Calculating power consumption
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Ravi Bhavnani wrote:
Power = Volts x Amps (132W)
That would be for DC. For AC you have to integrate the absolute value of the voltage times the current over a full sinusoidal cycle. If I remember right, that gives you a factor of 0.707 of the DC value.
The evolution of the human genome is too important to be left to chance.
These are RMS figures so it's still P=V*I.
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Ravi Bhavnani wrote:
Power = Volts x Amps (132W)
That would be for DC. For AC you have to integrate the absolute value of the voltage times the current over a full sinusoidal cycle. If I remember right, that gives you a factor of 0.707 of the DC value.
The evolution of the human genome is too important to be left to chance.
As Elaine says, the quoted AC line voltage is the RMS value. UK 240Vrms AC peaks at nearly 340V.
Stability. What an interesting concept. -- Chris Maunder
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Use the range hood. And open a window. Or just open a window. Or just cook things that smell nice...
Shog9 wrote:
Use the range hood. And open a window. Or just open a window.
The kitchen doesn't have a window - the nearest window is the one in the living room - which we keep open. But it still takes a while for the odors to vanish.
Shog9 wrote:
Or just cook things that smell nice...
We are Indian, remember? :-)
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
They cycle the air through a small filter which makes them ok for dust. But stuff that smells can get stuck to the walls via humidity so its not going to be filtered at all.
Todd Smith
Todd Smith wrote:
They cycle the air through a small filter which makes them ok for dust. But stuff that smells can get stuck to the walls via humidity so its not going to be filtered at all.
Yeah, these things seem to be meant for visible dust particles and not for odor.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
We bought an Air Purifier (Holmes) yesterday, and its manual says it can be left on permanently. But I am a little concerned about its power consumption - I mean if it's 400W or something I don't want to leave it on 24 hours a day. Unfortunately it doesn't mention power consumption anywhere on it :-( I checked the manual, the specifications, searched their website, searched the body of the equipment etc. I did find the following info : 120 V, 60 Hz, 1.1 Amps AC only Now using those bits of data, is there some formula to calculate the power consumption? Or is that indeterminate? Thanks in advance.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)Something else to keep in mind is that stated power consumption is not always equal to actual power consumption. Many products will list power consumption at full load, which is almost never reached. I'm not an expert on air purifiers, but I would expect your actual power consumption to be less than listed. Also, some devices cycle themselves through states where they may be fully on for a while, then in idle state for a while. I guess what this really boils down to is this: you have an air purifier, you obviously thought it was important enough to pay to purchase it, now you need to pay to use it. Either you want it, or you don't. Is that harsh? I don't mean for it to be. Rick.
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132 Watts * 24 Hours = 3.17 KWh. If you pay $0.10 per KWh, then your device costs you about $0.32 per day which is a bit less than $10 per month.
danmorin wrote:
132 Watts * 24 Hours = 3.17 KWh. If you pay $0.10 per KWh, then your device costs you about $0.32 per day which is a bit less than $10 per month.
Thanks - that's lower than I had imagined then. Though I don't know my rate - it's in therms (whatever that means).
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
danmorin wrote:
132 Watts * 24 Hours = 3.17 KWh. If you pay $0.10 per KWh, then your device costs you about $0.32 per day which is a bit less than $10 per month.
Thanks - that's lower than I had imagined then. Though I don't know my rate - it's in therms (whatever that means).
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
Nishant Sivakumar wrote:
Though I don't know my rate
The cost per KWh is written on your utility bill. On my last bill, I has to pay $0.0522 per KWh, which would cost about $5 per month for operating your device.
danmorin wrote:
The cost per KWh is written on your utility bill. On my last bill, I has to pay $0.0522 per KWh, which would cost about $5 per month for operating your device.
Okay I checked now and found that I had to pay $ 0.122 per KWh (I wonder why my rate is twice yours). But yeah - about $10 then.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
Nishant Sivakumar wrote:
Though I don't know my rate
The cost per KWh is written on your utility bill. On my last bill, I has to pay $0.0522 per KWh, which would cost about $5 per month for operating your device.
Plus, your device wont be drawing 1.1 amps continuously.
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danmorin wrote:
The cost per KWh is written on your utility bill. On my last bill, I has to pay $0.0522 per KWh, which would cost about $5 per month for operating your device.
Okay I checked now and found that I had to pay $ 0.122 per KWh (I wonder why my rate is twice yours). But yeah - about $10 then.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)Nishant Sivakumar wrote:
I wonder why my rate is twice yours
The answer is Government Regulation, the same as telecoms used to be regulated. The government passes a law preventing competition of production and/or distribution of electricity, thus granting the power utility a monopoly over a geographical area. The corporation can charge almost as much as they want - there is no price cap. This is analogous to telecom regulations. In the 80's we used to pay long distances $0.35 per minute. Since the telecommunications have been de-regulated, there is more competition which drives prices down. Bell Canada no longer has the monopoly.
