Live data from Hacker News

Baltic countries disconnect from the Russian power grid

baltic-grid.sympower.net

41–50 of 70 posts

Re: Baltic countries disconnect from the Russian power grid

#41
The "Map of European Transmission System Operators" at the top of this page shows relevant geographical context:

https://en.wikipedia.org/wiki/Synchronous_grid_of_Continenta...

Note how Denmark is split between two separate synchronous grids.

There are lots of high-voltage DC connections between the grids in this map.

Re: Baltic countries disconnect from the Russian power grid

#42
post #19
post #9

What does it actually mean to disconnect? Is there some physical connection being broken? How is that done?

Yes it's some physical connection being broken. It's not unusual to adjust the ways in which the electrical grid is connected. See https://www.youtube.com/watch?v=7Q-aVBv7PWM from Practical Engineering which talks about some of the nuances of building switches which can break connections between different parts of the grid safely.

[deleted]

Re: Baltic countries disconnect from the Russian power grid

#43
post #25

Earlier quoted context omitted.

Off-topic; Why does America use 60Hz? I've never found a satisfactory answer.

> They were disposed to adopt 50 cycles, but American arc light carbons then available commercially did not give good results at that frequency and this was an important feature which led them to go higher "The origins of 60-Hz as a power frequency" https://ieeexplore.ieee.org/document/628099 Better question is why did Germans pick 50 Hz, I'm not aware of any comparable benefits of having lower frequency

If I read your source correctly, there is no real advantage of 60 Hertz or 50 Hertz, and the decision was usually due to circumstantial reasons, like supporting some existing arc-lights or difficulties with induction motors. Induction motors are also the reason why some railways chose to use 16⅔ Hertz, still in use to this day.

In the end, there is no real difference between 50 or 60 Hz, there is no clear advantage to either, especially with modern components. But you do have to choose as the whole network is synchronous.

Re: Baltic countries disconnect from the Russian power grid

#44
post #22

The interesting bit is that this includes Kaliningrad. See: https://www.kyivpost.com/post/46628

Very cool! I couldn't tell from the article if Kaliningrad will remain on a grid with the Baltics or become its own island.

Kaliningrad will become its own island.

Re: Baltic countries disconnect from the Russian power grid

#45
post #2

On Saturday (8th of Feb), Baltic countries will disconnect from the Russian power grid and synchronise with the Continental European electricity system. They will operate in "island mode" for 33 hours, and then synchronize with the European grid frequency. The frequency is a key parameter of the grid. If there is too much load, it goes down, and if there is too much production it goes up. A lot of critical grid infra…

Surprised this isn’t already available. Does Estonia only publish 5 minute frequency data?

Re: Baltic countries disconnect from the Russian power grid

#46
post #12

Earlier quoted context omitted.

A better question is why does Japan use Both 60 Hz and 50 Hz in different areas? And that’s really just a legacy from early decisions at different companies when the grid was first introduced, and there’s never been a sufficiently compelling reason for either to swap. 60 Hz is slightly better in terms of flickering, but neither has enough advantages to really be a determining factor on their own.

US did the same, Southern California was 50 Hz at first. It didn't convert until after WWII

There was 25 Hz infrastructure in Ontario until the 1950s

https://www.lifebynumbers.ca/history/the-rise-and-fall-of-25...

Re: Baltic countries disconnect from the Russian power grid

#47
post #36

Earlier quoted context omitted.

It's possible to transfer power between two grids at different frequencies (even between 50 and 60 Hz), it just requires more expensive equipment.

There's by now a lot of DC links in Europe for example going from the European continental grid to the Nordic grid. Denmark is split between the two so it has a country internal DC link too.

There are several DC links in Canada too, i.e. the underwater link between the Lower Mainland of British Columbia and Vancouver Island, which uses only one conductor and the water itself as the other. The North American grid is also DC linked betwen Alberta and Saskatchewan at one point.

DC links solve a myriad of synchronization problems.

Re: Baltic countries disconnect from the Russian power grid

#48
post #6

Earlier quoted context omitted.

This would require both grids to be exactly synchronized.

It's possible to transfer power between two grids at different frequencies (even between 50 and 60 Hz), it just requires more expensive equipment.

At one site in a jungle, my employer had an electrically driven flywheel built that ran on that country's mains grid, paired with an AC alternator on the flywheel that fed the building. This solved a variety of frequency and voltage problems, including mains outages. If the mains went dark, a diesel generator would kick in to boost the flywheel RPMs on an as-needed basis rather than constantly run.

Re: Baltic countries disconnect from the Russian power grid

#49

Earlier quoted context omitted.

US did the same, Southern California was 50 Hz at first. It didn't convert until after WWII

There was 25 Hz infrastructure in Ontario until the 1950s https://www.lifebynumbers.ca/history/the-rise-and-fall-of-25...

Yep, the government had to go house-by-house, building-by-building replacing all electrically powered devices that could not be adapted. Thankfully it also happened early in the era of electronic devices.

Re: Baltic countries disconnect from the Russian power grid

#50
post #25

Earlier quoted context omitted.

Off-topic; Why does America use 60Hz? I've never found a satisfactory answer.

> They were disposed to adopt 50 cycles, but American arc light carbons then available commercially did not give good results at that frequency and this was an important feature which led them to go higher "The origins of 60-Hz as a power frequency" https://ieeexplore.ieee.org/document/628099 Better question is why did Germans pick 50 Hz, I'm not aware of any comparable benefits of having lower frequency

50 Hz is a lot easier to math (50 Hz = 0.02/s, 60 Hz = 0.0166666). Don't know if that's why, but it very easily could be.
Post reply on HN