In 2016, Tasmania was on the brink of a months-long statewide blackout when its undersea electricity cable broke and its dams were nearly empty.
But these days, it can produce more than enough power locally to supply homes and businesses.
So, should the island unplug from the rest of Australia?
Tasmania only hooked up with the National Electricity Market in 2006 when the Basslink undersea power cable to Victoria started operating.
Before that, the island state relied on its network of hydro-electric dams and generators to provide enough power for homes and businesses.
It's been a rocky relationship since then.
Tasmanians have enjoyed low electricity prices when power on the Victorian market was cheap, and faced higher prices when the Victorian market was expensive, like now.
In 2016, Basslink itself broke, leaving Tasmania alone with dwindling hydro-dam water levels that threatened the state's ability to keep the lights on.
Now there's been more rain, we've got a few big wind farms and we can produce more than enough power locally.
So should Tasmania take the plunge and separate, or "delink", from the National Electricity Market?
Wait, what is the National Electricity Market anyway?
The National Electricity Market is usually referred to as the "NEM" and it includes Queensland, New South Wales, the ACT, South Australia, Victoria and Tasmania.
The NEM is a wholesale electricity market run by the Australian Energy Market Operator (AEMO).
All of the power stations in the eastern states have to offer the electricity they can generate for sale on the NEM, and all energy retailers have to buy the energy they supply to homes and businesses from it.
Every five minutes, AEMO picks the generator that is offering power for the lowest price and tells them to start sending power into the grid.
This is called the "spot price".
Marc White from Goanna Energy Consulting said this keeps power prices for consumers as low as possible.
"The purpose of the national electricity market is to ensure that the cheapest electricity is dispatched every five minutes of the day to meet customers' needs and therefore customers benefit from the lowest possible cost of electricity at all times of the day."
How is Tasmania linked to the NEM?
Tasmania's link to the NEM is both financial and physical.
The prices Tasmanian homes and small businesses pay for electricity are related to the price of electricity on the Victorian market, so as power prices rise and fall on that market, they rise and fall in our power bills.
If you want to know more about that relationship, check out this story.
Tasmania is also physically linked to the market by the Basslink cable.
Hardly anyone is calling for that physical cable to be cut — it's important for Tasmania's energy security, as the 2016 outage showed — so any delinking from the NEM would be financial, not physical.
Didn't the Liberals promise in 2018 to delink from the NEM?
Yes, they did.
Before the 2018 state election, which the Liberals won, the party promised to break ties with the NEM and stop linking Tasmanian electricity prices with the Victorian market by 2021.
They said it would cut Tasmanian retail power prices by up to 10 per cent.
In 2017, the Tasmanian parliament passed a law that allowed then-energy minister Matthew Groom to set the wholesale price that Hydro Tasmania charged for its power.
This kept a lid on retail power prices paid by households and small businesses, which are strongly influenced by the wholesale price.
For more information about the wholesale price, read this story.
But doesn't Labor say the Liberals broke their delinking promise?
The wholesale price cap remained in place until 2020, when Victorian power prices were lower, so it was removed.
Tasmania's Labor Opposition argues the Liberal Party broke their election promise because it didn't permanently delink from the NEM, leaving Tasmanians to face higher prices now.
"The Tasmanian Liberal government has broken its promise to de-link from the National Electricity Market," said Labor energy spokesman Dean Winter.
Energy Minister Guy Barnett counters that the wholesale price cap in 2017 means the Liberals did "effectively" delink from the NEM.
Marc White agrees the cap was a legitimate form of delinking from the NEM, because it broke the financial relationship with Victorian prices, even if only for a period of time and not permanently.
Should Tasmania delink from the NEM again?
Mr White thinks the Tasmanian government should consider it.
He said the best way to do this would be for the state government to again temporarily impose a cap on the wholesale price that Hydro Tasmania charges for its power.
"They could reinstitute another wholesale cap and regulate the power price locally, and that may have some benefit as it did back in 2017-18", he said.
But Mr White said the cap should be removed when power prices in Victoria fall below those being charged in Tasmania.
He said the state government was too slow in removing the wholesale cap it imposed in 2017, which meant Tasmanians ended up paying higher-than-necessary prices for several years.
Would delinking from the NEM cause any problems?
The biggest loser from delinking would be Hydro Tasmania.
The Government Business Enterprise is not paying more to generate electricity, but the prices it gets for its power on the NEM have skyrocketed.
Mr White says delinking would mean Hydro's profits would go down.
Delinking would also hurt other renewable energy projects which will be more profitably if they're able to generate electricity cheaply in Tasmania and then sell it for higher prices on the NEM.
These include wind farms and Hydro Tasmania's proposed Battery of the Nation pumped hydro projects.
Mr Barnett said the government needed to avoid unintended consequences.
"Exiting the National Energy Market would erode investor confidence in the Tasmanian energy market and potentially jeopardise billions of dollars in current and planned future investment in renewable energy projects, including in Marinus Link, new wind energy and Tasmanian green hydrogen projects," he said in a press release this week.
The Liberals were warned about these potential risks in 2018 when it made delinking from the NEM an election promise.
Are there any alternatives to delinking that would also cut power prices?
The Tasmanian government has budgeted for $305 million worth of power bill concessions for eligible Tasmanians on low incomes.
More and higher concessions could be offered and the Tasmanian government has said it is considering that.
