HomeNuclearPaving the way to safer and cost-efficient reactors

Paving the way to safer and cost-efficient reactors

It is vital that energy companies prevent past mistakes from affecting the next generation of nuclear power plants, writes Thomas Fink

In 2014, The Independent newspaper reported on an impending ‘nuclear crisis’ in the UK.

Unlike many other fears commonly associated with that expression, this was a crisis of age and the possible extinction of the country’s aging nuclear fleet.

At the time, all but one of Britain’s reactors was predicted to close in 15 years due to “concerns over their economic viability or safety” and fears circled the possibility of an energy black hole as the nuclear sector fulfills nearly 20 per cent of the country’s power demand. All reactors except the Sizewell B power station were operating beyond their original lifetime specifications.

Three years later, the conversation around the future of the UK’s nuclear reactors has continued, shifting focus to the approval of plans for a station at Hinkley Point and other potential new builds.

However, this discussion recently took a turn toward cost as government officials look to tighten their belts on new projects and potentially take a stake in these new developments.

In February, future plant developers were given the expectation that a 15-20 per cent discount would be required on the price of electricity compared to the à‚£18 billion ($23 billion) Hinkley plant in Somerset.

More than ever, those involved in the engineering, development, financing and regulation of nuclear reactors are finding themselves at an important juncture where safety and savings combined will determine the future of nuclear energy. While achieving both can be a challenge, materials and components that last longer and require less maintenance help to reduce the total cost of ownership (TCO) of reactors over their lifespans and can even keep them running longer without compromising safety.

The UK’s challenge

EDF currently has a fleet of 15 reactors, all of which began sending electricity to the grid in the 1970s and 1980s. Due to their age, inspection and maintenance are key issues for EDF, not just for nuclear safety today but for the likelihood of plant life extensions later. Today, 13 new nuclear reactors – including Hinkley Point C – are planned in the UK across six sites from the mid-2020s onwards, with a combined capacity of 18 GW.

As the UK must progressively replace large parts of its existing electricity generating capacity over the next two decades – and as it seeks to decarbonize the sector in line with its legally-binding climate goals – now is the time to implement the right long-term cost and safety solutions. It is imperative that energy companies have the foresight to prevent the same mistakes from affecting the next generation of nuclear power plants and the possible repercussions over the next 60 years.

Applying TCO to investments

While total cost of ownership is a common metric for evaluating purchase decisions in many industries, it is a less familiar term for a straightforward concept that should be common sense to specifiers in nuclear reactor projects.

TCO is an estimate to help purchasers weigh both the direct and indirect costs of an investment, painting a bigger picture of overall value. When long-term maintenance is a consideration, cheaper components that are less durable and require more frequent replacement can ultimately prove to be the more expensive option, driving up the TCO of a nuclear reactor.

For example, components such as electrical penetrations are critical to keeping radioactive particles within the reactors’ containment structures. These components often feature polymer seals that degrade as they age, requiring frequent replacements (and decontamination) every 20 to 30 years.

By comparison, a non-aging glass-to-metal seal qualified for 60 years of use without need for replacement or maintenance requires fewer replacements, saving in both labour and material costs for roughly 30 to 40 penetrations, which can add up to more than à‚£12 million in savings over the lifespan of a single reactor.

Additionally, arguments can be made that fewer parts replacements also generate less waste – every part that is removed from containment is decontaminated and therefore less cost will be associated with disposal.

When assessing TCO for a nuclear reactor – whether it’s a new build or an existing plant that requires updates to avoid a decommission – designers and engineers should work closely with potential suppliers to propose a checklist of requirements that include a thorough assortment of long-term cost-generators, such as labour and time required for component replacements, associated cleaning and decontamination solutions, waste management, training operators if replacements must be completed by plant personnel, downtime during the replacement processes, etc. The more thorough the assessment, the more complete the cost analysis giving a more transparent picture of costs over the lifespan of the reactor.

Safety still comes first

Of course, no TCO assessment is complete without assessing the risk of hazardous incidents should components prove to be lower in quality, performance or durability over time. The massive costs associated with nuclear reactor malfunction aside, the safety of nearby communities has to be paramount when designing a new reactor or upgrading existing plants.

In fact, the nuclear industry has been adapting and improving safety standards since the Fukushima meltdown in 2011. An important take-away from that incident is the role that aged components played in the lead-up to the explosion.

According to Fukushima operator TEPCO, the high temperature and pressure levels in the accident overstrained the reactor containment’s organic polymer seals and led to the hydrogen leakage and, finally, explosion. The Japanese Ministry of Economy has confirmed these findings.

With the recent rise in radiation levels stemming from the Fukashima incident as well as the detection of radiation on the western shores of the US, the whole world is reminded of the real and lasting costs that can be incurred when investments are not made in high-quality, extremely durable components.

Not only can component failures incur a huge price tag for recovery efforts, but they can also have devastating reverberations throughout the industry as a whole, jeopardizing much-needed investments in upgraded and beneficial technologies that could bring about a most cost-effective age of nuclear energy.

However, despite the incident, progress continues and glass-to-metal sealing technology provides an alternative that allows for safe conduction of electricity through the fire-protective, pressure-resistant and hermetically sealed containment walls of nuclear power plants. The technology is already being used around the world in both civilian and military reactors.

Is the future modular?

With more resilient components on the market, the nuclear energy sector could see the rise of small modular reactors (SMRs) as the preferred new build option. SMRs are different from a regular small reactor in the way they are constructed.

SMRs use both large and small components that can be manufactured or replicated in a factory and moved to the site by truck, train or barge. If enough reactors can be made in a single factory it is more cost-efficient in the long run, as the cost per unit of energy output can be considerably reduced below those of larger plants.

It has been well-documented that new generation larger reactors have had problems with being over budget and delayed with production setbacks, meaning that projects are not only late but are often billions of pounds over budget. This is often attributed to the difficulty of making them safe.

For example, Cambridge University academic Tony Roulstone likened the schematic planning of Hinckley to “building a cathedral within a cathedral”, going so far as to label it “unconstructable”.

It is clear that there is an argument within the nuclear industry that the future relies on the emergence of smaller reactors, especially in the western world. US company NuScale Power recently said it hopes to build a small modular reactor by the mid-2020s, and the UK government is inviting companies to design small-scale reactors and will shortly set out policy on the matter, with initial estimates stating that a SMR could be operational in the UK by 2030.

Striking a balance

Nuclear power is on the rise. With similar lifecycle emissions compared to all the major forms of renewable energy, nuclear power will play an important role in shaping the world’s future supply. Governments across the world are looking to the industry to solve some of the most pressing problems of climate change and how to meet growing energy demand and increase energy security, while reducing CO2 emissions.

The two biggest hurdles in the industry are cost and safety. After the distressing events at Chernobyl over 30 years ago, the Fukushima disaster was a timely reminder of the dangers involved in harnessing nuclear power.

That is why it is imperative that companies look to the technological advances made in nuclear fission and the wider industry to do what is absolutely necessary to strengthen safety standards and guarantee that future facilities – both large and small – are as safe as they can be for generations to come.

Thomas Fink is General Manager of the Nuclear Safety Division at Schott, a recognized authority for glass-to-metal sealing technology, especially with respect to its use in nuclear applications. He also is an Advisory Board Member of Ohio State University Nuclear Engineering Program in the US.