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Blackout... of information

After reading many news reports and comments about the latest nationwide power cut, I have a feeling there is still a lot that is not being said.

Almost as soon as the information started coming out, anyone who knows anything about power networks had questions.

Releasing statements over the crucial first 24 hours, Enemalta gave two different stories. The first was rather curious: “The initial outage was caused on Tuesday evening at 1950hrs by a fault at one of the generating units at the Delimara Power Station and an explosion in part of an electricity distribution centre at the Marsa Industrial Estate.”

It is very improbable to have two such faults occurring independently of one another at the same time and it is much more likely that one was the result of the other.

In this case it appears from later statements by Enemalta that the fault – which is really a trip caused to safeguard the power station – was an indirect result of a cable fault at Marsa Industrial Estate.

The question here is that if the fault was on an 11kV cable at Marsa, several safeguards need to be triggered before a trip on a generating unit at Delimara happens, let alone at both power stations.

This is the biggest question of all: why did a fault on an 11kV cable outside the distribution centre cause both power stations to trip and reportedly result in an ‘explosion’ leading to a fire that then caused substantial damage to the distribution centre itself, leaving consumers in the dark for 17 hours? Why did the numerous protection devices not operate to prevent this?

The press conference given by Enemalta CEO Frederick Azzopardi left everyone thinking that the ‘wires’ – which are really quite thick cables – are all deteriorating under our feet.

Public opinion seems to have now been shifted from problems in generation to problems in distribution.

However, the truth is that most nationwide power outages in Malta are the result of cascading trips of generating units, whether these are initiated by faults in generation or in distribution.

Enemalta has always had enough generation capacity to cover Malta’s peak demand with some reserve capacity available for any faults or maintenance. The reason there was a push for investment in generation was twofold, first to keep up with increases in demand and secondly to replace the ageing plant at Marsa, which, although inefficient and polluting, and under heavy fines from the European Union, still supplied Malta with the energy it needed.

Meanwhile, Enemalta also invested a substantial amount in the distribution network.

Over the past 20 years, Enemalta has constructed three massive 132kV distribution centres (at Marsa, Mosta and Kappara) together with five new 33kV distribution centres (at Freeport, Kirkop, Marsascala, Qawra, and San Ġwann). It has invested in tunnels to connect Delimara power station to the main load centres and replaced most of the 33kV and 11kV overhead lines with more reliable underground cables.

Interconnector can be brought back in service more rapidly than generating plant and hence reduce the total duration of an outage

Enemalta also implemented a national control system (SCADA) covering the whole high voltage network and invested €200 million in the new interconnector to Sicily and its terminal station at Magħtab.

The three 33kV distribution centres Mr Azzopardi claimed would be constructed with funds from Shanghai Electric (Manoel Island, Xewkija and St Andrews) were planned years ago and the buildings have already been constructed.

Power cuts happen and this should not surprise us. They happen all around the world and there are times when they are prolonged.

Malta suffers from more of these because it is an isolated island.

Other countries are interconnected through various electricity systems that minimise the impact of trips by facilitating the sharing of resources. With the new interconnector in operation, Malta can expect to reap such benefits too.

While power cuts are a pain, and we would all rather do without them, their effects can be mitigated.

The general public is frustrated when electricity is cut, but what worries most of us is the length of a power cut. Now Enemalta, through its investment in the interconnector to Sicily, had started a project which would reduce drastically the length of time of such events.

The interconnector has a capability of 200MW, which is approximately half the peak demand for all of Malta. In addition, it has been designed with an overload capability of about 85 per cent for one hour.

This means that in case of a trip of generating units, it can provide about 370MW for one hour, which is more than the average needs for Malta throughout the year. This will allow sufficient time for Enemalta to start reserve generating units without resorting to massive load shedding or nationwide blackouts.

Even in the case of a total blackout, which would be very unusual if the interconnector was in operation, the interconnector can be brought back in service more rapidly than generating plant and hence reduce the total duration of an outage.

While it is true that the people who were affected by the lengthy restoration resulting from the damage at Marsa distribution centre would have not been able to enjoy the benefits of the interconnector, it is still worth noting that with the rest of the network fully energised, Enemalta engineers could have focused their energies on getting Marsa South back online and at the same time supplying customers through alternate sources.

Unfortunately the current government seems to be focusing its efforts elsewhere and progress on the interconnector is not being communicated. This project has suffered many delays but the government should not lose sight of how necessary it is for Malta to be connected to the rest of Europe.

If we don’t end our isolation then we will continue suffering huge delays to get the power back on.

No matter how much generation capacity Malta has, if the island remains isolated we will never avoid the possibility of cascading trips and reduce restoration times. This notwithstanding the other benefits such as cheaper electricity and no local emissions.

Rather than writing a cheque to Enemalta to then give to some of the affected consumers, it would be better for all consumers, both residential and commercial, if the government started focusing its full attention on the interconnector and making sure it is completed in the shortest time possible.

Mel Hart is a former communications coordinator at Enemalta Corporation.

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