He also reportedly backed Bill Shorten's comments about Coalition MPs who support the construction of new coal-fired power stations as being "knuckle draggers", according to a report in The Australian.
Conroy reportedly said Labor's proposed 50% renewable energy target was popular with many of his coal worker constituents because many of them "have solar panels on their roofs".
"Renewable energy is as popular in my region as it is anywhere else in the country," Conroy said.
"I'm saying to people that when our existing coal-fired power stations reach the end of their useful life, and some of them already have, then they will be replaced, absent a subsidy by government, with renewable energy backed up by gas or pumped hydro storage.
"That is what I tell miners, that is what I tell people in the industry because it is the truth.
"The weakest and most spineless thing you can do is lie to constituents and say that we can keep going on the way we are going and mislead people, which is what Tony Abbott and Matt Canavan and all that crew are saying."
Coal-fired power stations in the Hunter Valley include AGL's Liddell and Bayswater stations and Origin Energy's Eraring, which are all scheduled to close by the mid-2030s.
Attempts by the federal government to get AGL to extend the life of the Liddell power station failed, forcing the government to look at alternatives to providing base load power from coal-fired generators after 2022.
Several Coalition MPs are calling for the federal government to subsidise the construction of a coal fired plant to make up the shortfall.