Elon Musk said Tesla’s energy business will end up as big as its flagship automotive arm, as its Megapack utility-scale battery operation turned profitable.

Tesla launched Megapack last year as its commercial entry to the grid-level storage market, with each unit offering up to 3MWh of storage.

The US group said Megapack was profitable in the second-quarter, with total storage deployments including its smaller Powerwall systems standing at 419MWh.

CEO Musk said: “I think long term, Tesla Energy will be roughly the same size as Tesla Automotive.

“How big is the energy sector? Bigger than automotive.”

Tesla's energy generation and storage arm posted quarterly revenues of $370m, against $5.2bn on the automotive side.

Tesla made a dramatic entry to utility-scale battery storage in 2017, when Musk famously bet by Twitter he could solve the blackout issues in South Australia by co-locating the world's largest battery with a wind farm.

Tesla is also active in home solar systems in the US and Autobidder, an energy management system that’s claimed to aid grid-stabilisation.

Musk said when added storage means the company has a foothold in all the three key pillars of the energy transition.

“You need to have a lot of batteries to store the solar energy, because the wind doesn't always blow and the sun doesn't always shine. So there's like three elements of the sustainable energy future: wind and solar sustainable energy generation; battery storage; and electric transport.”

The Tesla boss added: “I can't emphasise enough. Yes, the battery and solar will both be enormous.”