What This Calculator Does
The Server Power Consumption Cost Calculator estimates how much it costs in electricity to keep one or more servers running continuously. Servers typically operate 24 hours a day, every day, so even a modest difference in power draw or electricity price can add up to significant annual expense. This tool converts a server's wattage into a monthly and yearly dollar figure so you can budget, compare hardware, or build a business case for more efficient equipment.
How to Use It
Enter the server's average power draw in watts (check the PSU rating or, better, a measured value), your electricity price in dollars per kilowatt-hour (kWh), and the number of identical servers you want to model. The calculator assumes round-the-clock operation and a 30-day month, and also shows daily cost, annual cost over 365 days, and the energy used in kWh.
The Formula Explained
Power in watts is divided by 1000 to get kilowatts. Multiplying by 24 gives daily kilowatt-hours, and multiplying by 30 gives monthly energy. Finally, multiplying by the price per kWh produces the monthly cost: $$\text{Monthly Cost} = \frac{\text{Watts}}{1000} \times 24 \times 30 \times \text{Price per kWh}$$ The total scales linearly with the number of servers.
Worked Example
Suppose a server draws 500 W and electricity costs $0.15/kWh. Daily energy = \(500/1000 \times 24 = 12\) kWh, costing \(12 \times \$0.15 = \$1.80\) per day. Over 30 days that is $54.00 per month, and over 365 days about $657 per year — per server.
FAQ
Does this include cooling costs? No. Data center cooling can add 30–100% on top of the IT load (this is the PUE factor); this calculator only covers the server's direct draw.
Should I use nameplate or measured wattage? Measured (actual) wattage is far more accurate. PSU nameplate ratings are maximum capacity, not typical consumption.
Why 30 days but 365 for the year? The monthly figure uses a standard 30-day month for simplicity, while the yearly figure uses a full 365-day year for accuracy.
