After years of importing more energy than it exported, Portugal in 2016 exported €200 million more than it imported, last year exported a net €140.75 million, according to the statement.

It quotes Sanches as saying that the growth in net exports of electrical energy reflect Portugal's investment in renewable energy generation.

In turn, it adds, "the increase in production from renewable sources has also been a determining factor in the drop in wholesale electricity prices in the Iberian market (Mibel) and in the operation of the respective Iberian systems in recent years."

It also cites moves to increase cross-border linkages as another "key piece" in the government's strategy for the sector, "with a view to the sustainability of the national electricity system and the reduction of the tariffs of families and companies."

The "next big challenge", it goes on to say, is the reinforcement of cross-border links between Iberia and other European Union countries, via France, under the EU 'Clean Energy' legislative package that is currently being debated in the European Parliament.