If existing inventories of used nuclear fuel were recycled and repurposed as fuel for advanced fast reactors, it could generate zero-carbon electricity for Europe for up to 1000 years, according to international environmental campaign group RePlanet.

Report author Mark Lynas and RePlanet's Campaigns Coordinator Joel Scott-Halkes hug a canister of nuclear used fuel at the UK's Sizewell nuclear power plant (Image: RePlanet)

In its new report - What a waste: How fast-fission power can provide clean energy from nuclear waste - RePlanet says Europe's nuclear power reactors "have a long history of safe use, and have provided prodigious quantities of clean electricity for decades". However, it notes that they use less than 1% of the actual energy potential in the natural uranium used to make their fuel and irradiated fuel assemblies removed from reactors are considered 'nuclear waste'.

"While this nuclear 'waste' is not a serious environmental or health threat - it occupies trivial volumes compared to waste produced by other industries, and does not harm anyone if properly shielded and safeguarded - it does provide a political challenge, and is among the most oft-cited reasons for continued opposition to carbon-free nuclear power," the report says.

RePlanet says using this used fuel in a new generation of fast-neutron reactors would "eliminate it as a 'waste' concern via a carbon-free waste-to-energy process". It notes that most of the remaining leftover fission products would return to a level of radioactivity comparable to the original uranium ore within 200-300 years. "This means that current deep geological disposal strategies can be simplified and scaled back," it suggests.

The report found that using a calculation based mainly on current inventories of uranium, "there is sufficient energy in nuclear 'waste' to run Europe at current electrical power consumption" for between 600 and 1000 years.

It adds: "If unconventional uranium and thorium resources are considered in the global picture, nuclear fuel is essentially limitless: sufficient to supply a growing human civilisation with carbon-free energy for tens of thousands of years, and likely far longer".

The report notes that while the economics of fast reactors are currently unproven, if resources currently intended for deep geological disposal of used fuel were diverted instead into a fast reactor programme that would enable the re-use of that fuel, "this would turn a burden into a useful part of a legitimate circular economic activity".

Launching the report, RePlanet campaigners call on green parties of Europe to end their "dangerous and unscientific" opposition to nuclear energy. This, it says, is particularly important given the recent release of the Intergovernmental Panel on Climate Change (IPCC) Synthesis Report, which shows the world is rapidly running out of time to cut carbon emissions sufficiently to meet the Paris goal of 1.5°C. "RePlanet campaigners state that opposition to nuclear is tantamount to climate delayerism from fossil fuel corporations because it will increase carbon emissions".

"Current political narratives treat spent nuclear fuel like it is a waste product that needs to be buried underground, leaving a toxic legacy for future generations," said Mark Lynas, climate author and RePlanet co-founder. "Anti-nuclear campaigners never tire of repeating this mantra in their campaign to shut down nuclear plants irrespective of our climate emergency. However, we show in this RePlanet report that nuclear waste simply needs to be recycled efficiently in order to generate centuries of clean power for Europe and the UK. This material is not waste, it is fuel for the future."

"The IPCC has again made it extremely clear that we just have to get off fossil fuels, and that opposing clean energy technologies like nuclear puts the world on the path to irreversible climate breakdown," said RePlanet Secretary General Karolina Lisslö Gylfe.

RePlanet describes itself as "a network of grassroots charitable organisations driven by science-based solutions to climate change, biodiversity collapse and the need to eliminate poverty".