Out of the ashes of repeated failed attempts to give us cleaner and more reliable electricity – the emissions trading scheme, the emissions intensity scheme, and the clean energy target – has come something surprisingly good.

The national energy guarantee will do more or less what each of the other schemes would have done. It will make the electricity system cleaner (in accordance with the Abbott government's commitments under the Paris climate agreement) while giving investors the certainty they need to work out what kind of power stations to build and when.

Because most of the other schemes were never implemented and the one that was (the renewable energy target) wasn't made permanent, investors have been denied that certainty until now.

Chloe Munro was a member of the Finkel review into the future security of the national electricity market. She told a conference in Melbourne last week that merely having a scheme, any sort of scheme that could withstand repeated electoral cycles, would be enough to give investors the confidence to spend the billions of dollars needed to build plants likely to last as long as half a century. With no national scheme (apart from the renewable energy target, which ends from 2020) they've had to guess what the future schemes will require of them. The details of the scheme adopted weren't as important as knowing it was there.