Declaring a national disaster would unlock additional funds and resources to "better manage the crisis," Fikile Mbalula told a news conference after the party's new executive committee met over the weekend.
The years-long crisis of intermittent power cuts has worsened in recent months, with the electricity network operated by the debt-laden state energy firm Eskom failing to keep pace with demand as it struggles to maintain its ageing coal-powered infrastructure.
"We shouldn't be arrogant and deny the fact that we have... a crisis," Mbalula told a news conference.
"We are responding to this crisis, and the president and the team in government have been given a clear instruction by the ANC," he said.
He said the move would speed up the response of President Cyril Ramaphosa's administration, with a target of ending the blackouts by year-end.
The scheduled blackouts, which can last from two hours to over 12 hours a day, have sparked widespread anger and taken a heavy toll on industrial production and businesses.
Opposition parties have vowed to stage more protests against the government's response to the blackouts, after the most recent mass demonstrations last week drew several thousands of people into the streets.
South Africa's economic growth is expected to slow to just 0.3 percent this year because of the power shortages, after growth of 2.5 percent last year.