Rise of the radioactive robots
Posted on 11/02/2019
Sellafield is the birth place of nuclear power in the UK and when Calder Hall was connected to the grid back in 1957, it hailed the start of the nuclear revolution. Today, the UK has 15 reactors across seven plants, generating around a quarter of our electricity. Energy policy continues to be a contentious issue and although not everyone agrees, many consider the advantages of nuclear energy to be the clean, safe and efficient production of cheap electricity by comparison to fossil fuels. The main challenges of nuclear power are the decommissioning of its facilities and the safe export of arising radioactive waste. The absolute top priority of any organisation working in the nuclear industry is safety, and for an obvious reason: the consequences of getting things wrong could result in disaster, on a global scale.
It is Sellafield Ltd, set up by the Nuclear Decommissioning Authority (a branch of BEIS), which is the organisation responsible for managing the safe closure and deconstruction of the Sellafield site and its waste products. Decommissioning a site takes time. A lot of time. Upwards of 100 years to be (a little more) precise.
The first reactors at Sellafield were rushed into service back in the 1950s and many of the design and maintenance records were lost. Legacy planning really comes into consideration for later designs. “Although the engineering was of great quality, knowledge retention wasn’t part of the mindset in those days and the idea of decommissioning these facilities at a point in the future was not on the agenda.” says Sellafield’s Dr Xavier Poteau, who is leading a team to implement new technologies.
“One of the things the business is trying to do is find solutions that allow us to do the job in a faster, cheaper and safer way and this is where our interest in robotics stands.”
“We started with an empty toolbox and we are the first generation to have to tackle this. It has taken some considerable time, but the nuclear industry is opening up more and sharing its challenges.”
A large portion of the nuclear waste at Sellafield is stored underwater in so-called ‘ponds’. But what exactly is down there in the murky waters? Enter the robots. For over ten years, Sellafield has been using remote operated vehicles (ROV), a kind of robot submarine to monitor and survey the environment. The robots have evolved over time and new features allow them to manipulate and move items around. Each ROV is controlled via a tether for safety reasons. Xavier explains “we’re always asking the question ‘what if’ so this way we can cut the power if we have to or pull the ROV back if necessary.”
As well as the underwater ROV, Sellafield has adopted a number of fixed robotic manipulators to laser cut items into more manageable sizes, and for the sorting and segregation of waste. “We are still early days in our adoption” says Xavier. “A number of processes are still manual, painstaking and very time consuming.”
Aerial robotics (drones) are also being considered on the site to survey buildings. Special features have been added to measure radioactivity and ‘hot spots’. This removes the necessity to build scaffolding and have people working at height and minimises risk of exposure.
Sellafield have come a long way over the years on their robotics journey, “baby steps” as Xavier puts it. We learned to be more intelligent about the robotic solutions we might need and always consider off-the-shelf or modified solutions before engineering solutions from scratch. Sometimes equipment may become damaged over time. Now, it is often more acceptable (and far cheaper) to replace a modified off-the-shelf tool multiple times than creating a bespoke ‘space-engineered’ product designed to withstand the extreme environment where it might be deployed.
The business has also shown signs of ‘horizontal innovation’, the transfer of knowledge and technology from one sector to another, for example considering how the combination of imaging technologies and new robotic capabilities developed for other sectors (oil & gas, surgical etc) could be applied in the nuclear environment
Currently, Sellafield is collaborating with the University of Manchester to design and develop an autonomous, ground based monitoring robot called CARMA (Continuous Autonomous Radiation Monitoring Assistance) based on an off-the-shelf platform. CARMA has been setup to perform the monotonous and routine task of surveying floors and equipment ensuring there is no new contamination, freeing-up the health and safety specialists to focus more on the tasks which need their expertise.
So how are Sellafield procuring the best RAI technology suited to their needs? One example is Game Changers – an innovation forum run by Sellafield which actively seeks to engage with SMEs who can submit proposals to help solve some of their technical challenges. These new ideas and technologies help reduce costs, reduce risk and make operations safer whilst accelerating the safe delivery of decommissioning.
What impact has RAI had on employment? No net change in the business it seems. RAI technologies enhance the work performed by humans and Xavier says that cooperative working will likely lead robotic implementation in the short term on Sellafield site. “I don’t think the nuclear sector is planning an industrial revolution like the car industry. Robotics offers a great opportunity to fast-track our mission. It will allow us to remotely operate in areas we had limited options for but, the environment we’re operating in being simply too complex, we would always need human intelligence to finalise decisions.” Xavier believes their collaboration with local SMEs has already spurred new opportunities and created jobs within the supply chain.
For Sellafield, adoption of RAI technology is not a simple process and any potential implementations are scrupulously examined beforehand. Progress therefore is millimetric but the benefits are obvious: if these technologies enable safer, cheaper and faster operations in a complex and hazardous environment, then the investment will be well worth it in the long term.