Thousands of solar power users in Western Australia are reeling from the State Government's announcement that it will slash feed-in tariffs.
Some say they won't be able to pay back the loans they took out to install solar photovoltaic (pv) panels on their homes.
In 2010, the government said it would return 40 cents per kilowatt hour of energy to homes generating solar power that they fed back into the electricity grid for the next 10 years.
In May 2011, they cut that amount to 30 cents for new people signing up to the scheme and then stopped the feed-in tariff altogether last year as the price of solar panels dropped dramatically.
By then, 75,000 West Australians had signed onto the scheme.
Under the changes announced in Thursday's state budget, those who signed up initially will see their payments drop from 40 cents to 30 cents in October and then to 20 cents next year.
"Our view is that the feed-in tariff is another example of a government program which is non-affordable in the current environment," Mr Buswell told a press conference.
The Synergy notice sent to solar customers in May 2011 reads: "As an existing residential net feed-in tariff customer, Synergy is pleased to advise that your subsidy rate of 40c/kWh will not change and you will continue to receive 40c/kWh for the net export of electricity for the full term of your 10 year contract."
A contract the Treasurer said he was allowed to break.
"The advice we've had is that what we're doing is allowable within the constraints of the contracts," Mr Buswell said.
Dr Geoff Evans is the national campaigns manager for the community organisation Solar Citizens.
He said he was immediately inundated with calls from people expressing their concerns and outrage at what he called the 'betrayal' by the WA government.
"They feel outraged because they spent their precious family fund to invest in solar in mid 2010 through to 2011, thinking they would have a guaranteed price for the power that they produced, that would enable them to work out how long it would take their solar power system to pay for itself," Dr Evans said.
"Now the government's pulled the rug from under their feet and changed the rules and it's caused them to reconfigure their budgets and makes the pay back time and whole investment much longer."
Dr Evans said it would hit those people who had signed up to the program early particularly hard.
Back in 2010, solar pv panels cost upward of $12,000.
He said the people who invested in the technology were low to middle income families on the outskirts of the metropolitan area.
"These are not the wealthy inner city people," he said. "These are people whose budgets are tight, they made a carefully calculated decision, now they feel like they've been done in by the government."
Callers into ABC Local Radio the morning after the budget was handed down were angry about the tariff changes.
Steph invested $20,000 in solar in 2010 and has a contract saying she would be paid at the 40 cent rate for 10 years.
"It's a broken promise," she said.
"He (Buswell) got it wrong and now the rest of us have to pay for it. If you did this in business, you'd be in court."
Graham said; "How can they do this? If I've accepted a contract for 10 years should I contact Consumer Affairs to go over the contract?".
Rob from Wanneroo said he was appalled at the change to the feed-in tariff because he too had what he thought was a binding contract.
Lyn said; "It seems that this government not only can't keep its promises but also the contracts it undertakes are as worthless as their word".
John asked; "Does this mean a government can go back on a contract?"
And Peter said he took out a loan to afford the panels in 2010; "When I did my sums to see if I could afford my solar panels I took the 40c for 10 years to be guaranteed by the State Government and I though if you can't trust the State Government with a contract, then who can you trust, I don't have enough money now to pay my repayments on the loan I took out to buy them".
Dr Evans said concerned solar users have discussed launching a class action against the Government.
"People are talking about taking legal action against the government for breach of contract, people are talking about marching in the street to express their outrage," Dr Evans said.
"For the Minister to just say 'Well I'm just going to tear up the contracts' is a slap in the face for tens of thousands if not millions of solar owners around Australia."
He is also concerned about the precedent it could set across the country, where it has the potential to affect millions of Australians who have invested in solar panels.
With 2.5 million Australians living under solar roofs around the country, that's a big voting block.
"It could end up being a backlash against the Government because a lot of solar owners live in marginal seats in WA," he said.
"WA is the first state in Australia that has rewritten the rules for people who are in a solar contract."
Hundreds of West Australians have already signed a petition against the changes on the Solar Citizens website.
"Solar owners need to be able to trust that the big organisations and government will protect them, not rip up the contracts half way through their period," Dr Evans said.
He said people are already looking for alternatives to being dependant on those big power companies.
"The technology around renewable energy is changing very quickly so if these big power companies are going to rip people off, people are going to start using the emerging technologies around solar to actually get off the network.
"Theoretically millions of Australians could have solar panels on their roof, store their power in batteries and have nothing to do with the network and if that happens because people don't trust big power companies, the whole business model of the whole power industry could just collapse."
The Sustainable Energy Association (SEA) says it is no time for the Government to move away from solar incentives.
The Association's CEO Kirsten Rose says the changes are a massive betrayal of public trust.
"When the feed-in tariff was implemented in 2010, it was designed to encourage the uptake of solar PV, when it was significantly more expensive that it is today," she said.
"Now after two-and-a half, three years, the Government has decided to wind that back and that's going to leave some people in a financial hole.
"It is a broken promise from the government so it will have a trust impact."
In 2012, 75,000 WA homes had solar panels.
That figure is now up to 131,000 homes.
In other states, users still get paid tariffs as high as 66 cents per kilowatt hour.
The SEA said the solar pv industry no longer needs feed-in tariffs and those considering installing a system in their homes, they shouldn't let the sun set on that idea.
The cost of a solar panel system has reduced dramatically over the past few years, down to as low as $1,800 according to the SEA.
"This doesn't effect anything going forward," Ms Rose said.
"Solar is a great option for people to put on their houses to help insulate them from future price rises in electricity and it's more economic than ever without any subsidies and any government support at all."
But Dr Evans said that doesn't help the 75,000 West Australians who signed up at the beginning.
"The feed-in tariff is not so critical for people now, but for those people who invested then, it was a really critical part of their decision and they still depend on that money to make ends meet," Dr Evans said.