Second interconnector set to ‘complement’ renewable energy generation

Why did Malta not invest in more renewable energy generation, instead of a second electricity interconnector to Sicily, which also relies on the importation of non-renewable sources?

A project statement by the Maltese government says the interconnector will not exclude future investment in renewables to complement energy generation.

The development of a second interconnector linking Magħtab in Malta to Ragusa in Sicily, will back up any future investments in offshore wind or solar farms by making up for the intermittency in energy output of renewable energy sources.

The statement, presented by the government-owned Interconnect Malta company, says the Malta will be importing the energy required to power both its expected economic growth, and the electrification of road transport.

Indeed, gross energy consumption is expected to increase from the current 2,500 GigaWatt hours, to around 3,800GWh in 2040.

But currently, only 14% of the energy imported through the first interconnector comes from renewable energy sources.

The decision to go for a second interconnector, instead of investing in the local generation of renewable energy, was criticised by Green Party ADPD because the interconnector will only shift emissions elsewhere.

According to Interconnect Malta’s project statement to the Environment and Resources Authority, which forms part of an environmental impact assessment process, the second interconnector will facilitate the integration of any potential offshore solar or wind farms, with a stable connection to the national grid, offsetting the intermittency of renewable sources.

This is because renewable energy cannot always consistently produce energy at all hours of the day.

Interconnect Malta considers a number of alternatives before concluding that a second interconnector is a better alternative. One of the options is of investing in additional renewable energy generation, acknowledging this would meet the objectives of the European Green New Deal. But due to the intermittency of these sources, Malta would still need an additional supply of energy, the report claims.

The need for energy storage systems for such renewable sources would also be “challenging”, while renewable energy plants would need a larger area than that required by conventional generation plants or interconnectors.

“As such an area is not available onshore in Malta, offshore solutions will have to be resorted to. Such infrastructure will result in increased capital cost,” Interconnect Malta said.

But while noting these challenges, the report concludes that renewables and the interconnection cable “are complementary, and one will not exclude the other”.

The second interconnector can also operate in a bi-directional mode, importing electricity from Sicily but technically able to transmit excess electricity produced in Malta back to Sicily.

Another option considered was the development of an additional power station. But any such plant would have to be hydrogen-ready in order to comply with reduced greenhouse emission limits mandated by the European Green Deal.

And such technology is “not mature enough” and is still considered a “risky proposition”, even if this technology is expected to evolve rapidly in the future. Investing in such a technology prematurely could result in “stranded assets”, Interconnect Malta said.

One of the risks of importing more energy from the interconnector is that the Maltese grid could be more exposed to fluctuations in the Sicilian grid, which may destabilize or disrupt normal service.

But the report states that experience with the first interconnector has shown that such “situations are infrequent, and the protection systems installed protect the Maltese grid to a large degree.”

The report also justifies the choice of Magħtab, which hosts the present interconnector, as the site for the new terminal station.  The only other site considered was the Delimara power station, which is already generating 630MW of energy.

Adding another 200MW power at this site and leaving the Magħtab terminal station importing only 200MW would have reduced the benefit of the project from the point of view of security of supply, in the case of any unwarranted event at Delimara. Therefore, connecting the project at Magħtab would lead to a more reliable system, as the energy inputs to the Maltese grid between these two sites would be further equalized.

Moreover the terminal station at Magħtab is already equipped with most of the civil works needed to install the second interconnector, namely the HV switchgear room, cable ducts, a transformer bay as the cable tunnels to connect this station to the local electricity grid.

With the exception of equipment installed in terminal stations already used for the first interconnector in Ragusa and Magħtab, the project will be entirely underground or underwater and no permanent above-ground constructions will take place in Malta.

The length of the submarine cable is estimated to be between 97km to 102km, depending on the final route chosen. The onshore cable is estimated to be between 0.8km and 2km in Malta and between 17.9km and 20.1km in Italy. Onshore equipment shall be limited to electrical equipment installed, in the existing Magħtab terminal.