such as earth leakage and neutral back feeds depending on the type of load.. eg. Inductive.
On a side note you try and get an Earth leakage figure from a pc manufacturer.
On a side note you try and get an Earth leakage figure from a pc manufacturer.
You can boil water in a kettle and pour the boiling water into a radiator so it is possible, just not very practical and electrical heating costs more than gas heating.
So,
If we treat a well insulated house as a closed system
if we only had electric heating
if the heating is thermostatically controlled,
90% + of the elctricity powering a PC will go to warming a room and 99% +of the energy used boiling a full kettle for a single cp of tea will also heat the house.
Lets assume drinking a cup of hot tea and weeing it down the toilet doesnt count for much heat loss.
If we treat a well insulated house as a closed system
if we only had electric heating
if the heating is thermostatically controlled,
90% + of the elctricity powering a PC will go to warming a room and 99% +of the energy used boiling a full kettle for a single cp of tea will also heat the house.
Lets assume drinking a cup of hot tea and weeing it down the toilet doesnt count for much heat loss.
True, but then you're just using the radiator for its intended purpose anyway; to heat the room. A kettle isn't going to do that on its own.
Soldato
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And even under 100% load a 500watt PSU won't always use 500 watts either if I remember right
Correct, it will use around 550W or more depending on how efficient it is
Actually I think Dutch Guy is right the radiator just speeds up the heat dissipation, it isnt magic, the 3000W kettle will heat it as much as a 300W heater on for 10 times as long
Incorrect.
You look at the input power drawn by a PSU and take that as 100% heat rejection. The PSU powers all of the components so they can't gain their power from thin air, just from the PSU.
Also remember that a PSU isn't 100% efficient and has losses of it's own.
In one room I was calculating heat rejection and found out from a colleagues report done previously on the old PSUs that they were less that 20% efficient. Good old school heaters that also power equipment
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Deleted member 651465
Deleted member 651465
It's like GSCE physics all over again, in here.
"Watt is the measurement of power?"
"???"
"Listen closely... WATT.. is the measurement of power?"
"Ahhh sir, you sneaky *******"
"
"
"Watt is the measurement of power?"
"???"
"Listen closely... WATT.. is the measurement of power?"
"Ahhh sir, you sneaky *******"
"
"
Of course a kettle is going to do that! In each case, it isn't the radiator or the kettle which is providing the energy to heat the room, it is the hot water. You need neither a radiator or a kettle, just the hot water on it's own will heat the room as it cools, but a radiator or kettle stops the water from soaking into your carpet and making it wet whilst it heats your room...
As for the steam, when you boil water, a small percentage of the energy is used to increase the temperature from 20C to 100C, then a high percentage of the energy is used to convert the 100C water to 100C steam - that is technically what boiling is. As the 100C steam condenses to 100C water, the energy released by that process heats the room. As the 100C water cools to 20C, it transfers its heat energy to the room.
The major difference between an electric heater and a kettle is that one of them doesn't go bang if you fill it with water while it's switched on
Soldato
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- Manchester.
It's a heater basically. 99% will go into heat. the other 1% will be light from the monitor or LEDs or sound.
How much of that then stays in the case and how efficiently it heats the air in the room is another story.
Leave it on for free heating.
How much of that then stays in the case and how efficiently it heats the air in the room is another story.
Leave it on for free heating.
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It's like GSCE physics all over again, in here.
"Watt is the measurement of power?"
"???"
"Listen closely... WATT.. is the measurement of power?"
"Ahhh sir, you sneaky *******"
"
Cor you did GCSEs and your old enough to build your own house !!!
House thread is great BTW
Cant believe you found time to take all those pix, excellent planning skills
They would belt kids for calling teachers ******** back in the day
Soldato
- Joined
- 4 Jan 2004
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- ¯\_(ツ)_/¯
Blimey, 20% is pretty poor, having to use 1kw of power in order to generate only 200W, it's quite nice now many relatively affordable SMPS' now achieve 80% or even 90% efficiency without too much trouble.Incorrect.
You look at the input power drawn by a PSU and take that as 100% heat rejection. The PSU powers all of the components so they can't gain their power from thin air, just from the PSU.
Also remember that a PSU isn't 100% efficient and has losses of it's own.
In one room I was calculating heat rejection and found out from a colleagues report done previously on the old PSUs that they were less that 20% efficient. Good old school heaters that also power equipment
Caporegime
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- Leafy Cheshire
It's like GSCE physics all over again, in here.
"Watt is the measurement of power?"
"???"
"Listen closely... WATT.. is the measurement of power?"
"Ahhh sir, you sneaky *******"
"
This, what do they teach people in schools ourdays?