Enemalta would not say why it decided to keep relying almost exclusively on the interconnector for its power despite having ample capacity to meet demand through its Delimara plant.

The issue came to the fore on Tuesday, when the Maltese islands suffered two blackouts in the space of a few hours, with Enemalta blaming a fault in the Ragusa terminal in Sicily that affected the interconnector. Enemalta was forced to resort to the Marsa power station, which had been in cold standby for two years.

READ: Interconnector blamed as Malta goes dark

The Minister Within the Office of the Prime Minister, Konrad Mizzi, who handles the government’s energy projects, warned in Parliament that if the problems with the interconnector persisted, Marsa could be used again.

The supply of electricity through the underwater cable linking Malta to the Italian power grid would be kept to a minimum pending the outcome of an internal inquiry after Tuesday’s blackout, Enemalta said.

Replying to questions by the Times of Malta, a spokesman confirmed that at the time of the first blackout, 1.40am, the bulk of the electricity was being supplied from Sicily. It transpired that total demand stood at 190MW, including 132MW being fed directly from the interconnector.

During Tuesday’s blackout, only 13 per cent of the Delimara plant was being used

At the time, the output from the Delimara plant, which has a maximum generation capacity of 444MW, was 58MW, or just 13 per cent. In fact, the spokesman confirmed only Delimara 1, which has been operated since 1992, was in operation at the time.

However, no clear reply was given on the reason why the company kept relying heavily on the interconnector, seemingly against the government policy of not depending on external sources for electricity generation.

“Decisions on electricity generation dispatch are not considered simply on the basis of the available plants’ nominal capacity. Enemalta also considers other technical and operational considerations, such as maintenance requirements, running costs, internal consumption, plant flexibility, emission abatement systems and the duration of start-up procedures,” the spokesman said.

“These considerations, along with other external factors, including industry requirements, weather conditions, time of day and the input of priority-dispatch distributed renewables, are taken into account when planning the country’s day-to-day electricity generation mix,” he pointed out.

The Nationalist Party has long been accusing Enemalta of buying cheap electricity from Italy without passing on the savings to consumers.

As for the reason behind the use of the Marsa plant, Enemalta said its priority was to restore supply as fast as possible. The spokesman noted that this was only possible through its “emergency quick-start open-cycle gas turbines”, one of which was located at Marsa.

However, no reason was given why, in other cases, power was restored without having to resorting to switching Marsa on.

As for the interconnector’s future, Enemalta said it would remain an essential part of the country’s electricity generation mix.

Moreover, with the conversion of the BWSC plant to gas and the introduction of the new Electrogas plant later this year, Enemalta would be decommissioning its older, less-efficient plants powered by heavy fuel oil, the spokesman said. Existing gasoil-fired plants would then be kept for emergency and standby requirements, he added.