ITER – the world’s largest nuclear fusion project – reached a construction milestone last week as the final components of the reactor arrived on the build site in southeastern France. The $25 billion endeavor, which aims to produce sustainable fusion energy on a commercial scale, is financed by seven of the world’s largest energy powerhouses: the European Union, United Kingdom China, India, Russia, Japan, South Korea and the United States.
The origins of the ambitious project go back to the Reagan-Gorbachev negotiations of the 1980s that envisioned equal participation by the Soviet Union, the United States, Japan and Europe. After decades of delays, the International Thermal Experimental Reactor was born. ITER began in earnest in 2010 and is now celebrating the commencement of the “assembly phase” wherein the reactor’s components can now start being put into place.
With millions of components manufactured from around the world, weighing in at 23,000 tons, and standing several stories high, ITER may be the most complicated engineering project in human history. The reactor will contain some 3,000 tons of superconducting magnets which will be linked by 160 miles of superconducting cables, all kept at -269C by the largest cryogenic plant in the world.
The fusion process is the same one that powers our sun: you can think of a star as one gigantic fusion reactor. Hydrogen atoms forced together under immense heat and pressure break their atomic bonds, fusing into a new heavier element, helium. Some mass is lost in the process, and great amounts of energy are released as a result. This is what Einstein’s famous formula E=mc² describes: the tiny bit of lost mass (m), multiplied by the square of the speed of light (c²), results in a very large figure (E), which is the amount of energy created by a fusion reaction.
The catch is that these reactions generate very hot and very unstable globs of plasma (in excess of 100 million Kelvin/ 500 million degrees Fahrenheit) which require tremendous amounts of energy to maintain. To date, the longest recorded sustained plasma operation is just over one minute long. Enormous magnets are required to keep the plasma in a doughnut-shaped vacuum chamber, which is called a “tokamak.” ITER is far and away the largest tokamak reactor in existence.
Like conventional nuclear (fission) reactions, the fusion process does not emit carbon dioxide, but unlike a nuclear plant, a fusion reactor cannot melt down. Fusion plants can be fueled by the hydrogen found in just a few ounces of seawater and don’t rely on radioactive materials. As a result the process produces virtually no waste, making it a climate friendly, safe, and reliable source of near unlimited power – if we can get one to work.
ITER is supposed to become the world’s first reactor capable of self-burning plasma and would ideally generate up to 10 times the amount of heat that it consumes. The components of the reactor include a 100ft-diameter cryostat, a device manufactured by India that is intended to surround the reactor and keep its vital components from overheating. US-manufactured central solenoid magnets responsible for inducing and stabilizing the superheated plasma make the backbone of the reactor. When at full power, these ‘super magnets’ they will have the capacity to lift an aircraft carrier.
Large-scale international cooperation on such a complex project is an example how scientific research knows no geographic borders. This model was and should be adopted in other areas of science, such as space exploration. Yet, the ITER project appears to be both bulky and expensive, and has inspired many smaller enterprises to develop their versions of fusion generation technology.
These include UK-based Tokamak Energy, which has already raised over $130 million in investment. Similarly, California-based Tri Alpha Energy, which is backed by Microsoft
The start of the assembly stage of this colossal international project, though remarkable, does not mean that the project is yet near the finish line. ITER plans for all the core parts of the reactor to be installed, fully integrated, and ready to produce its first plasma by November 2025 (the 40 year anniversary of of Ronald Reagan and Mikhail Gorbachev’s historic U.S.-Soviet Geneva summit). If successful, the reactor will draw 50 megawatts (MW) of electricity to ignite the fusion process and produce stable plasma. This plasma would then put out some 500MW of power (in short bursts), thereby generating a whopping 10x energy return.
Despite numerous delays over the years, ITER is aiming to achieve full plasma generation by 2030. While this may be consistent with a common adage in the power industry: “Fusion power is always just 10 years away,” progress in harnessing fusion is unquestionable, and, if commercial fusion is achieved, the current generation is likely to see a total revolution in energy in their lifetimes.
With Assistance from Bogdan Puchkov