Elon Musk’s agreement to build the world’s largest battery for South Australia isn’t just an extraordinary technological breakthrough that signs coal’s death warrant. It’s potentially a game changer in the way we do politics, reinserting the importance of basic reality into a debate which has been bereft of it for too long.

There’s been a lot written in recent years on the idea that we are living in a “post-truth” world. Climate writer David Roberts brought it to my attention around 2010, when I was grappling with the idea that dinosaur politicians and rent-seeking corporates not only weren’t telling the truth about climate change and energy: they were actively dismissive and destructive of the very idea of truth.

While we got a taste for it in Australia under Tony “don’t believe anything I haven’t written down” Abbott’s government, the idea sprang into the global mainstream last year with Donald Trump’s election campaign and the Brexit bus.

It seemed that truth no longer mattered. Facts were not just unimportant, but barriers to be smashed through with rhetoric. Demonstrating beyond reasonable doubt that a politician was lying no longer had any impact. Even when people agreed that he (usually) was lying, they still supported him, because he activated a frame or a value that drove their political decision-making.

At the same time, political scientist Brendan Nyhan conducted fascinating and depressing research on what he called the “backfire effect”. Although this research isn’t conclusive, he showed that using facts to try to reverse strongly held political views – such as on climate change, vaccination, gun control – was worse than useless, generally ending up emphasising existing views rather than altering them. He also showed that these tribally-based political views trumped (and I use that word advisedly) our ability to do maths. We can read graphs really well. Except when they contradict our political views. Nyhan showed a clear tendency for people with high numeracy skills to misread graphs about gun control or climate change, even when they’d just correctly read the same graph about soap.

What’s this got to do with Elon Musk’s great big battery?

Often politics deals in ephemeral ideas, subjective ideas, ideas about how well off we are, how confident we might be about the future, how safe we feel. Decades of political focus on the dismal science of economics has enabled this. Politics can become a confidence game.

But sometimes politics comes up hard against reality.

For months now, Malcolm Turnbull, Josh Frydenberg, various fossil fuel energy executives and media commentators like Paul Kelly have been rabbiting on about the “energy trilemma”. It’s their contention that energy policy must deal with cost, reliability and emissions, and that it is impossible to achieve all three at the same time. Conveniently, they choose to put emissions at the bottom of this list and bury it under a pile of coal, which they claim is cheap and reliable.

This is not true. Not even close to it. It doesn’t stand up to basic scrutiny.

Renewable energy, which obviously wins on emissions, is now beating coal on cost. What’s more, with an energy grid managed effectively by people who want renewables to succeed, it is no less reliable than fossil fuels. The fact that arch-conservative, Cory Bernardi, was recently revealed to have installed rooftop solar panels demonstrates that these people do not even believe their own rhetoric. They have just chosen to throw truth onto the fire of climate change for political reasons.

Interestingly, the great bulk of Australians already don’t believe this story. The Climate Institute’s latest (and sadly final) Climate of the Nation report, featuring comprehensive polling data on a range of climate-related issues, showed once again that the vast majority of Australians want to see more renewable energy, do not believe that renewable energy is driving price rises (correctly identifying mis-regulation, privatisation and other corporate price-gouging as more to blame), and don’t think renewables need fossil fuels to back them up in the long term.

The politicians, business people and commentators, however, continue to lie. It suits their agenda, and it clearly activates something in people’s minds – enough to make it worth their while. People know that they are wrong. But they sound like they might sort of be right.

Musk’s gambit closes this book. He has brought reality crashing in.

Within 100 days, there will be a huge battery system making South Australia’s energy grid clean, affordable and reliable, and benefitting the eastern states along with it.

All the talk of building new coal-fired power stations, or a Snowy Hydro 2.0, no longer sounds vaguely “truthy”. It sounds ridiculous. It sounds silly. It sounds like old men yelling at clouds.

This won’t suddenly bring back a cherished (and somewhat mythological) era of truth in politics. But it will have a real, demonstrable impact. It will help. We all owe deep gratitude to those who have made it happen.