2.16.4 Calculation of ideal energy consumption (theoretical value) and energy consumption (theoretical value)
The ideal energy consumption (theoretical value) is calculated based on the reference values for power saving that are set in the Set Green IT Property dialog box. The energy consumption (theoretical value) is calculated based on the settings on individual computers.
For the operating time of a computer, the values for the sample settings in the Set Green IT Property dialog box are used for both the ideal energy consumption (theoretical value) and energy consumption (theoretical value).
The power consumption per hour is calculated as the total value of the combination of power saving settings shown in the following table.
|
No. |
Status of the monitor |
Status of the computer |
Power consumption per hour (W) |
|---|---|---|---|
|
1 |
Usual operation# (30) |
Usual operation# (39) |
69 |
|
2 |
Turn Off Hard Disks (35) |
65 |
|
|
3 |
System Standby (3) |
33 |
|
|
4 |
System Hibernate (0) |
30 |
|
|
5 |
Turn Off Monitor (0) |
Usual operation (39) |
39 |
|
6 |
Turn Off Hard Disks (35) |
35 |
|
|
7 |
System Standby (3) |
3 |
|
|
8 |
System Hibernate (0) |
0 |
Note: In the above table, the numbers enclosed by parentheses indicate power consumption per hour (unit: W). Note that a computer can only be in one of the above statuses at a time. If multiple patterns of power saving settings are operating at the same time, the power saving settings with lower power consumption is selected.
#: Power saving settings are not operating.
Calculation of ideal energy consumption (theoretical value)
The ideal energy consumption (theoretical value) is the value when the judgment criteria for power saving settings that is set in the Set Green IT Property dialog box is applied to the computers and the computers run as defined in the sample settings.
The following describes how to calculate the ideal energy consumption (theoretical value) with the following conditions:
-
Number of managed computers: 100
-
Reference values for the power saving settings in the Set Green IT Property dialog box (default):
-
Turn Off Monitor (AC): Within 5 minutes
-
Hard Disk Turn Off Time (AC): Within 30 minutes
-
System Standby (AC): Within 1 hour
-
-
Sample settings in the Set Green IT Property dialog box (default):
-
Operating time for a computer (per day): 8 hours
-
Time a computer is not operated: 60 minutes x 1 and 10 minutes x 6
-
The ideal energy consumption (theoretical value) is calculated for the time computers are operated and for the time computers are not operated separately. These calculations are based on the values in the above table.
- Time a computer is operated
-
According to the sample settings, the time a computer is not operated (60 minutes x 1 + 10 minutes x 6) is excluded from the operating time per day (8 hours). In this example, the operating time becomes as follows:
8 hours - 2 hours = 6 hours
When a computer is operated, power saving settings are not operating. So, No.1 in the above table is applied. The calculation formula is as follows:
69 x 6 hours = 414 (Wh)
- Time a computer is not operated
-
There are two types ("60 minutes x 1" and "10 minutes x 6") of energy consumption according to the sample settings.
- Energy consumption for "60 minutes x 1"
-
For Monitor Turn Off Time, 5 minutes is set. So, the status of No.1 in the above table continues for 5 minutes, and then the monitor is turned off. For Hard Disk Turn Off Time, 30 minutes is set. So, the status of No. 5 in the above table continues for 25 minutes, and then the power of the hard disk is turned off. For System Standby, 1 hour is set. So, the remaining 30 minutes will be in the status of No.6 in the above table. Thus, the calculation formula is as follows:
(69 x 5 minutes / 60 minutes) + (39 x 25 minutes / 60 minutes) + (35 x 30minutes / 60 minutes) = 39.5 (Wh)
- Energy consumption for "10 minutes x 6"
-
This type of energy consumption is also calculated in the same way as the above type of energy consumption (60 minutes x 1). The status of No.1 in the above table continues for 5 minutes, and then the status of No.5 in the above table continues for 5 minutes. These status changes repeat 6 times. Thus, the calculation formula is as follows:
{(69 x minutes / 60 minutes) + (39 x 5 minutes / 60 minutes)} x 6 = 54 (Wh)
- Calculation formula for ideal energy consumption (theoretical value)
-
The ideal energy consumption (theoretical value) results from multiplying the total energy consumption for the time a computer is operated and for the time a computer is not operated, by the number of computers. Thus, the calculation formula is as follows:
(414 + 39.5 + 54) x 100 = 50,750 (Wh)
Calculation of energy consumption (theoretical value)
The energy consumption (theoretical value) is the value when computers operate following the power saving settings on individual computers and the sample settings (for computers' usage).
The energy consumption (theoretical value) can be calculated in the same way as the ideal energy consumption (theoretical value). The following shows the number of computers, an example setting, and calculation of energy consumption (theoretical value) for that setting:
-
Number of managed computers: 100
-
Computer settings:
-
Turn Off Monitor (AC): 10 minutes
-
Turn Off Hard Disks (AC): 30 minutes
-
System Standby (AC): 90 minutes
This example assumes that all computers have the same settings.
-
-
Sample settings in the Set Green IT Property dialog box (Example)
-
Operating time for a computer (per day): 8 hours
-
Time a computer is not operated: 60 minutes x 1 and 10 minutes x 6
-
- Calculation formula for energy consumption (theoretical value)
-
Energy consumption per computer (theoretical value): (69 x 6 hours) + (69 x 10 minutes / 60 minutes) + (39 x 20 minutes / 60 minutes) + (35 x 60 minutes / 60 minutes) +{(69 x 10 minutes / 60) x 6} = 542.5 (Wh)
Energy consumption for 100 computers (theoretical value): 542.5 x 100 = 54,250 (Wh)
Thus, energy consumption values for individual computers are calculated based on the settings, and totaled as the energy consumption (theoretical value). Note that the energy consumption (theoretical value) is calculated based on only the computers whose power saving setting information can be acquired.