The Andrews Labor government believed it was on to an election winner with its Solar Homes policy, which featured a headline-grabbing target to put subsidised panels on 650,000 properties in 10 years.

Premier Daniel Andrews unveiled the $1.3 billion scheme in suburban Melbourne, declaring it would save households up to $890 each year on their bills.

Amid federal coalition infighting over Malcolm Turnbull's doomed national energy guarantee, Victorian Labor spent the next three months spruiking the signature promise before its thumping victory that November.

The program has since expanded its eligibility and increased its goal, aiming to hand out rebates for solar panels, solar hot water systems or batteries across 770,000 homes.

It is on track to hit the target despite applications slowing last financial year, with almost 220,000 rebates given as of mid-October.

Labor again raised the stakes on Victoria's energy transition this election, promising to bring back the State Electricity Commission to oversee $1b for state-owned renewable projects.

It will also increase the 2030 emissions reduction target from 50 per cent to 65 per cent and has set a 95 per cent goal by 2035.

Dogged by the issue four years ago, the Victorian coalition has shifted on climate change, supporting the state's 2050 net zero emissions target and promising to legislate an interim goal of 50 per cent below 2005 levels by 2030.

Leaders across the political divide are finally grappling with the need to transition from coal-fired power, particularly after AGL's decision to close its Latrobe Valley plant 10 years early, according to Victoria Energy Policy Centre Director Bruce Mountain.

"There's a shifting landscape," he says.

"There are no votes to be won in saying you're not going to adjust to climate change or the clean energy sector."

Melbourne Energy Institute's Pierluigi Mancarella believes Russia's invasion of Ukraine reinforces the need to shore up energy security.

"Regardless of what politicians think about climate change, it's an issue of supply," the professor of electrical power systems at the University of Melbourne says.

"Renewables guarantee the security of supply. It's a win-win solution."

The solar homes program hasn't been without hiccups.

Its overwhelming popularity forced a temporary freeze on rebates and subsequent monthly cap not long after its launch in 2019, before a dodgy installer was busted for using unlicensed electricians.

An Auditor-General review published last year found the program's success couldn't be measured, as government agency, Solar Victoria, didn't finalise its evaluation methods until April 2021.

A full business case was not prepared before the program launched and August 2020 safety audits found about a third of installations were sub-standard and two per cent were unsafe.

Energy and Solar Homes Minister Lily D'Ambrosio still bristles at the auditor's assessment, rejecting the view the scheme was set up too hastily.

"The proof is in the pudding," she said last month.

"Victorians have run to the Solar Homes program and right now they are enjoying savings of about $1000 a year off their power bills."

When first mooted, opposition energy spokesman David Southwick thought the program reminiscent of the Rudd government's ill-fated pink batts scheme linked to the deaths of four workers.

The deputy Victorian Liberal leader says it's fortunate no one was killed under Solar Homes, given the planning deficiencies exposed.

"We were very lucky we caught it when we did," Mr Southwick says.

"If it would have continued to be rolled out in a way of having dodgy operators putting panels on people's roofs, then there was every possibility."

Despite Solar Homes' ties to Labor, Mr Southwick says the program won't be dumped if the coalition is elected on November 26 and will be broadened to let households claim both panels and batteries.

With the need for an orderly transition to renewables settled among the major parties, Prof Mountain says policymakers must move faster to decentralise the energy network and Solar Homes can play a bigger role.

"We need to get (panels) on just about every industrial roof we can. It's the cheapest source of production and ... it's so much easier to do than building out networks," he says.

The next step, Prof Mancarella adds, should also include greater investment in network integration to prevent congestion issues as more houses install solar, including through community batteries.

Labor wants to do exactly that after this week promising to spend $42m to install 100 across the state if it secures a third successive term in government.

Australian Associated Press