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Nishant Sivakumar wrote:
I wonder why my rate is twice yours
The answer is Government Regulation, the same as telecoms used to be regulated. The government passes a law preventing competition of production and/or distribution of electricity, thus granting the power utility a monopoly over a geographical area. The corporation can charge almost as much as they want - there is no price cap. This is analogous to telecom regulations. In the 80's we used to pay long distances $0.35 per minute. Since the telecommunications have been de-regulated, there is more competition which drives prices down. Bell Canada no longer has the monopoly.
danmorin wrote:
The government passes a law preventing competition of production and/or distribution of electricity, thus granting the power utility a monopoly over a geographical area. The corporation can charge almost as much as they want - there is no price cap.
:omg: Why would any government pass such a law?
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
danmorin wrote:
The government passes a law preventing competition of production and/or distribution of electricity, thus granting the power utility a monopoly over a geographical area. The corporation can charge almost as much as they want - there is no price cap.
:omg: Why would any government pass such a law?
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)Nishant Sivakumar wrote:
Why would any government pass such a law?
In return for the monopoly the utilities were required to wire sparely populated rural areas that wouldn't be econoically viable otherwise. In some states the monopolies have been deregulated and forced to compete with varying degrees of success. It's been blamed for the blackouts in california a few years back (dunno if this is an accurate accusation or not). In my state of pennsylvania we haven't had any problems. PEople in cheap power areas saw little change, people in expensive areas generally saw prices drop, as power from the expensive nuke plants ended up being sold only to other utilities to cover production gaps when they shut facilities down for maintaince instead of directly to consumers. People who want to pay extra for the privilage of green (wind) power also are allowed to do so. :)
-- Rules of thumb should not be taken for the whole hand.
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Shog9 wrote:
Use the range hood. And open a window. Or just open a window.
The kitchen doesn't have a window - the nearest window is the one in the living room - which we keep open. But it still takes a while for the odors to vanish.
Shog9 wrote:
Or just cook things that smell nice...
We are Indian, remember? :-)
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)Nishant Sivakumar wrote:
We are Indian, remember? :)
"Blast!" ;) When next i make it out to Atlanta, i'm teaching you two to cook yeast bread. You'll have people making up excuses just to hang out in your kitchen...
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Nishant Sivakumar wrote:
Why would any government pass such a law?
In return for the monopoly the utilities were required to wire sparely populated rural areas that wouldn't be econoically viable otherwise. In some states the monopolies have been deregulated and forced to compete with varying degrees of success. It's been blamed for the blackouts in california a few years back (dunno if this is an accurate accusation or not). In my state of pennsylvania we haven't had any problems. PEople in cheap power areas saw little change, people in expensive areas generally saw prices drop, as power from the expensive nuke plants ended up being sold only to other utilities to cover production gaps when they shut facilities down for maintaince instead of directly to consumers. People who want to pay extra for the privilage of green (wind) power also are allowed to do so. :)
-- Rules of thumb should not be taken for the whole hand.
Ok - thanks. That makes sense.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
danmorin wrote:
The government passes a law preventing competition of production and/or distribution of electricity, thus granting the power utility a monopoly over a geographical area. The corporation can charge almost as much as they want - there is no price cap.
:omg: Why would any government pass such a law?
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)Nishant Sivakumar wrote:
Why would any government pass such a law?
There is a win-win situation of having a regulation. First, the corporation does not have to worry about competition, thus boosting its profits by charging a much higher fee and reducing its costs by lowering the quality of its products & services. On the other hand the politicians receive more money from "owning" a percentage of the corporation. Politicians also claim they have control over that industry, which is good to gather votes from economic-ignorant voters (the majority of the population knows nothing about economics, and it is not in a government-funded school that you learn sound economic theories). As in politics, there is always a looser. This time, the looser is the resident which has to foot the bill with the extra costs. Why would any corporation want to be regulated, if there is no benefit? If you have a great idea, such as producing electricity or offering long distance calls, why involve politicians and have the state/government own a percentage of your enterprise? Would you prefer to keep all the profits for yourself, instead of "sharing" profits with politicians after paying all the applicable taxes. There is no benefit of having politicians and bureaucrats in your business, unless you can receive privileges from the government, such as a competition-free environment and special loans and subsidies from the government. Then, it makes sense to have a state-owned enterprise where you keep the profits when things go right, and the government pays if there are deficits. Of course, the "government" is funded by taxpayers, so when the government pays something to a corporation, it is our money given to the corporation. Big corporations need regulation so suppress small companies (competition). Large corporations are inefficient and the only way to keep their large market share is to prevent small companies to enter their market. This is a long debate, but to get started you are welcome to take a look at the article "Why is Medical Care so Expensive?" (http://www.mises.org/story/2285[^]).
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Nishant Sivakumar wrote:
We are Indian, remember? :)
"Blast!" ;) When next i make it out to Atlanta, i'm teaching you two to cook yeast bread. You'll have people making up excuses just to hang out in your kitchen...
Shog9 wrote:
When next i make it out to Atlanta, i'm teaching you two to cook yeast bread. You'll have people making up excuses just to hang out in your kitchen...
:laugh:
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
Nishant Sivakumar wrote:
Why would any government pass such a law?
