Johannesburg - Numsa agreed on Wednesday with Minister in the Presidency Trevor Manuel’s pronouncements that the proposed electricity hikes "were unacceptable".
"We welcome Minister Manuel’s firm stance on this ridiculous request by Eskom," the National Union of Metalworkers of SA (Numsa) said in a statement.
"We have argued strongly that these electricity tariffs will plunge our economy into a deeper crisis, and will result in massive job losses," it said.
Manuel warned against energy tariff increases during a briefing on the National Development Plan in Cape Town on Tuesday.
He said rapid increases in administered prices, including energy, had to be guarded against.
Numsa said the National Energy Regulator of SA should grant Eskom a "single digit, inflation-related increase" for a period of three years.
Nersa held public hearings into the proposed tariff increases earlier this month.
Eskom has asked for a 16% increase in electricity prices for each of the next five years.
Numsa said this would impose a heavy burden on households and consumers, especially the poor.
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