"Barseback is going to close as has been planned tomorrow," said Lars Andersson, spokesman for the Ministry of Sustainable Development.

A package of measure to increase energy from renewable sources to replace the capacity lost through the closure of Barseback 1 and 2 had already been completed, he added.

Sweden's decision to phase out nuclear power in a referendum in 1980 came at the height of anti-nuclear protest and a first reactor, Barseback-1, was closed in 1999.

However, with growing worries about global warming and the need to reduce carbon dioxide emissions to meet stricter global standards, opposition to nuclear power has been losing momentum.

Sweden's neighbour Finland is building its fifth reactor, which is to come on line in 2009.

Critics also question whether enough has been done to fully replace output from Barseback.

"There is a lack of electricity in the Nordic market and this will only contribute to that," said Kalle Lindholm, spokesman for Sweden's power industry group Swedenergy, adding that the shortfall was around 15 terrawatt hours annually.

Nordic power prices have already factored in the loss of capacity at Barseback. However, analysts said spot prices might be affected at times of high demand, for example in the coldest periods of the year.

"In a very cold situation, for example in January, it could absolutely have an effect on prices," said Ole Tom Djupskaas, head of the Nordic power group at research firm Point Carbon.

"And in the longer term this will have an effect because consumption is gradually increasing and production decreasing."

RENEWABLES

Swedish industry has already responded to high energy prices and the decision to close Barseback, which produced around 4 terrawatt hours of electricty out of Sweden's total 148 terrawatts in 2004 and a Nordic power market of 390 terrawatts.

A group of the country's biggest industrial concerns, such as smelter and miner Boliden have launched their own energy buyer called Basel, which aims to make up the shortfall in electricity.

The Swedish government wants the power industry to focus on renewable energy sources.

State-owned Vattenfall, Europe's fifth biggest power producer and with Sydkraft one of Barseback's owners, said in November it would invest 1.5 billion crowns ($217.9 million) in the construction of an offshore wind power park in the Oresund sound near the bridge between southern Sweden and Denmark.

However, energy supply from wind power can fluctuate depending on the weather and some do not see it as a reliable alternative to nuclear power.

Critics say that closing Barseback goes against the government's policy of promoting environmentally friendly energy as the shortfall will have to be made up by importing energy produced from fossil fuel power stations.

"It will increase carbon dioxide emissions," said Swedenergy's Linholm.