'Big advocates' of renewables have now 'come to understand' the limits of them

Activist and author Michael Shellenberger says many people who used to be "big advocates" of renewables came to understand the limits of them.

"We now understand that we need nuclear power," Mr Shellenberger told Sky News Australia.

Mr Shellenberger said he was "absolutely" opposed to nuclear energy in the past.

"I was raised to be anti-nuclear."

However, Mr Shellenberger said, "the truth is that we could produce all of our energy from nuclear right now".

"There’s always a period of time where people need to get accustomed to the new technology.

"The main obstacle is really psychological - it’s ideological, political obstacle - the existing technology is really quite good.

"We’ve been using it for over 60 years."

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