Steven Marshall’s electricity policy, released this week with a few significant holes, shows how quickly the energy debate has turned.

The differences between the major parties on energy policy can now be measured in degrees – a shrill ideological debate about the value of renewable energy is over and the clean energy proponents have won, at least among South Australia’s major parties.

The parties will continue to campaign fiercely on their respective plans, but when viewed through the prism of policy principle, Marshall’s plan treads similar territory to Jay Weatherill’s.

Both blueprints support storage to add reliability and stability to the state’s renewable energy sources; both will rely on diesel back-up for the next few summers; both continue to depend, to varying degrees, on significant amounts of “dirty” energy from interstate sources.

On that last point, one key difference is that Marshall will devote $200 million to hasten an interconnector with NSW (which will cost a lot more than that).

Strangely, a NSW interconnector was one of the central policies that Labor’s Mike Rann took to the 2002 election (but couldn’t deliver), which kicked off 16 years of Labor rule in South Australia.

Here’s what Marshall said last June: “Labor’s flawed electricity policy led to the closure of the Port Augusta Power Station and now the Weatherill Government is proposing to spend hundreds of millions of taxpayers’ dollars upgrading an interconnector so it can import coal-generated electricity from Victoria.”

His policy’s hat-tip to the concept of “baseload” is to do exactly the same with NSW. The State Government allocated $500,000 in its 2016/17 budget to fund a feasibility study into more interconnection with the eastern states – a study that concluded that it would be more beneficial to have more generation on this side of the border, as Energy Minister Tom Koutsantonis pointed out this week. It’s a point of difference, sure, but the parties, despite their insistence otherwise, are not so far apart even on this issue.

On Weatherill’s state-owned gas power plant, Marshall wants to achieve exactly the same ends as the Premier, but through stimulating private investment rather than spending taxpayers’ money. However, again, in terms of energy policy principles, the parties are almost indistinguishable.

After years of Liberals criticising the penetration of wind power in SA and the planning rules that have spurred the technology’s expansion, the party’s policy now says that “wind and solar now play an important, if challenging, role in South Australia’s energy mix”.

The Liberals, who have been utterly disparaging about the Rann era expansion of wind power, now see it as Mike Rann once did – an economy opportunity. They want to embrace the market to find more opportunities to export renewable energy “when the wind is blowing and the sun is shining”.

For the party whose Upper House leader once travelled the countryside warning of the potential health effects of wind turbines, this is quite a turnaround, without even stopping to ponder the negative rhetoric about wind power that emerged from party figures after the September 2016 blackout.

The Liberal plan also includes $50 million for a grid scale storage fund, which reveals Marshall’s disparaging remarks about the Elon Musk battery plan as political bluster rather than principled concern.

Marshall has signalled his Government would abandon the state renewable energy target in deference to a national policy, but this is just window dressing. South Australia has smashed every renewable energy target it has set and is likely to continue to do so.

The centerpiece of the plan – at least in PR terms – also has shades of the Rann era.

A Marshall Government will spend $100 million to subsidise the installation of home batteries, potentially leading to a flood of installations, similar to the boom in rooftop solar sparked by the Rann Government’s sweeteners (another policy that had Liberals of the day tut-tutting about escalating costs to the taxpayer).

The Marshall plan does have holes – it will be means-tested but they won’t say at what level. There are questions about exactly who would benefit from an average $2500 subsidy on a $10,000 battery system. Clearly, the poor, and even a fair proportion of the reasonably comfortable, couldn’t afford to pay the difference, at least on current prices.

The Liberals have also added a rather sketchy claim of an average $302 annual saving for SA consumers, about which every voter should exercise suitable caution. That figure has been crumbling as journalists unpick the assumptions. The real saving will be much smaller. As for Labor, it won’t put a figure on the savings to come from its plan.

So it’s a choice for voters between rubbery figures or none at all.

Overall, however, at least the Liberals now have something solid with which to challenge Weatherill’s surprising dominance of the electricity debate for much of this year.

The fact is, as we have pointed out previously, renewable energy is very popular in the community and remained so even after the state-wide blackout. For this reason, the state Liberals have always been more centrist players in the renewables debate than their federal counterparts, who often seem to pay scant regard to the popular views of South Australians. [State energy spokesman Dan van Holst Pellekaan, for example, has been a long-term champion of solar thermal for Port Augusta.]

It’s clear, though, that the energy debate in SA has been reset: it’s no longer about the wisdom of renewable energy, nor the degree of its penetration in the South Australia market, nor pining for the days of coal-fired generation. It’s about which party has the most credible and attractive plan to make our renewables-rich grid more stable and reliable, while maximising economic opportunity.

Even the new third force, Nick Xenophon’s SA Best, is (mostly) on board, with the man himself moderating his previous scepticism about renewable energy and recruiting as a candidate a sustainable energy expert.

The only party still banging the drum against renewables is the Australian Conservatives.

Legislative Council member Robert Brokenshire this week pointed out that the major parties were “Tweedledee and Tweedledum” on the issue.

“The Greens and Nick Xenophon and Labor have all jumped on the renewables bandwagon with little thought to the cost to the community,” he said. “Labor has escalated its renewable push to the point that the state has been left in a bad way, both in terms of the unreliability of the system and the financial cost to the people. Now we see the Libs are going down the same path rather than offering a better alternative.”

So the Liberals will face political static on this issue during the campaign on their right front, as well as from Xenophon – who will say neither party has the solution – and Labor, who are keen to maintain their, frankly, bold-as-brass ascendancy on the electricity issue which, as has been noted before in these pages, should be their primary weakness.

Of course, it’s anyone’s guess whether any of these expensive plans will actually bring down power prices and solve the instability in the South Australian electricity grid. But at least we’re not seeing the entrenched stasis which grips Canberra on energy policy. A small mercy.

David Washington is editor of InDaily.