What is fusion?

All stars, including our Sun, are made of plasma. Stars generate enormous amounts of power through a process called fusion. Harnessing this power here on Earth would give us a near limitless supply of low-carbon energy.

Here, we will find out about the process of fusion, why we are working towards it, and what this ‘star in a jar’ might look like.

Why fusion?

The process of fusion creates no carbon dioxide. This means that the reaction does not contribute to climate change.

The fuel needed for fusion (hydrogen) is also readily available or easily made here on Earth. This means that fusion has the potential to provide a near limitless supply of energy.  One of the so-called isotopes of hydrogen is called deuterium and makes up about one in every 6,000 atoms of hydrogen found in seawater. The second is another form of hydrogen, known as tritium. This is radioactive, so not found abundantly in nature. However, we can make it in the fusion power plant by breaking down lithium nuclei. A single bath of seawater and the lithium from two laptop batteries provides enough deuterium and tritium to provide the average lifetime power needs for one person living here in the UK.

As it is a nuclear process, fusion does create some radioactive waste. However, this waste decays very rapidly and does not remain radioactive, so there is no need to find long-term storage solutions. There is also no ‘chain reaction’ in fusion – in fact, the difficulty is keeping it going, not making it stop! This means there is no risk of a meltdown and this is a technology that can be safely shared with the world.

What do you already know about fusion? Had you heard of it before?