What is nuclear energy (and why is it considered a clean energy)?
The power of the atom has been at the heart of electricity generation for more than half a century. Now nuclear fission – the process by which nuclear energy is used to generate electricity – looks set to support the future of clean, net zero energy systems globally.
Nuclear energy has been part of the global energy mix since nuclear reactors first started producing power in the late 1950s.
From its heyday in the 1960s to the late 1980s, nuclear power’s popularity has risen and fallen – and often been a source of controversy. Today it plays a role in helping to provide clean, low-carbon electricity and could be pivotal in our efforts to reach net zero by 2050.
Nuclear power stations work in a very similar way to coal- and gas-fired power stations, but the science behind the nuclear production process is much more advanced.
In a nuclear reactor, a reaction is driven by the splitting of atoms – a process called nuclear fission – where a particle is fired at an atom to split it into two smaller atoms (and some additional neutrons). The neutrons released hit other atoms, causing them to divide and release more neutrons. This is called a chain reaction and the whole process creates masses of heat.
Nuclear reactors generate heat, which is removed by a circulating fluid, such as water, and turned into pressurised steam. This steam is then forced through turbines that turn electrical generators to produce electricity.
Webmaster: Thianphalit Leelamanee M51 No.55
References: https://www.nationalgrid.com/stories/energy-explained/what-nuclear-energy-and-why-it-considered-clean-energy
Unlike many renewable energy sources, power from nuclear energy can be generated 24 hours a day and isn’t dependent on the weather, like wind and solar power tend to be.
Because of this, nuclear power is more readily available to meet energy demands, which helps to lower the carbon intensity of the electricity supply during times when other renewable energy sources might not be as readily available.
Some new-generation nuclear power stations are now certified for 80 years of operation – far longer than a gas- or coal-fired power stations and many renewable installations. However, there are a number of significant expenses to consider, including upfront expense, decommissioning costs and storage costs of depleted fuel and other materials. They also require a lot of maintenance over their lifespan.
In an emissions sense, nuclear power is considered to be clean. It produces zero carbon emissions and doesn’t produce other noxious greenhouse gases through its operation.
The lifecycle emissions of nuclear energy (emissions resulting from every stage of the production process) are also significantly lower than in fossil fuel-based generation.
Nuclear fuels, such as the element uranium, are not considered renewable as they are a finite material mined from the ground and can only be found in certain locations. But nuclear power stations use a miniscule amount of fuel to generate the same amount of electricity that a coal or gas power station would (1 kg of uranium = 2.7 million kg of coal), so they’re considered a reliable source of energy for decades to come.
There are concerns around what to do with spent fuel from reactors, as there’s still no definitive way to dispose of it indefinitely without risk. However, although the reactors and housing remain untouchable for considerable lengths of time when a nuclear site is decommissioned, a new reactor can be built on the site itself
As the UK and US aim for net zero by 2050, the mix of electricity generation will change. Nuclear energy is likely to play a role globally in helping nuclear-capable nations achieve these goals.
In the UK, the construction of Hinkley Point C in Somerset has marked the current government’s intention to have nuclear as a pillar of its energy mix. Sizewell C – a sister plant to the active B station – is currently under consultation, with a proposed generation of 3.2GW. As of 2021 in the US, there are plans to ‘uprate’ existing reactors to increase their generation capacity, while two new reactors in Vogtle, Georgia, are expected to come online in 2023.