Analyze power draw and requirements for multiple devices and UPS sizing. Part of the DevTools Surf developer suite. Browse more tools in the Developer Utilities collection.
Use Cases
Calculate total rack power draw to ensure circuit capacity before adding new hardware.
Size a UPS for a home lab with multiple servers, switches, and storage.
Estimate monthly electricity cost for a server room based on device wattage and runtime.
Identify high-draw devices that are candidates for replacement with more efficient alternatives.
Tips
Add a 20–25% headroom buffer to your total wattage when sizing a UPS — sustained load above 80% capacity shortens UPS battery life.
Include idle wattage for always-on devices like network switches and NAS units, not just peak wattage from servers.
Convert watts to kilowatt-hours (kWh) to calculate monthly electricity cost: (watts × hours/day × 30) / 1000.
Fun Facts
Data centers consumed approximately 200–250 TWh of electricity globally in 2022, representing about 1% of global electricity demand, according to the IEA.
A standard 1U server draws 200–400W at peak load; a GPU-equipped AI training server can draw 3,000–10,000W — roughly equivalent to 10–50 household desktop PCs.
Power Usage Effectiveness (PUE) was introduced by The Green Grid in 2007 as the standard metric for data center energy efficiency; world-class facilities achieve PUE below 1.1.
FAQ
What's the difference between TDP and actual power draw?
TDP (Thermal Design Power) is the maximum heat the cooling system must dissipate — it approximates peak power draw but CPUs typically run at 60–80% of TDP under normal server loads.
How do I calculate UPS runtime?
Runtime (hours) = (battery capacity in Wh) / load in watts. Most UPS manufacturers publish runtime curves in their datasheets for common load percentages.
