Is nuclear energy renewable?

By many definitions, nuclear energy is not renewable. But in terms of climate change, nuclear energy production does not release greenhouse gases, so it is a low-carbon fuel.

Renewable energy refers to energy from sources that are constantly replenished - like the water for hydroelectric dams that is topped up by the rain, or the sunlight that reappears every day for solar panels. Because nuclear power uses up radioactive fuel, it is not renewable in the same way.

Nuclear energy, however, is the second-largest source of low-carbon electricity in the world behind hydropower. Some researchers say it is essential for helping countries including the UK reach targets of producing all their energy without releasing greenhouse gases. This is because there is not yet enough renewable energy capacity to provide for all our electricity needs. Renewable power is also intermittent - for instance, wind turbines don't produce power when the wind doesn't blow (although large batteries to store this energy are improving all the time).

Nuclear energy is not without its issues. Most notably, it produces radioactive waste that must be transported safely to long-term storage, where it will not be disturbed for tens of thousands of years until the material is no longer a danger to human health or the environment. These challenges are ongoing.