How to calculate the energy consumption?

[Perene]

Guys, I have this computer:

* PSU: Seasonic 520W

* Core i7 4770
* MB Gigabyte H97M-D3H
* Video card: R7 265
* 8 GB RAM (Corsair Vengeance 1600 MHz)
* HD Samsung SATA 750 GB
* HD WD Blue 1 TB
* SSD Samsung EVO 840 120 GB
* CPU Cooler: Hyper 212X

*********** * LG W2452V - LCD **********

I used a calculator and got a result of 300W. I needed to know the exact value (in watts) to discover the kilowatt-hours (kWh) in a month.

This is that well-known calculator:
http://www.extreme.outervision.com/psucalculatorlite.jsp

Apparently this computer wastes 216 kWh in a month. That is because it is running 24/7. My last energy bill showed an usage of 560 kWh.

This is what I find odd - the computer is what is wasting more energy! For example, the monitor has 80W. 80 X 18h/day is equivalent to 5 times less what this PC is consuming. The kWh is worth 50 cents with taxes.

One more thing: most of the time the PC is not running a game or rendering a video. Instead, it's using the browser and uploading files. Soon I'll reduce the use dramatically.

Is everything I said... correct?

Should I assume at least 300W to calculate things?

 

[fralexandr]

at idle your computer is likely using significantly less than 100W

http://www.p3international.com/products/p4455.html
there are various devices that can measure power usage over time at an outlet. Many hardware stores sell them.

 

[Insert_Nickname]

Apparently this computer wastes 216 kWh in a month. That is because it is running 24/7. My last energy bill showed an usage of 560 kWh.

Is that bill for a quarter, monthly or...? Is it your total energy bill? Because if you want to save power, you should check your appliances before your computer. That'd be your fridge, freezer etc.

I doubt if that PC uses much more then 0.05KWh idle. Load is properly around 0.2KWh. This translates to 1.2KWh daily at idle. Times 365 is 438KWh yearly assuming idle. So 560KWh yearly doesn't seem unreasonable.

at idle your computer is likely using significantly less than 100W

http://www.p3international.com/products/p4455.html
there are various devices that can measure power usage over time at an outlet. Many hardware stores sell them.

I'd start there. Hard numbers makes for easier math...

 

[mikeymikec]

Easier (and probably more accurate) method of measuring - get a watt meter. The watt meter I have will tell me its current usage in Watts, its current usage in KWh, and the (I think) the total usage of the device during the entire time the watt meter has been receiving mains power for. Then you pick a typical computer usage day and see what the result is.

 

[Perene]

Is that bill for a quarter, monthly or...? Is it your total energy bill? Because if you want to save power, you should check your appliances before your computer. That'd be your fridge, freezer etc.

216 kWh in a month. Even if this computer wastes 100W instead of 300W (peak) it will waste something equivalent to a new refrigerator, used 24/7 (72 kWh).

My last bill showed 560 kWh wasted in a single month.

What do you think about those figures?

P.S. This computer is never in idle. It's either uploading files to a server, rendering a video or being used in other way. When not being used at all I turn it off.

 

[Insert_Nickname]

My last bill showed 560 kWh wasted in a single month.

What do you think about those figures?

I think you're confusing a few things. To use 560KWh a month would require something like a LGA-2011-3 + quad SLI Titan rig running full throttle 24/7/30. That's a lot of power we're talking about here.

Depending on how many people are in your household, 3000 to 4000KWh yearly is considered normal. At least were I live (Denmark). That's for two adults and two children.

 

[Perene]

I think you're confusing a few things. To use 560KWh a month would require something like a LGA-2011-3 + quad SLI Titan rig running full throttle 24/7/30. That's a lot of power we're talking about here.

Depending on how many people are in your household, 3000 to 4000KWh yearly is considered normal. At least were I live (Denmark). That's for two adults and two children.

560 kWh = everything that was consumed here. The computer included in that number. And in the last 30 days.

What I was thinking is that even if that computer, running 24/7, was wasting 100W, it would be equivalent to what a fridge consumes running 24/7 also in 30 days. Which is 72 kWh.

560 kWh includes TVs, 2 fridges, 5 lamps, etc.

Is that clear now?

In my original calculations I considered 300W for the computer. That is equivalent to 216 kWh in a single month if running 24/7.

 

[Insert_Nickname]

560 kWh = everything that was consumed here. The computer included in that number. And in the last 30 days.

