Net Zero with Mass Migration? Don't Kid Yourself
Why Net Zero Isn’t Zero
Australia’s leaders insist we can do two things at once: have net zero emissions by 2050 and run record-high immigration levels of nearly half a million people a year.
It sounds nice. It isn’t true.
On paper, the slogans sit side by side: green earth, carbon footprint, climate leadership, but scratch the surface and the maths turns ugly. Every extra person who settles in Australia adds to our emissions tally and at current levels of migration, those additions are massive.
The Numbers Our Leaders Don’t Say Out Loud
Every year’s migration surge adds around 8 million tonnes of CO₂ at today’s carbon-heavy settings. That’s the same as putting 3.5 million more emissions-producing cars on our already congested roads.
Even in a so-called “net zero” future, when the grid runs largely on renewables and cars are electric, those same half-million people would still add 2.5 to 4 million tonnes annually. Why? Because there are parts of the economy that simply don’t decarbonise easily. Farming releases methane, cement and steel emit CO₂ in their very chemistry, aviation fuel remains carbon-heavy. These are called residual emissions. They’re smaller than today’s footprint, but they never disappear entirely.
Net Zero Isn’t Zero
This is the critical point politicians gloss over: net zero doesn’t mean no emissions. It means balancing the emissions we still produce with removals — forests, carbon capture, offsets, or other sinks.
Credible modelling for 2050 still leaves around 153 million tonnes of gross emissions each year that must be cancelled out with removals. That’s around 5 tonnes per person to offset. Add half a million more people, and suddenly you need an extra 2.5 million tonnes of removals every year just to stay balanced. Without that, the country slips back into “net positive” territory, and the “net zero” promise unravels.
In other words, every new migrant still comes with a carbon bill. The cleaner the system, the smaller the bill, but it never falls to zero.
The Construction Spike Nobody Talks About
This is all before we even consider the building boom. Housing 500,000 new arrivals requires roughly 200,000 new dwellings. Each one carries a carbon price tag. A recent study found that a typical detached home releases about 185 tonnes of CO₂-e up-front from bricks, cement, steel and other materials. Taken together, if most new builds are detached houses, that’s a one-off spike of up to 37 million tonnes of CO₂-e in the first decade of growth.
Then layer on the rest: the necessary new roads, rail lines, schools, hospitals, shopping centres, and power lines. All of them add to the upfront emissions load. In short, before new arrivals even switch on a light, the carbon budget is already blown out by the materials needed to house and service them.
The Fantasy of Doing Both
Could we technically stay at net zero with mass migration? On a spreadsheet, yes. But in practice, it would mean:
Doubling the already breakneck pace of renewable rollout;
Slashing per-capita emissions faster than any country on earth; and
Somehow conjuring millions of tonnes of new offsets (which are dubious at best) every single year to balance the extra load.
That isn’t a plan. It’s a fantasy. It’s like promising to run a marathon while adding a 20-kilo backpack every kilometre. The maths alone makes the target unachievable.
Australians Asked to Carry the Cost
Meanwhile, ordinary Australians are told to do their bit. Pay higher power bills, buy expensive EVs, retrofit their homes all in the name of climate responsibility.
But at the national level, government policy wipes out those sacrifices by importing more emissions with each new wave of arrivals. It’s like trying to drain a bathtub with one hand while turning the taps on full bore with the other.
The contradiction matters. You cannot demand sacrifice from people while pursuing policies that cancel out those sacrifices at scale, it’s dishonest. Worse, it erodes trust in climate policy altogether.
A Smarter, Balanced Path
No one is arguing for shutting the door completely. Australia will always need skilled workers, students, and a humanitarian intake but scale matters. Half a million a year is not sustainable for housing, for infrastructure, or for the carbon budget.
A sensible migration policy would match intake to what the country can actually provide: homes, services, jobs and crucially, a carbon budget that isn’t already overspent. That means a lower, steadier intake, coupled with a genuine plan to decarbonise in a responsible way.
Until then, politicians need to stop selling the lie that Australia can have it both ways. We can have net zero. We can have mass migration (that is another discussion to be had) but we cannot have both — not at the same time and not at the scale our leaders pretend is possible. To try would be irresponsible and destructive.