By The Numbers: Progress On The World’s Largest Science Project

The International Thermonuclear Experimental Reactor (ITER) is building the world's biggest fusion nuclear reactors.

Aerial view of the project site from 2016 (Image credit: EJF Riche via ITER)
Aerial view of the project site from 2016 (Image credit: EJF Riche via ITER)

In the south of France, the International Thermonuclear Experimental Reactor (ITER) brought together an impressive international coalition including China, the EU, the U.S., Russia, India, Japan and South Korea in 2006. The goal? Build the world’s biggest fusion nuclear reactors and solve the technological challenges of harnessing fusion for commercial use.

Unlike traditional fission power — which splits heavy nuclei into lighter, unstable nuclei — fusion combines two hydrogen isotopes, tritium and deuterium, to create lots of energy.

On paper it sounds perfect. Tritium and deuterium are in abundant supply, the process would generate almost no nuclear waste, there’s no risk of meltdown and it could produce enough power to solve the world’s energy needs potentially forever.

In reality, the ITER project has been plagued with delays and budget problems since the get go.

Earlier this year the project’s management announced that it was going to take even longer and cost more to get the reactor going. But world leaders are still in support of what would be one of the most important revolutions in energy production. 

Aerial view of the project site from 2016 (Image credit: EJF Riche via ITER)Aerial view of the project site from 2016 (Image credit: EJF Riche via ITER)

Here’s a look at how it’s unfolding, by the numbers.

60 = Years that scientists have been attempting — but failing — to produce a fusion reaction that creates more energy than it consumes.

About $20 billion = The estimated amount that will be invested in ITER by 2025. The original estimate was about $5 billion.

500 = Megawatts of energy ITER is hoping to produce from 50 megawatts of input.

5,000 = Workers at the ITER site during its peak construction.

60 soccer fields = The relative size of the ITER site.

23,000 tons = The weight of the ITER reactor, once it’s built (that’s more than 100 Statue of Liberties).

150 million degrees Celsius = The temperature ITER is designed to heat up hydrogen gas to in its donut-shaped Tokamak container.

2025 = When the ITER reactor is now slated to be fired up for the first time.

4.5 billion = The number of years fusion energy has kept the sun blazing. It’s estimated that it will burn for another 4 billion more. 

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