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Tárrases gets more than half it's electricity from its neighbor (and awkward love-hate pseudo-feudal master), Mahhal. Mahhal generates a vast proportion of its electricity using geothermal, but also burns coal and conventional fuel oil (diesal). It has some reserves of coal but imports petroleum.
Tárrases has no native resources for power generation, though there have been plans to develop a geothermal site somewhere on the island in cooperation with Mahhal Electric. There is a high voltage underwater cable from Mahhal's island of Tteu, which ties Tárrases to the Mahhalian grid. And the island has a diesel electric generating plant next to the small refinery at Espadas y Cascos. The island's main trunks run north to south, with the part between the Bulevar Eddison substation and the Serpiente Ascendente substation being underground, and the remainder being high tension aboveground lines.
Red eléctrica en Tárrases
With High Voltage underwater connection across the channel to Tteu.
The power plant and refinery
Located on the Bahía Soapacwi, with a pipeline landing pier for oil tankers.
Bulevar Eddison substation
Conversion from the underground trunk at the southern end.
Serpiente Ascendente substation
Conversion from the underground trunk at the northern end.
Terminal del Estoque substation
This is where the HV underwater cables from Mahhal come to land.
A substation in the downtown area, at Espada de Bronce / Zona Roja
All those neon signs in the red-light and gambling districts need lots of electricity. Also conveniently next to the Tarrélectrica management offices. The cables are of course all underground, here, and don't show on the map. But they're there - I've mapped them out.
Wind at Escondite de Piratas
The offshore island of Escondite de Piratas is self-sufficient with wind power.
Small hydro at Torreblanca
There is a very small-capacity hydroelectric generating facility on the main water reservoir at Torreblanca.