Lights out: understanding the power outages dogging this festive season

EXPLAINER | With four electricity outages in December, one of them a major nationwide blackout, we try to understand why this is happening in 2019

The two gas-fired plants at Delimara alone are not enough to meet December's peak demand
The two gas-fired plants at Delimara alone are not enough to meet December's peak demand

Just two years ago the newly built gas power station was commissioned and started supplying electricity to the grid.

The 200MW plant built and operated by Electrogas, a private consortium, took Enemalta’s maximum supply capacity to over 700MW.

The new plant came with its fair share of controversy, not least because of the alleged corruption involved in the award of the tender – it transpired that one of the shareholders, Tumas magnate Yorgen Fenech, had a secret company called 17 Black in Dubai, which was a target client of the Panama companies set up by then energy minister Konrad Mizzi and the Prime Minister’s former chief of staff Keith Schembri.

Fenech now stands charged with having commissioned the murder of Daphne Caruana Galizia, who had outed the existence of 17 Black.

But on a different level, some exponents of the Nationalist Party had also criticised the new plant as unnecessary, given the commissioning some years back of the interconnector with Sicily.

The government’s argument has always been that Malta could not depend solely on imported electricity and had to have sources of generation on the island. The new power station would ensure security of supply, while enabling the company to dismantle the aged Delimara power plant (the big chimney, which has since been demolished) that faced an imminent EU closure deadline.

This is the context within which the December electricity outages have to be understood.

In the absence of clear information from Enemalta, MaltaToday tries to understand why the country is grappling with major electricity cuts despite the multi-million euro investments of recent years.

Electricity cuts have plagued the festive season
Electricity cuts have plagued the festive season

What happened on 23 December?

At around 7.30am, Malta was hit by a nationwide power-cut. Enemalta later explained that the power outage was a result of damage to the subsea interconnector between Sicily and Malta that was being used at full potential at the time. The sudden loss of 200MW, which is the interconnector’s full capacity, will necessarily trigger an automatic shutdown to the whole system, to avoid further damage. The power-cut lasted several hours in some localities as Enemalta shifted its energy supply to the power plants at Delimara. The company did not explain why the interconnector was being used at full capacity at the time.

READ ALSO: Power-cut was another blow to Christmas shopping, Valletta shop owners say

What happened to the interconnector?

Enemalta said the cable sustained extensive damage in international waters and it would take several weeks to repair. Sources in Italy had told MaltaToday that the cable was damaged by a ship’s anchor. The end result is that Enemalta cannot make use of the interconnector for the foreseeable future.

Does Malta depend on the interconnector to satisfy its electricity demands?

The short answer is yes but not exclusively. The long answer requires a deeper understanding of Enemalta’s energy mix. The company supplies electricity to the grid from three principle sources: the interconnector (200MW), the D4 power plant operated by Electrogas at Delimara (205MW), and the D3 power station (ex BWSC) operated by D3 Power Generation at Delimara (152.8MW). Between them, these three sources can supply a maximum of 557.8MW, which is more than enough to cover Malta’s peak demand in the summer months. But Enemalta also has two old power plants at Delimara that can produce 180MW of electricity. These old plants are operated by Enemalta and run on diesel, unlike the D3 and D4 plants, which run on natural gas. These plants are used as backup.

What is the total electricity supply potential then?

All power sources, including the diesel backup plants, can deliver a maximum of 737.8MW of electricity. Obviously, Enemalta has to contend with maintenance and repair issues that mean some of the sources will not be functioning all the time.

What is Malta’s peak demand?

On 9 July 2019, Enemalta reported its highest ever peak demand at 510MW. Before that, the highest peak was reached in August 2017 when demand topped 488MW. Malta’s peak demand is during the summer months. Figures released by the National Statistics Office last October, showed that the maximum demand in December 2018 was 366MW.

Can the Electrogas and BWSC plants alone satisfy December’s peak demand?

No. Together the Electrogas and BWSC plants produce a maximum of 357.8MW of electricity. For most days, this should suffice (peak demand is not reached every day), presuming that all engines are fully operational and there are no faults or scheduled maintenance. However, given that last year’s peak demand topped 366MW, Enemalta will have to use its own diesel-operated plants to make up for the shortfall and ensure it has enough spare capacity. This is what is happening now after the interconnector was damaged.

If Enemalta uses its backup engines, the shouldn't the demand be more than adequately satisfied?

Yes. The maximum potential of all generating plants at Delimara – D4 (Electrogas), D3 (ex BWSC) and D2 (diesel engines) – runs at 537.8MW, which theoretically is able to satisfy even the summer peak demand. Obviously, there may be some engines out on maintenance or for repair, which means that Enemalta may not have all that spare capacity available. The company has not given a public explanation as to whether all engines at Delimara are working and what spare capacity it currently has available.

So, why are we experiencing frequent power cuts?

In the absence of a proper explanation from Enemalta, the most plausible reason is that the reliance on aged diesel engines to act as sustained backup is proving too much for the machines to handle. However, we also do not know whether the newer plants are functioning at full capacity, which would mean an even bigger reliance on the backup engines. Enemalta’s scant engagement with the public does not help matters. When contacted, a spokesman for the company referred this newspaper to the company's website and Facebook page for updates.

What do we know so far?

Enemalta has lost 200MW from the interconnector pending repairs. The company is relying on its own diesel-powered engines as backup for the two gas-fired plants. In its public explanation of the blackout before Christmas Day, Enemalta warned of unplanned power outages until the interconnector was repaired. In a brief explanation last Friday, after a major power outage hit large swathes of the islands, Enemalta said it had experienced faults in one of the “turbines of the Delimara power station”. It did not specify which power plant suffered a fault. The company has so far failed to explain what caused the widespread power outages on Sunday evening and Monday afternoon even if they did not last long.

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