SACOI 2

Cross BorderOperational300 MW200 kV121 km1992

Basic Information

Also known as:SACOI, SA.CO.I., SA.CO.I.2, Sardinia–Corsica–Italy interconnection, HVDC Italy–Corsica–Sardinia, Sardegna-Corsica-Italia

Status:Operational

Capacity:300 MW

Owners:

Terna S.p.A.

EDF SEI (Électricité de France)

Type:cross border

Website:www.terna.it

Description:

SACOI 2 is a multi‑terminal HVDC interconnection that links mainland Italy (Tuscany/Suvereto) with the islands of Corsica (Lucciana) and Sardinia (Codrongianos). The link uses line‑commutated HVDC technology and, following a 1992 upgrade, is rated at 200 kV DC with a nominal capacity of 300 MW. The original monopolar system (commissioned...

Supply Chain (5)

Project Timeline (1)

1992Commercial Operations Full Power

In 1992, the SACOI interconnection was upgraded with new 300 MW, 200 kV HVDC converter stations at Codrongianos (Sardinia) and Suvereto (Tuscany), equipped with air‑cooled, air‑insulated thyristor valves, replacing the original mercury‑arc converter stations at San Dalmazio and Codrongianos. This upgraded multi‑terminal link, designated SACOI 2 and operating together with the existing Lucciana terminal in Corsica, was commissioned in 1992 and entered full commercial operation at its uprated 300 MW capacity.

Route

	Tuscany	Corsica	Sardinia
Landfall	Salivoli cable landing point (Piombino, Tuscany)	Bastia cable terminal (Bastia, Corsica)	Santa Teresa Gallura landfall (La Marmorata, Sardinia)
Grid Connection	Suvereto substation (380 kV)	Lucciana HVDC converter station (Lucciana)	—

Tuscany

Landfall:Salivoli cable landing point (Piombino, Tuscany)

Grid:Suvereto substation (380 kV)

Corsica

Landfall:Bastia cable terminal (Bastia, Corsica)

Grid:Lucciana HVDC converter station (Lucciana)

Sardinia

Landfall:Santa Teresa Gallura landfall (La Marmorata, Sardinia)

Grid:—

StationCable Route

Financial

€670M€700.5M adj.€19.3k/MW-km

iris.polito.it (Jan 2023)

CAPEX:€670M

Adjusted to 2025¹:€700.5M

Cost Intensity¹:€19.3k per MW-km

Estimate Date:Jan 2023

Source:iris.polito.it

¹ Cost inflated in local currency then converted to euros (where applicable).

Cable Specifications

SACOI 2 Cable 1

Salivoli cable landing point (Piombino, Tuscany) → Bastia cable terminal (Bastia, Corsica)

2 × 200 kV HVDC · monopole · copper 420 mm² · ground return · MI (Mass Impregnated) · 300 MVA · 105 km

System:2 × 200 kV HVDC · monopole

Construction:copper · 420 mm²

Return path:ground return

Insulation:MI (Mass Impregnated)

Power rating:300 MVA

Route length:105 km(105 subsea)

Burial depth:

No project‑specific burial target or uniform burial-depth value for the Suvereto (Italy) → Lucciana (Corsica/France) submarine cable segment of SACOI‑2 was found in the consulted sources. System/project facts that are...

SACOI 2 Cable 2

Santa Teresa Gallura landfall (La Marmorata, Sardinia) → South Corsica (Strait of Bonifacio)

2 × 200 kV HVDC · monopole · copper 420 mm² · ground return · MI (Mass Impregnated) · 300 MVA · 16 km

System:2 × 200 kV HVDC · monopole

Construction:copper · 420 mm²

Return path:ground return

Insulation:MI (Mass Impregnated)

Power rating:300 MVA

Route length:16 km(16 subsea · 0 land)

Burial depth:

Lucciana–Codrongianos is the short Corsica–Sardinia submarine leg of the SACOI system (the Corsica–Sardinia submarine section is reported as ≈16 km in the project literature). The existing SACOI submarine cables are...

Converter Stations

Suvereto HVDC converter station

Suvereto, Italy

LCC · 300 MW 200 kV · onshore

Converter:lcc

Rating:300 MW · 200 kV

Location:onshore

Lucciana HVDC converter station

Lucciana, Corsica, France, France

LCC · 50 MW 200 kV · onshore

Converter:lcc

Rating:50 MW · 200 kV

Location:onshore

Codrongianos HVDC converter station

Codrongianos (Sardinia, Italy), Italy

LCC · 300 MW 200 kV · onshore

Converter:lcc

Rating:300 MW · 200 kV

Location:onshore