What I was thinking is that even if that computer, running 24/7, was wasting 100W, it would be equivalent to what a fridge consumes running 24/7 also in 30 days. Which is 72 kWh.

560 kWh includes TVs, 2 fridges, 5 lamps, etc.

Is that clear now?

Yup. It wasn't immediately clear if those 560KWh were total for a month or just for the PC alone.

Compared to what I use (~135KWh/month summer, ~185KWh winter) its still a bit on the high side. You may still want to check if you've got any energy guzzlers somewhere. Especially older freezers can use a lot (5-10KWh daily). Replace any incandescent light-bulbs with LEDs, and you'd properly save more then by focusing on your PC...

A KWh meter is an extremely effective way of tracking down what exactly is using power.

In my original calculations I considered 300W for the computer. That is equivalent to 216 kWh in a single month if running 24/7.

As I posted, I severely doubt if your system even breaks 50W idle. That's were the 0.05KWh came from (36KWh/month). But you'd have to use a KWh meter to be sure of course.

Also, if the system isn't doing anything at idle, you can use hibernation. That way, you'll only use standby power (sub 1W) and there are no drawbacks to it.

 

[mfenn]

Easier (and probably more accurate) method of measuring - get a watt meter. The watt meter I have will tell me its current usage in Watts, its current usage in KWh, and the (I think) the total usage of the device during the entire time the watt meter has been receiving mains power for. Then you pick a typical computer usage day and see what the result is.

Agree. The best way to figure out the usage is to measure it. Most home power meters have both instantaneous power (W) and energy usage (kWh) measurement features.

 

[piasabird]

What kind of USB devices do you use? Is there a wireless keyboard? Make sure both the monitor and the computer are going to sleep when not in use.

Here is another question. Have you tested your router energy usage? Maybe other people are using the router when you are not.

I really need to get a kilowatt meter to see how much my TV and computer are using as a point of reference. I have my computer on for a lot of hours along with my 40" HDTV. There has got to be some device you can plug into the wall that computes energy use over time like a green energy power usage monitor system.

I think houses could be designed to store energy and then use battery power during peak usage time could save a home owner a lot of money.

 

[JackMDS]

100W x 24 x30 = 72,000 Wh aka 72KWh

Agree. The best way to figure out the usage is to measure it. Most home power meters have both instantaneous power (W) and energy usage (kWh) measurement features.

Double Agree, and to do so all you need is this - http://www.newegg.com/Product/Produc...9SIA24G0P60122

 

[greenhawk]

if you must have a exact number, you need a power meter to run the computer through.

as the the computer, it depends a lot on what you are doing. Just uploading files will not let a computer get into a true "idle" state as the HDD has to be working at least, which keeps other parts awake. Power usage also depends if you are overclocking or have disabled any of the inbuilt power saving features as well.

As to calling the computer "idle" when it is encoding video, then that is wrong. When encoding video a computer is using a lot of power (CPU at full speed). The only time the computer might use more is when gaming (adding GPU to the power consumption list).

Without a power meter, the only option to work out power load is to watch your power meter (both over time, and if yours has a moving wheel, how many rotations it does per minute). Doing this when the only thing that changes is your computer being on gives an idea of what the computer is using, but the process is made harder with fridges (they turn on and off as needed) and if there are other people in the house when you are doing the tests.

Generally, the largest electricity user is heating, either electric heating or for heating water.

Appliances can use a lot of power as well over time, but they are generally only on for short periods of times (ie: cooking).

TVs can use a lot of power when on as they generally only have two modes of operation, on or off. A old TV, or worse, a plasma TV can use enough power to make a PC look like nothing.

 

[piasabird]

I noticed a big reduction in energy costs when I went from an electric dryer to gas.

Things that use lots of power:
Refrigerator
freezer
Heating
Cooling
water heater
electric stove
Portable electric Heater 1500+ watts Maybe use an infra red heater or ceramic heating element.
Electric blanket/pad.

A monitor tends to use more power than a computer. To save money don't use a giant monitor. A computer without a video card only sips power at a low rate. Of course, if you want to play video games you need the video card which will use up to 3 times the power. If you want to play, you have to pay.

Other problems in the summer mostly are that some appliances make a lot of heat inside the house than you have to run the air conditioner to cool them off.

 

[piasabird]

I noticed you have 2 hard drives of 1 gb or less. Maybe invest in a larger hard drive of say 2 TB or maybe you need 2 for some reason.