Thread by @JohnHyphen

Something mysterious has been happening to some clocks on the European continent. From Portugal to Poland, from Denmark to Turkey, some clocks have been running slow. And it’s all because of a row between Serbia and Kosovo. A thread.

Normal wall clocks and watches keep time with a quartz crystal, cut into the shape of a tiny tuning fork, which vibrates at a constant frequency when electricity passes through it. (it's super cool and you should read about it en.wikipedia.org/wiki/Quartz_cl…)

But clocks which plug into the mains electricity – on ovens, microwaves, central heating, radios, DVD players etc – use the frequency of the electricity grid to keep time. The standard frequency in Europe is 50Hz, 50 oscillations per second.

The electricity grid across much of continental Europe is heavily interconnected, so electricity produced in one place can meet demand elsewhere. All these countries in green are so connected that the grid frequency is synchronised.

To keep frequency stable, production and consumption of electricity has to be balanced. If power consumption is lower than production, the frequency is higher; if consumption is higher than production, the frequency is lower.

If you REALLY want, you can watch the European grid frequency in real time, as it dips below 50Hz and then corrects as supply responds to demand. swissgrid.ch/swissgrid/en/h…

But Serbia and Kosovo, not on the best terms at the best of times, have been having a disagreement about energy supply, and 113 GWh of electricity have gone missing since January. That’s the annual consumption of about 10,000 homes.

This unaccounted-for gap in electricity supply and demand has slightly unbalanced the whole European grid, lowering the frequency, like a leaky pipe lowering the water pressure.

The lower frequency of the European grid means that the seconds have been dragging out noticeably longer for loads of clocks, putting them almost 6 minutes out of whack.
.
.
.
.
.
.
.
.
.
.
.
.
.
…and that’s why I was late.

any idea exactly what's going on with Kosovo and Serbia's energy to make this happen? None of the coverage I saw had much more info than the @ENTSO_E press release: entsoe.eu/news-events/an…

also FAO @SamJamesMorgan – someone has to get to the bottom of this!

Someone buy me a massive printed map of the European electrical grid, please! entsoe.eu/publications/o…

UPDATE: It seems to have been solved. No more excuses for being late for work, cats and kittens.

entsoe.eu/news-events/an…