Last week, ADMIE signed the contracts for the 1st phase of the Cyclades interconnection Project, consisting in 150 kV AC three-phase sea cable from the mainland to Syros island, and from there to Mykonos, Paros and Tinos (see the picture below).
The business case for the interconnection project is impressive. We are talking about an investment of roughly 232 M€ that will save approximately 100 M€ per year, and will avoid the emissions from fuel fired power plants in the islands, increasing the reliability of the grid and the power quality.
Why are interconnections important for the sustainability of the grids?
First, more interconnected systems increase reliability. This is specially the case for islands, as keeping stability in an island grid is more difficult compared to managing a grid of greater size with more power generation facilities online, as back-up, and a meshed grid. That is more socially sustainable than a grid with frequent outages.
Second, because interconnections increase the geographical dispersion of renewable generation, flattening the supply of renewable power, and enabling increased penetration of renewable energy that can be consumed, where produced or along the interconnection. If local polluting diesel stations can be shut down, as in the Cyclades, benefits are social (health), economical (tourism) and ecological. This means sustainability on the three domains.
And third, it makes perfect economic sense, as the power supplied from interconnected systems will have more competition due to an increase in the supply market, the resulting price is lower. The prices of two interconnected systems tend to become closer as the interconnection increases capacity.
I already wrote about islands as being the first stop to 100% renewable. However, if there is a possibility to interconnect an island, the benefit-to-cost ratio of the interconnection is better than transitioning to 100% renewable in isolation. But it also facilitates the subsequent transition to renewable, that need no longer have local storage if the power can be exchanged with a main grid.
In short, if there is a possible interconnection, first interconnect the grid, and then move to renewable. In fact, such islands, have the opportunity to transition to 100% renewable in transportation as well, if it is electrified, not only for vehicles, but in the near future for boats and ships with shore-to-ship connections. The case for vehicles is beneficial for storage, as I commented on battery energy storage, decarbonizing transport and V2H.
We’ll see soon which island reaches first 100% renewable transportation, heating and electrical…