The trade union said since the power sector was handed over to private operators, no significant improvement has been recorded.
The Nigerian Labour Congress (NLC) has called for the reversal of private ownership and control of the electricity sector.
The trade union also kicked against the privatisation of water resources as proposed in the National Water Resources bill currently before the National assembly.
The union stated its positions during a meeting at the National Union of Electricity Employees (NUEE) in Yaba area of Lagos on Tuesday.
The National Water Resources bill which was introduced in the 8th Assembly was reintroduced in June.
The bill had caused outrage among many Nigerians who perceived it as a power grab by the federal government.
Electricity
Private operators took over Nigeria's power sector from the Power Holding Company of Nigeria (PHCN) in 2013.
The privatisation of the power sector was meant to break the control of electricity generation and distribution by the government, to ensure adequate, regular and stable supply of electricity to consumers at a reasonable cost.
NLC
Joe Ajaero, the union's national deputy president, said that since the handover of the assets to private owners, corruption and inefficiency had remained in the sector.
He said Nigerians are being made to pay for darkness.
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Also, the president of NUEE, Martin Uzoegwu, said that despite the privatisation of the power sector, no significant improvement has been recorded in the past nine years.
Speaking to journalists after the event, he said the power sector has been erratic. He described the change of ownership as a "scam."
Mr Uzoegwu said the government has spent trillions of Naira in "the same sector that they privatised. That is corruption."
"The government should look at it and revisit it and let us deprivatise it. Let it go back to the public."
The NUEE leader further said "we need to talk about promoting transparency in the sector."
Speaking on the water bill, Philips Jakpor from the Corporate Accountability and Public Participation Africa (CAPPA) organisation, stressed that access to water and electricity are human rights.
He told the labour members at the event how they held meetings to stop the passage of the water bill.
Mr Jakpor noted that for the campaign to stop the passage of the bill, they "recruited opinion leaders, community leaders, labour, civil society" and others.
He added that to a " large extent" the campaign stalled the proposed law.
