The $1.3 billion solar program, which aims to subsidise 770,000 Victorian homes to install solar power within 10 years, was a major promise by the Andrews government before last year's state election, but has been stifled by cost blowouts, unexpected demand and shonky solar operators.

The new monthly cap comes after 600 homeowners were left high and dry last year after they paid to install solar equipment but were unable to claim the rebate when the government suddenly halted the program in April due to huge demand.

The government originally expected to provide 24,000 rebates between September last year, when the scheme started, and April.

But it accepted 32,000 applications in that period.

And six solar providers, which exploited vulnerable customers and exposed workers to unsafe conditions, were referred to Consumer Affairs Victoria for prosecution.

The rollout from July 1 will cover close to 40,000 rooftop solar systems over the next year.

In addition to that 2000 rebates will be available for solar panels on rental properties over the year, 6000 for solar hot water systems and 1000 for solar battery systems.

The monthly supply of 3333 rebates is expected to be snapped up within days – possibly hours – of the first day of the coming months.

Premier Daniel Andrews said the anticipated over-demand was "a good problem to have".

"We fully expect there will be more people who want these panels than we can safely, responsibly, appropriately install in any given month," he said on Tuesday.

"But what will happen is industry will rise to that challenge, as we train more people, as more firms become part of this vibrant sector, then our capacity, how much we can do every month, will grow."

Under the changes to the scheme, customers will be required to go through a retailer and get a tick of approval on the rebate before solar panels are installed.

Mr Andrews said his government made "no apology for putting safety first" in the more measured approach.

"I'd prefer to be perhaps criticised for the fact we've done this in a careful, methodical way rather than rushing it out and potentially having problems," he said.

Mr Andrews also promised a more rigorous auditing program of providers and installers from next month. "We will check and double check to make sure this is done properly," he said.

However, the rebate amount and conditions have remained the same – up to $2225 is available to households with a combined income of below $180,000.

Mick Harris, the managing director of Melbourne-based solar company EnviroGroup, praised the new scheme because "the floodgates aren't being completely opened" and backed it to "remove the shonky operators".

"We in the industry have been crying out for good quality control for a long, long time, and this is delivering that, so we're very happy with that," he said.

Minister for Solar Homes Lily D'Ambrosio said the government was expecting high demand from both landlords and tenants as the scheme opens to renters for the first time.

"It's an area that hasn't been tackled before by governments in this country … we know and are aware there are a number of landlords out there that want to do the right thing," she said.

"That's either because it is the right thing to do in terms of producing low emissions energy, or because it's a really good investment opportunity and is a selling point for many tenants."