I have run a home server for the last four years. It handles Plex media streaming, file backups, a home automation controller, and a few Docker containers for various services. For most of that time, it ran Windows 11 Pro because that was what I was comfortable with.

Last month, I moved it to Ubuntu Server. The performance difference was marginal, but the power consumption difference shocked me. My server went from idling at 65 watts to 28 watts. Over a year, that adds up to significant savings.

Why Windows Uses More Power Idle

The core issue is that Windows keeps background services running even when the system is not doing anything useful. The indexing service, telemetry, Defender real-time scanning, Windows Update checks, and a dozen other processes keep the CPU awake and prevent it from entering deeper sleep states.

Linux, especially a server-oriented installation without a desktop environment, has none of that overhead. My Ubuntu Server installation boots to a terminal with nothing running except the services I explicitly enabled. The CPU spends most of its time in idle states that Windows could not reach on the same hardware.

The Hardware

My server hardware did not change. It is an older Intel NUC with an i5-8259U, 16GB RAM, and a 512GB NVMe SSD with two external USB drives for storage. The only change was the operating system.

Measuring the Difference

I used a watt meter plugged between the server and the wall outlet. Before the switch, I measured 65W at idle with Windows 11 after boot, 78W under light load with Plex streaming, and 92W with file transfers and multiple Docker containers running.

After switching to Ubuntu Server, I measured 28W at idle, 42W under light load, and 58W with the same workload. The Windows system was using roughly twice the power for the same tasks.

The Calculation

At 65W versus 28W idle, the difference is 37W. If the server runs 24 hours a day, that is 0.888 kWh per day. At the average Indian electricity rate of roughly Rs 7 per kWh, that works out to Rs 6.2 per day or about Rs 2,260 per year. For a machine that is always on, the savings are real.

If your server runs under load more often, the gap narrows but still favors Linux. Under heavy load, the difference was 92W versus 58W, a 34W gap.

What I Lost by Switching

There were trade-offs. Windows made it easy to connect to the server through Remote Desktop with a full GUI. On Linux, I manage everything through SSH and the command line. That requires more familiarity with terminal commands.

I also had to figure out replacements for a few Windows-specific tools. Plex runs natively on Linux, but I had to set up permissions for the media drives. Home Assistant replaced my previous home automation setup. Docker works identically on both platforms, so my containers transferred without issues.

Printer sharing was more complicated. On Windows, network printer sharing was click-and-configure. On Linux, I had to set up CUPS and configure Samba for Windows clients on the network.

What I Gained

Beyond the power savings, the Linux server is more stable. My Windows server needed a reboot every few weeks for updates. My Linux server has been running for 48 days without a restart as of this writing.

Security is simpler. Fewer running services means fewer attack surfaces. No antivirus consuming CPU cycles. No remote exploits targeting Windows services that I do not need anyway.

Maintenance is lighter. Updates on Ubuntu take seconds and do not require reboots unless the kernel is updated. When a reboot is needed, I choose the timing.

Who Should Make the Switch

If you already comfortable with the Linux command line, the switch is a no-brainer. The power savings alone justify the effort, and the stability improvement is a bonus.

If you rely on a GUI to manage your server, you can install a lightweight desktop environment like Xfce on Ubuntu Server. It will still use less power than Windows because the background services overhead is lower. If you need Active Directory integration or run Windows-specific server applications, you may be better off sticking with Windows.

Bottom Line

Switching my home server from Windows to Linux cut my power consumption by more than half. The annual savings are modest for a single machine, but the stability and control improvements are significant. If you run a server 24/7 and are comfortable with the command line, Linux is the more efficient choice.