Wednesday, September 10, 2008

Surveyor PC Power Management 9 - Tracking Savings

Issue:
After doing the configuration you want to see some results.

Quick:
Use the Verdiem reporting tool, Track your daily power usage from bills.

Visual/Learning:
Verdiem comes with a nice reporting tool and has a number of reports that can be run. The report that I am using here is the Baseline Energy Comparison. Since we kept our workstation on 24x7 My baseline is easy to figure so we did not run Serveyor in baseline mode to gather data.



I am asking the reporting tool here to generate a report based my 60 computers that I have currently installed with the Verdiem Surveyor client. The server database knows when computers were on and off. I am asking Surveyor to look at the data between July 1 and Aug 21 and compare that data with my Pre-Surveyor power usage.

My measured power usage for a workstation was 140Watts or .14Kilowatts x 24 hours a day x 365 days = 1226 Kwh per year per computer. I plug that number in to the report tool. Our power rate seems to vary by season between 12 and 16 cents per KWh. Right now I am using 13 cents but that may be lower then our average rate. We discovered that our workstations use about 7 watts whether they are in standby mode or turned off, this is just want the power supply draws when it is plugged in. The report tool has a place to enter those numbers as well.
Now the report tool generates several charts. The one below shows that we are saving 62.5 %. Over one year that adds up to about $100 per computer or about $6000 for all 60 computers. Image what the dollar and energy savings might be for a large company year after year.


Now the reporting tool is great but I want to see the results on the actual electric bill. I went to finance and got our bill for the company site where I have deployed the software. Form the bills I learned our cost, days billed, and total bill fluctuates a fair amount, but our daily average power usage is pretty flat. I believe that daily average may be a good indicator of our savings.


My prediction is that the daily average will drop but by how much. If I take the yearly power savings from the report for all 60 machines, 45,992 KWh and divide that by the days in a year (365) I get 126 KWh. I expect that by saving 62% on our workstations, our average daily usage on our bill will drop by 120 KWhs which is 15% of the 800 KWhs that we currently use.

The next bill should come in a few weeks and I will post the results when they do.


---September 16th update ---
We got the bill and it is hard to see what we are saving because our daily usage is not as flat as I first suspected. Looking at last years average usage, the bill normally goes up in the Summer. But here is how the average is tracking compared to last years average. The dark blue line is this year. Our average usage is down considerably from last year. I also checked the average temperatures for each month this year and last year and they are about the same according to records at http://www.westerndisastercenter.org. So this drop has nothing to do with a cooler Summer. We have also been replacing our old monitors with flat screens and I suspect that has added a bit to the power savings as well. Here you can see the difference is about 200KWh per day in September.

5 comments:

Damjan said...

Hello Jimmy, I have another question.

Are there any other type of reports - per group or workstation consumption?

And another - can you specify different kWh costs as here where I live we have two price ranges: 6am to 10pm for 0.11€/kWh and 10pm to 6am for 0.9€

I think that the reporting tool could offer few more options, but maybe on the other hand - the main thing is that PCs shut down - not how flashy and customizable reports are. Right?

Jimmy said...

There are a dozen or so different reports. I have not looked at them in detail because our situation was pretty simple. After a quick look, I did not see a place to specify two different price ranges. I believe the hand held power meter that I was using does have a way to specify different amounts for different times. You could perhaps get an average from that device to use in your reports.

Damjan said...

Thank you

Damjan said...
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Damjan said...
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