Imagine a world without coal, one where mining companies didn't dig up fossil fuels but instead kept them in the ground where they couldn't be burned.
It's a challenging concept, but one Australia's climate change experts say we must come to terms with — fast — if we're to have any chance of avoiding the most dangerous consequences of an overheated atmosphere.
In its latest report, the Climate Commission says there needs to be a fundamental change in the way we create energy if international targets for global warming are to be met.
The best chance we have of doing this, the commission argues, is to invest heavily in renewable energy, phase out coal and keep most of the world's known fossil fuel reserves in the ground.
One of the authors of The Critical Decade, Professor Will Steffen, knows it's a confronting idea, but says the risks of maintaining a business-as-usual approach are just too high.
"The scientific understanding that underpins this is pretty persuasive," he said.
"If we choose to take the risk we may be condemning our children and grandchildren to a world they can't live in."
Most nations, including Australia, have agreed the risks of allowing global average temperatures to rise above two degrees are too great for the environment and the world economy.
Prof Steffen says scientific consensus is that no more than 600 billion tonnes of CO2 can be burned by 2050 if we're to have a decent chance of meeting that target.
Problematically, if all the world's known fossil fuel reserves are dug up and burned, this "carbon budget" would be blown out by around five times.
"Burning all fossil fuel reserves would lead to unprecedented changes in climate so severe that they will challenge the existence of our society as we know it today," the report says.
The call to keep that "unburnable carbon" in the ground is gaining attention but will face stiff opposition in Australia where an unprecedented mining boom is well underway.
Prominent US activist Bill McKibben rattled the cage during a recent tour of Australia, where he called on concerned citizens and businesses to stop investing in fossil fuel companies.
The Climate Commission, while not going this far, has warned Australia's coal reserves alone would exhaust a large portion of the global carbon budget.
Prof Steffen believes it's time to start thinking beyond fossil fuels to "the next revolution" in power generation, and ways to drive down emissions by the end of this decade.
"We humans are creative and we can change really fast," he said.
"I think we should look more positively at the possibilities of unleashing our creative talents to actually solve this problem."