Scammers have tried to cash in on the Victorian government's $1.3 billion solar power subsidy scheme.
Solar Victoria, which will oversee the program, said it's concerned about some contractors who are promising to help install rooftop panels, hot water systems and battery storage units following the government's election announcement.
"We have received alerts that scammers have been targeting Victorian households," Solar Victoria warns on its website.
"Be alert to callers claiming to be from the Victorian government or Solar Victoria requesting bank account details.
"We will never ask you to provide personal details such as banking information over the phone."
Last month the government announced its $1.34 billion Solar Homes program which also includes half-price solar panels for 650,000 households and $1000 off the cost of solar hot water systems with rebates for 60,000 homes.
Most of the cash is contingent on Labor's re-election at the November 24 state election, but rebates are already available for some households.
Premier Daniel Andrews said he was confident public watchdogs could keep an eye on the program.
"If you're being contacted by somebody, then that is not from the Victorian government, but I'm confident Consumer Affairs can handle this," he told reporters on Tuesday.
Opposition energy spokesman David Southwick in parliament highlighted the case of a 72-year-old pensioner in regional Victoria who was door knocked by a solar retailer.
"Despite telling the sales rep he was not interested in purchasing solar panels, the salesman let himself into John's home and refused to leave until he signed up to a $9000 solar panel system on a financing plan he could not afford," Mr Southwick said.
"What guarantees can you give that thousands of Victorians won't end up with dodgy sales people knocking on the doors, phoning them, all hours trying to sign them up to solar panel deals that will leave them thousands of dollars worse off?"
Energy Minister Lily D'Ambrosio re-affirmed the program would not be cold-calling anyone and if people are approached, they should contact Consumer Affairs and Solar Victoria.
More than 12,000 people have registered their interest in the program already, she said.
