Posted By: gfretwell
HVDC Greece to Crete - 08/03/20 12:11 AM
Is anyone working on this? I was reading on one of my other groups that they are running a couple of underwater DCHV cables under the sea between Greece and Crete., Sounds like quite a project. It is supposed to replace 3 bunker oil plants. I am not sure how Greece will be producing the power tho. Anything has to be better than oil.
Posted By: gfretwell
Re: HVDC Greece to Crete - 08/06/20 06:28 AM
Dimitris Tzortzakakis Got back to me. This is awesome
This is the thread so far
>> A few weeks ago the contracts were signed for this connection, from
>> Crete, to Attica, 2 underwater cables, length 500 km, 500 kV, HVDC.It
>> goes without saying that the inhabitants of the Damasta village, don't
>> want the conversion station being built in their village ("not in my
>> backyard").Not to consider the repercussions both in economy and in
>> stability for Greece and Crete, 3 power stations using mainly mazut,
>> almost 1,000,000 tons of heavy fuel annually, not to mention the
>> pollution.The "small"cable, 2X180 km, 150 kV three phase, from Crete to
>> Peloponnissos, is going to be energized later this fall. 200 MW.The
>> "large" one-800 MW.The small one-the longest AC underwater link
>> globally, also the large one. When both of them are energized, the
>> savings willl be in the range of 100,000,000 euros annually for the
>> state utility clients all over Greece-all greeks are paying so we
>> Cretans don't have more expensive electricity.
> HVDC? That must involve some huge inverters but I guess the capacitive
> losses you avoid make up for it. Sounds like a very interesting
> project. I would think a passive conversion plant would be preferable
> to three bunker oil plants but I guess it depends on who's yard it is
yeah that's exactly whei I thought, Damasta is only a small village, and
there will be no pollution from the conversion station, while the
Linoperamata power station is only 15 km from Iraklion, the city I live,
with 180,000 inhabitants, running 6 steam units, 4 2-stroke diesels and
numerous gas turbines. The 1st unit is 6 MW and built in 1966 and is
still running! On a clear day from the mountains you can see the smog
from the aforesaid power station hanging over Iraklion. The other one in
Xylokamara, Chania is again near the city of Chania, but is running
mainly a combined cycle gas turbine and some open cycle gas turbines so
only diesel fuel. The newest one is in Atherinolakkos a desolate area
and is running 2 60 MW 2-stroke-diesels and 2 60 MW steam units.
About the cable-the other option would be AC, 400 kV, 3-phase but the
capacitive losses would be colossal, over 500 km. The "valve hall" is
going to be as large as one of our current power stations with
transistors big as a room and totally inaccesible when running. There is
going to be another valve hall near Athens and KYT Koymoyndoyroy (Center
of Extra High Voltage-directly from the 400 kV rails I suppose). This is
going to be a twin cable, with 1000 A current and as thick as 6
feet!With the insulation for 500 kV and shielding strong enough for the
bottom of the Aegean Sea, as deep as 2500 meters-almost as high as
Crete's highest peak, psiloritis.
Posted By: Trumpy
Re: HVDC Greece to Crete - 09/08/20 08:04 AM
Why would you not want a power upgrade like this?
Especially to negate the burning of fossil-fuels.
New Zealand has a system like this, run mainly overhead from Benmore hydro dam in Otago under Cook Strait with 500kVDC, the total length is 610km.
3 power stations using mainly mazut
The station at Benmore here is miles away from anything, it had a LARGE rectifier bank in it, I visited it during my apprenticeship training as a Liney, it had a large buzzing sound before you even get near the place.
That was back in the days of LARGE Mercury Arc rectifiers, they are all solid-state these days.
I have also seen the other end of it at Haywards, west of Wellington, where the 3 (5) cables exit Cook Strait and head into an Inverter bank, nitrogen transmission system and switching station, there is no noise at all from the inverter banks, apart from the steady fans that keep the heatsinks cool.