There is a win-win situation of having a regulation. First, the corporation does not have to worry about competition, thus boosting its profits by charging a much higher fee and reducing its costs by lowering the quality of its products & services. On the other hand the politicians receive more money from "owning" a percentage of the corporation. Politicians also claim they have control over that industry, which is good to gather votes from economic-ignorant voters (the majority of the population knows nothing about economics, and it is not in a government-funded school that you learn sound economic theories). As in politics, there is always a looser. This time, the looser is the resident which has to foot the bill with the extra costs. Why would any corporation want to be regulated, if there is no benefit? If you have a great idea, such as producing electricity or offering long distance calls, why involve politicians and have the state/government own a percentage of your enterprise? Would you prefer to keep all the profits for yourself, instead of "sharing" profits with politicians after paying all the applicable taxes. There is no benefit of having politicians and bureaucrats in your business, unless you can receive privileges from the government, such as a competition-free environment and special loans and subsidies from the government. Then, it makes sense to have a state-owned enterprise where you keep the profits when things go right, and the government pays if there are deficits. Of course, the "government" is funded by taxpayers, so when the government pays something to a corporation, it is our money given to the corporation. Big corporations need regulation so suppress small companies (competition). Large corporations are inefficient and the only way to keep their large market share is to prevent small companies to enter their market. This is a long debate, but to get started you are welcome to take a look at the article "Why is Medical Care so Expensive?" (http://www.mises.org/story/2285[^]).
Ok - that was what I had initially thought it would be - that politicians get a cut. But Dan Neely's post gives another view - that it helps bring power to low-populated areas too (that's what the companies have to do in return for the monopoly benefits).
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
Ok - that was what I had initially thought it would be - that politicians get a cut. But Dan Neely's post gives another view - that it helps bring power to low-populated areas too (that's what the companies have to do in return for the monopoly benefits).
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)It is true the corporations are required to bring power to low-populated areas, however this is to make politicians look good. The myth is that without the politicians, there would be no power in low-populated areas and/or the prices would be very high. Think about it, why would a corporation want the government to force selling power to a low-populated area and lose money? Corporations want to make more money. If a law makes them lose money, they would not sponsor it and never beg (lobby) politicians to pass such law. In the case of power regulation, the law gives the power utility a monopoly over a geographical area. A good reading is "The Law" by Frederic Bastiat written in 1849. You can also find this masterpiece in MP3 format.
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It is true the corporations are required to bring power to low-populated areas, however this is to make politicians look good. The myth is that without the politicians, there would be no power in low-populated areas and/or the prices would be very high. Think about it, why would a corporation want the government to force selling power to a low-populated area and lose money? Corporations want to make more money. If a law makes them lose money, they would not sponsor it and never beg (lobby) politicians to pass such law. In the case of power regulation, the law gives the power utility a monopoly over a geographical area. A good reading is "The Law" by Frederic Bastiat written in 1849. You can also find this masterpiece in MP3 format.
Thanks for the info Dan - I fully agree with you. Whatever be the cost of service differences between Canada and Georgia, it can't be high enough for me to have a rate that's more than double yours. Obviously someone's making good money on this :-)
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*) -
We bought an Air Purifier (Holmes) yesterday, and its manual says it can be left on permanently. But I am a little concerned about its power consumption - I mean if it's 400W or something I don't want to leave it on 24 hours a day. Unfortunately it doesn't mention power consumption anywhere on it :-( I checked the manual, the specifications, searched their website, searched the body of the equipment etc. I did find the following info : 120 V, 60 Hz, 1.1 Amps AC only Now using those bits of data, is there some formula to calculate the power consumption? Or is that indeterminate? Thanks in advance.
Regards, Nish
Nish’s thoughts on MFC, C++/CLI and .NET (my blog)
Currently working on C++/CLI in Action for Manning Publications. (*Sample chapter available online*)I haven't bothered to read past the first few postings. Anyway, here is the answer: Power consumed = Voltage * Current * power factor. Power factor equals 1 (the maximum it can be) for a purely resistive load. However, a motor which has windings would definitely have inductive load as well and that would reduce the power factor. Capacitances also reduce the power factor. The reason inductances and capacitances reduce power factor is because in an inductive circuit, current lags behind voltage and so I = V/R (where I denotes the current, V denotes the Voltage and R the resistance) would not stritly hold. The sinusoidal waveforms of voltage and current would show that the waveform for current is behind the waveform for voltage with an inductive load. In a capacitive circuit, current would lead voltage, counter-intuitive though it might seem. Power factor is what is used to compensate for this phenomenon in calculations. For large inductive loads such as motors, it is not uncommon to add a capacitor to the circuit to improve the power factor of the circuit to bring it closer to 1. And yeah, ignore the crap about RMS, the factor of 0.707, etc. They are all valid statements by themselves except that voltage specified is already the RMS (Root Mean Square) voltage. Those of you who don't want to check your EE books (which I bet most of you didn't crack open even during your college days!), here is a wiki reference: http://en.wikipedia.org/wiki/Alternating\_current So, your answer is 120 volts * 1.1 amps * 0.9 = 120 watts. (0.9 is a good approximation for the power factor of most induction motors.) The class meets again at the same time next Tuesday. :-D