New data is fuelling concerns WA's energy grid is not embracing renewables quickly enough to transition away from coal by the end of the decade.
The state government has committed to closing WA's last coal-fired power plant by 2029 to help accelerate the road to net zero.
But data released by the Clean Energy Regulator showed of all the renewable energy capacity deemed either 'committed' or 'probable' last year, only 5 per cent was in WA.
That is about half of what the state would get on a per-capita basis.
"It's a really big concern that WA's not getting its fair share of renewable energy in the pipeline because if we're going to do this transition, we're actually going to need the renewable energy to replace the coal," Greens MP Brad Pettitt said.
"The worst thing that could happen is that we see that coal come out of the system and largely be replaced by gas because we haven't moved quickly and early to replace that with renewable energy, and especially wind.
"We actually need to absolutely ramp that up and to make sure that we are doing proper investment now, otherwise that clean energy transition simply can't happen."
Renewable energy consultant Liz Aitken says part of the problem for some projects is that almost everything is ready for them to be built, but they cannot get a connection into the grid.
She said upgrading the grid to accommodate all the renewable projects the state needed could cost tens of billions of dollars.
"It is a really big task and we need to start working on it straight away," she said.
"We need to be building, we need to see what the plans are, we need to get in queues for supply, for people, for capabilities, and we also need to think about how we're actually going to fund this.
"The concern here is that, will the government be required to step in and actually take over some of the coal assets in order to keep coal-fired generation running for longer, because we're unable to actually connect wind farms?"
It follows warnings from renewable energy developers and operators that decarbonisation efforts risk being derailed because of competition for workers and resources from the United States.
"How they're actually going to find the people, the capabilities, the skills to actually build this infrastructure in such a short time should be the primary focus of everything that [Energy Minister] Bill Johnston and [Premier] Mark McGowan are doing at the moment," Ms Aitken said.
A state government spokesperson said it was "engaged with industry to progress an assessment of the future demand for renewable energy on the South West Interconnected System, which is expected to inform future transmission network investment planning".
That includes an interim assessment, before the state's next "Whole of System Plan", which is required by 2025.
Gas could be fallback plan
If renewables cannot be built and connected to the grid in time, the state government will effectively be left with two options: increase reliance on gas or drag out the life span of coal.
The government has not ruled out adding new gas-fired capacity before 2030, with Alinta indicating it would be keen to build an extra gas-fired plant if one was needed.
In December the Australian Energy Market Operator said it expected gas demand to more than double between 2023 and 2034 "as coal power station retirements are only partially replaced by renewables".
It is a path favoured by UWA Centre for Energy director Dongke Zhang, who is concerned WA has already introduced too much renewable energy into its grid.
"Natural gas is uniquely important for WA for two reasons," he said.
"Number one, natural gas is the least carbon-intensive fossil fuel, so by all means natural gas is the most reliable and logical, scientifically, logical path towards [a] low-carbon future as we move away from coal.
"Second, natural gas is a rich resource in WA, relative to other jurisdictions, and we are one of the largest LNG producers and exporters and we have huge quantities of natural gas that can serve our economy."
But that option would not be without its critics.
Professors from WA's five universities last year accused the WA government of being "too close to the LNG industry" as they called for tougher action on climate change.
Environmental scientist Peter Newman, who was part of the group, said they were not trying to stop projects, but modify them so they aligned with emissions reduction targets.
"Anything new in oil, gas and coal basically shouldn't happen unless they are able to completely modify their greenhouse gas implications," he said at the time.
"We have to take climate seriously."
Woodside was this week accused of not taking its emissions responsibilities seriously, after reducing its carbon output last year by just 1 per cent more than the year before and continuing to build new gas projects, including in WA.
Ms Aitken also doubted a new gas project would be viable.
"Are you really going to build a gas-fired power station that's only going to work for 10 years when it's a 25-year asset?" she asked.
"I don't think you'll find very many people who would be prepared to undertake that."
'The deadline was yesterday'
Dr Pettitt called for urgent action to address the missing renewables.
"The deadline was yesterday because there is a global race for this," he said.
"If we don't invest in renewables now, we're going to be throwing good money after bad through actually propping up ageing coal-fired power stations that need to be closed down, just keeping them going, which will cost taxpayers dearly."
The upper house Greens member, whose doctorate was in sustainable development, said that was already happening with the state government making $19.5 million available to struggling coal miner Griffin to keep their operations running.
He rejected the idea of investing further in gas, which he said was "entirely inconsistent with WA's state trajectory to net zero."
A state government spokesperson pointed out the Clean Energy Regulator's data was based on public announcements only and said "its information may not be complete and may change retrospectively".
"The McGowan government is managing the orderly transition away from coal-fired generation," they said.
"As part of our plan, we've allocated around $3.8 billion to invest in green energy infrastructure, including the development of 810 MW of wind generation and 1,100 MW of energy storage over the next seven years."
Gas key to government's transition
The spokesperson acknowledged AEMO's expectations about the role of gas, adding: "The reliable supply of lower-cost gas facilitated by the state's Domestic Gas Policy will be critical to managing Western Australia's energy transition.
"The need for any new gas generators will be determined by a combination of factors, including future energy demand in the wholesale energy market, volume of renewable generation in the market, system requirements and network requirements.
"The state government continues to monitor energy demand requirements and will seek to secure additional gas generation capacity if needed."
Dr Pettitt said he would believe the government's progress when it came to fruition.
"You can talk up your plans all you like but if you're not getting these projects on the ground and built and even planned for, then we've got a major problem," he said.
