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Showing posts from March, 2006

PC Electricity Consumption

With electricity quickly approaching $2 per watt per year, leaving a computer powered is a very expensive proposition. I found that I could power down my PC and save over $100 per year.

Here's how to accurately estimate how much your computers cost to operate.

Calculating Costs

In order to calculate the cost, I first calculated my total cost per watt per year. With my recent electric bill in hand, I used the following formula:

$ per Watt-Year = (bill's $amount) ÷ (bill's KWH) × 8.766

Given the following calculation, my electricity rate is a staggering $1.51 per watt-year:

$30.29 ÷ 176 KWh × 8.766 = $1.51

With this watt-year value, it's easy to accurately estimate how much your computer (or clock radio or refrigerator) costs per year.

Computer Cost per Year of Operation

Mac MiniPowerBookiMac G4iMac G5eMac 700WinPCOn19 [$25]
14 [$18]
38 [$50]
58 [$76]
91 [$120]
108 [$142]
Sleep mode
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Impact on Air Condi…