Slovenians will head to the polls on 24 November to cast their vote in a consultative referendum on the construction of a new unit at the Krško nuclear power station, a decision endorsed in a bi-partisan vote at the National Assembly on 10 October.

All parties bar the junior coalition Left, a single MP of the senior coalition party Freedom Movement and an independent MP who defected from that party voted in favour of the referendum motion.

The government and the opposition say Slovenia should rely on a combination of nuclear and renewables for a stable supply in the transition away from fossil fuels. Expansion of nuclear capacities is seen as the most important long-term measure in the process.

They say the popular vote will not decide on a final decision on a new reactor but on whether to give the government and the investor a mandate to continue their work on preparing the project, indicating another referendum may be called later.

Final decision still some years away

Prime Minister Robert Golob says the final decision about the construction may be adopted in 2027 or 2028.

Before that, Slovenia will need to invest over €100 million in research and human resources, therefore it is important to know whether the public finds a new nuclear reactor realistic, he told a discussion on nuclear energy he hosted the day before the vote in parliament and which also featured Rafael Mariano Grossi, director-general of the International Atomic Energy Agency (IAEA).

Minister of Environment, Climate and Energy Bojan Kumer said that under an optimistic scenario, a final decision about Krško 2 could be made in five years, the building permit would take another four years, while construction would take seven years.

Issues raised by NGOs

The opponents, including a number of non-governmental organisations and environmental campaigners, argue the referendum is premature as there is not enough information for voters to make an informed decision, and would give the government a carte-blanche for the project.

They are also unhappy with the referendum question where the voters will be asked whether they "support the implementation of the Krško 2 project, which will ensure a stable supply of electricity together with other low-carbon sources".

A number of NGOs described the question as "suggestive and manipulative", arguing voters should be offered several scenarios of the country's energy future to chose from, including a non-nuclear one.

Danijel Levičar, the state secretary in the prime minister's office in charge of the national nuclear programme, rejected the notion that the referendum outcome would issue a "carte blanche" for the project itself. He says the investor and government need a mandate to prepare the paperwork, select a supplier, obtain a licence for the location, provide the staff and to start the siting process.

He argues enough data is available for the voters to make an informed choice. "If we decide we do not want the project we should do that as soon as possible," he told MPs. He estimates the preparatory activities will cost between €100 and €150 million.

The state-owned energy company Gen Energija, which owns the Slovenian half of the Krško nuclear power station (Croatia owns the other half) has valued Krško 2 project at between €9.3 billion and €15.4 billion, depending of whether capacity is 1,000 or 1,650 megawatts.

Support from businesses

Nuclear energy expansion enjoys strong support from businesses with a group of prominent entrepreneurs proposing that businesses from Slovenia and neighbouring countries take part as investors in exchange for fixed energy prices over the long term.

Igor Akrapovič, the boss and owner of exhaust maker Akrapovič, believes about €2.5 billion could be raised in such a way. Meanwhile, Gen Energija estimates it could raise 20-30% in own funds along with the other players in the energy sector.

Visiting the country, IAEA director-general Mariano Grossi said Slovenia can be proud of its nuclear programme and should use its experience in deciding about future use of nuclear power.

He sees the Krško power station as Slovenia's advantage over other countries who are only now starting to consider the use of nuclear.

However, one of the concerns raised by environmentalists is that the final cost of the new reactor could be much higher than planned, also because of experience of other countries building such projects.

They likened Krško 2 to the controversial unit 6 of the coal-fuelled Šoštanj thermal power station, whose price tag ballooned from the initial €600 million in 2006 to €1.4 billion at the end of 2013, while the plant has been generating power at a loss and is now set to be wound down years earlier than initially planned.