Your math is wrong. If the Celeron runs 65W at idle then it is consuming at minimum 1.56kWh a day, at a price of €0.20 per kWh you're looking at a minimum operating cost of €113.88 a year.
You didn't factor in that days have 24 hours, not one hour.
Sorry you have to hear it this way, but a butt towel requiring a wash in detergent and even more water than you just flushed is less eco-friendly than two squares of toilet paper.
Since Twitter is now private, we'll never know the real numbers, but the paper value of the Twitter brand itself being cast aside is a huge non-monetary loss.
Google is not a search engine. It's an advertising service. Their whole business model revolves around a critical mass of eyeballs, which flock to free services. This will never happen for the average user.
Imagine being this petty.