What does it cost to run a server at home?

Less than you'd think.

The box's processor has a 15 W base power. Running all year, that's about 131 kWh, or about $25 at the U.S. average residential rate. Actual draw at light load is usually lower.

Compare that with renting a cloud server with the same 16 GB of memory: about $146 a month on average, before storage and bandwidth.

And a single small server at home needs no cooling plant. If your home runs on solar or a renewable plan, your websites do too.