Savings ReportA spanish City Council with 3000 computers where

they were previously used in a controlled way

Workings

• The software measures the PC energy state and the user activity each second.

• After a certain amount of inactivity time, the PCs are put in low power state

On

StandBy

Off

Active

Inactive

Math

• The power used in each state is inserted in the software, and the program does the calculus aggregating data.

90W

5W

1W∑ Tiempo

Data capture

• A database stores historic data and allows us to make comparisons

• Analysis tools allow us to do a tight project tracking during the lifetime of it (in real time)

This date started

the policies

The effect is noticed by the

appearance of stand-by

states (yellow bars)

Comparative criteria• Both periods: without holidays or

reduced working hours.

• 1) Initial period:

• without applied policies

• 2) Final period

• with applied policies

• with the platform stabilized

Compared periods

• Data from 'Period 1' were captured from 06/09/2010 to 6/22/2010. On average, 1.845 PCs were connected daily.

• Data from 'Period 2' were captured from 09/01/2010 to 09/14/2010. On average, 1.789 PCs were connected daily

Results

• 53,9 kWh saved per PC and year

Graphic comparative

Objectives met :-)

• The savings were anticipated on July 13 by using simulations

• Formula required by the customer: (projected savings - real savings) / projected savings)* 100 < 20% of deviation.

• Results: (54,5 - 53,9) / 54,5)*100 = 1,1 %

Recommendations

• Do not take this information to the letter. The software estimates are conservative: when used data from the PC without considering the load of CPU, peripherals, disk, etc, the usual consumption power is much greater than estimated and therefore the savings are higher.

• As the result depends on the use of people and their behavior (not a laboratory testing out of reality), and no one works the same from day to day or week to week, it is impossible to consider the conditions between 2 periods as 100% equivalent . To accomplish this we should clone two people´s behaviors, or put two subjects in a laboratory (one with software and one without it) and force them to use the PC in EXACTLY the same way.

• Wait a few months and see the electricity bill. The result will be visible where most noticeable (comparison from year to year).