There are enough resources on this planet to support a population three times larger than today, and still provide a decent standard of living to all, new research has found.
Far from returning us to the 'stone age', sweeping environmental and economic reforms could take our global energy consumption back to what it once was in the 1960s, when the world was home to only 3 billion people.
If we go about this in the right way, researchers think by 2050, we could support a population nearly three times bigger, with each and every one of us receiving shelter, food, proper hygiene, high quality healthcare, education, modern technology, and limited access to private vehicles and air travel.
At the same time, we could also cut our global energy consumption by 60 percent.
That's only a quarter of what we're currently forecasted to consume by 2050, and under this utopian scenario, everyone's receiving the same slice of pie.
"While government officials are levelling charges that environmental activists 'threaten our way of life' it is worth re-examining what that way of life should entail," says ecological economist Julia Steinberger from the Université de Lausanne in Switzerland.
"There has been a tendency to simplify the idea of a good life into the notion that more is better. It is clearly within our grasp to provide a decent life for everyone while still protecting our climate and ecosystems."
What the 'good life' means is obviously subjective, but the authors say if we focus our efforts on low-energy housing, widespread public transport, and diets low in animal-based foods, we could be well on our way to achieving 'goodness' for the greatest number.
While some studies suggest Earth is not equipped to deal with the lives of over 7 billion people, such projections are often based on continued global economic growth, high-consumption modern lifestyles, and a fixed carrying capacity for the planet.
In reality, making equal room for all the new people expected on our planet will require massive, large-scale changes to global consumption habits, widespread deployment of modern technology, and the elimination of mass global inequality, researchers say.
But the daily comforts of modern life might not have to change all that much. In fact, the new study is a rebuttal against the "clichéd populist objection" that environmentalists want us all to return to cave times.
"Yes, perhaps," the authors write, tongue-in-cheek, "but these caves have highly-efficient facilities for cooking, storing food and washing clothes; low-energy lighting throughout; 50 litres of clean water supplied per day per person, with 15 litres heated to a comfortable bathing temperature; they maintain an air temperature of around 20 °C throughout the year, irrespective of geography; have a computer with access to global ICT networks; are linked to extensive transport networks providing ~5000-15,000 km of mobility per person each year via various modes; and are also served by substantially larger caves where universal healthcare is available and others that provide education for everyone between 5 and 19 years old.'"
Sounds idyllic for a cave, and it's also pretty great for our planet.
Today, only 17 percent of global energy consumption comes from renewable sources, but the authors say that's nearly half of what we would need by 2050 for their 'good life' scenario to be realised.
To figure this out, researchers built an energy model based on materials deemed necessary for humans - from a regular food and water supply, to thermal comfort and mobility. The way climate change will impact these factors in the coming years was also taken into account.
The model is not exactly realistic or practical, but it does show how we could rearrange our planet to make room for a burgeoning population.
For one, the model requires the world's entire housing stock to be completely replaced with advanced new buildings, which require very little heating or cooling. This goes for other buildings, too, including those for education, healthcare and industry.
The chances of such a global housing overhaul actually happening are beyond slim, and the authors admit the removal of all these buildings could be more energy-draining on a practical level.
Still, when the team's model already assumed these advanced 'retrofits' had been built, its ultimate energy predictions barely changed.
"Overall, our study is consistent with the long-standing arguments that the technological solutions already exist to support reducing energy consumption to a sustainable level," says earth and environment scientist Joel Millward-Hopkins from Leeds University.
"What we add is that the material sacrifices needed for these reductions are far smaller than many popular narratives imply."
The current study is based on a huge global, big-picture model, so it comes with many limitations. The broad overview is only focused on the world's final energy consumption by 2050 and does not advise nations on how to actually get there, which is really the hardest part.
Instead, it shows us what can be achieved if we set our minds to it. It draws the finishing line, and now it's up to us to cross it.
"The current work has little to say here in the way of specifics," the authors admit, "but there are some things that can be said with more certainty."
Green consumerism, for instance, which is notoriously middle class and white, was found to be a privileged and inadequate response to the climate crisis.
The "indefinite pursuit" of economic growth, along with unemployment and vast inequalities are in direct opposition to environmentalism, the authors say, no matter how much wealthy people try to limit their individual footprints.
Right now, the world burns through most of its energy for the year long before it actually ends, and much of that is being driven by the wealthy.
Sacrifices clearly need to be made for the greater good, not only to level the playing field for all humans, but to reduce our dependence on fossil fuels and materialism in general.
"Eradicating poverty is not an impediment to climate stabilisation, rather it's the pursuit of unmitigated affluence across the world," argues Narasimha Rao from Yale University.
The study was published in Global Environmental Change.