Datacenter: Electricity

Even the most advanced and powerful network without power is merely a stack of metal scrap. No matter how sophisticated your setup is, you could be missing out if it doesn’t get and use power efficiently. Here are some basic terms to learn about the power of the data center.

AC and DC Power

When it comes to powering your data center, you have two options—AC or DC power. AC (alternating current) is what you think of when you plug in a device, appliance, or tool (120 or 240 volts). AC changes direction multiple times per minute to optimize performance. DC (direct current), based on batteries, flows in one direction, making it more efficient. Most colocation data centers rely on AC, but many companies now integrate DC or a mix to improve efficiency and minimize downtime.

Power Usage Effectiveness (PUE)

PUE is a metric reflecting the ratio of total power entering a data center versus the power consumed by IT equipment. It indicates efficiency: lower ratios mean more energy goes to the IT equipment rather than supporting infrastructure. Determine PUE by dividing total facility energy by IT equipment energy. Aim for a PUE as close as possible to 1. Ideal target values are 1.5 or lower for existing centers and 1.4 or lower for new facilities. A PUE of 2.0 or higher indicates inefficiencies that increase costs.

Data Center Efficiency Metrics

• Amperes (amps): The actual moving electricity running through wires to servers and devices.
• Volts: The “push” that drives electricity from the source to devices. Typical outlets provide 110–220 volts, depending on location.
• Watts: The actual power consumed by devices. Complex operations, multi-tasking, or specialized hardware like GPUs increase wattage.

Power at the Core of Information

All electricity needs to be distributed efficiently. Key requirements include:

• Servers: Devices doing the work, storing data, and supporting operations.
• Cooling: Servers generate heat; power equipment is needed to prevent damage and extend lifespan.
• Inverters: Store and supply power during AC disturbances to prevent downtime.
• Support: On-site staff require power for workstations, cameras, HVAC, and security systems.
• Security: Alarms and physical security measures require energy to protect the data center.

Understanding Power Use Effectiveness (PUE)

PUE helps you track how energy is consumed in the data center. A high PUE indicates inefficiency with excessive non-IT energy use; a low PUE indicates optimal operation. Calculate PUE as total facility energy divided by IT equipment energy. Lower ratios reflect more efficient power usage for IT tasks rather than supporting infrastructure.

Target PUE values:

• Existing data centers: ≤1.5
• New data centers: ≤1.4
• PUE ≥2.0: review for inefficiencies and potential cost savings