Decom boom

Even if the nuclear market goes up and down, there are multiple new projects developing all over the world for conventional Pressurized Water Reactors (PWRs) and Boiling Water Reactors (BWRs), as well as development of the new Small Module Reactors (SMRs).

Konecranes vice president business unit nuclear in the US, Steven Waisanen explains that the most active regions are China, Russia, United Kingdom, Turkey and the Middle East, while in other places, like Germany and Italy, it has become less popular.

“Abu Dhabi bought two plus two units from Korea Hydro and Nuclear Staff (KHNP), which is the government of South Korea, and several other countries are looking to get a licence to build plants like Jordan and Saudi Arabia,” says Waisanen.

“In China they have three different 3.0 designs, the Areva EPR, the Westinghouse AP1000 and China’s own design.

“Russia has the VVER design reactor at 1,000 megawatts and they are exporting their design to other countries. For example, Russia built units for India, China and a new project for Turkey amongst other countries as well.

“So there are a number of projects ongoing such as in Finland with Fennovoima for a new plant. The project is still in planning stages as the company is trying to get the final approvals from STUK [the Finnish regulator] for the design of the facility.

“Even though in the UK it was supposed to start decommissioning existing nuclear power plants between 2016 and 2018, they are extending the licence and planning to do five new plants, such as Horizon and Hinkley C.”

Waisanen adds: “Horizon is looking to build new ABWR [advanced boiling water reactor] units to provide 5,400 MW at Wylfa [in Anglesey, Wales]. The new units will provide power to the grid to help replace the older units that will be shut down and move to decommissioning phase.

“The same goes for the new EDF PWR plants to be built at Hinckley C. All of these new plants will require new material handling equipment to meet the code and standards required to meet UK regulatory requirements.

“In the US, the business is focused on the decommission projects as there are two additional units, VC Summer 3 and 4 and Vogtle, which are on hold because of disputes regarding financial costs.”

Disaster Recovery

Headquartered in Shoreview, Minnesota, PaR Systems LLC is specialised in automated manufacturing and material handling equipment. Jeff Konop, engineering manager, says: “We recently built a Fuel Handling Machine for Fukushima power station and it has been installed to remove spent fuel from the storage pool for the Reactor 3. The reactor building was heavily damaged by a hydrogen explosion during the Great East Japan Earthquake in March 2011.

Tokyo Electric Power Company (TEPCO) installed a new superstructure over the Unit 3 Reactor Building, to provide both a new support floor to carry the fuel handling machine (FHM-1) but to also provide a cover to shield equipment and personnel from potential bad weather conditions and enclose the work area.”

The Fuel Handling Machine built by PaR Systems is a gantry type bridge with an integrated TensileTruss tool delivery platform. The TensileTruss provides extended reach similar to a telescoping mast, with inherent high lateral stiffness even though it is a platform suspended by wire rope. The lateral stiffness is needed to deploy tools that will operate underwater and perform specific clean-up tasks.

FHM-1 also has a traditional telescoping fuel handling mast commonly used for moving nuclear fuel at commercial nuclear power plants, as well as a 5t auxiliary hoist and high radiation resistant cameras. Hydraulic manipulator arms are mounted to the TensileTruss platform and are equipped with a suite of tooling supplied by Westinghouse and Toshiba for removal of both fuel and building debris from the spent fuel pool. The debris is a result of the destruction caused by the hydrogen explosion and collapse of the building roof. FHM-1 weighs 72t and was lifted by two large cranes during its installation in November 2017. The next step will be to test the equipment installation and then FHM-1 will be ready for live operations.

Another critical nuclear system delivery by PaR Systems (PaR) recently was the design and build of the Main Cranes System for the Chernobyl New Safe Confinement (Unshakeable Truss,).

The Main Crane System provides hoisting and remote tool delivery, again using PaR’s TensileTruss technology to provide the equipment necessary for the deconstruction and safe clean-up of the site.

Decommissioning Market

“The goal is to turn the former nuclear power plant property into a green field state once decommissioning is complete,” Waisanen says. “Some of the countries with the largest number of decommissioning or planned decommissioning projects are the United States, United Kingdom and Germany.

“Decommissioning plants still has many of the same requirements as operating plants, such as maintaining the equipment in the plant during the dismantling process, which takes roughly 20 years. These facilities even require new equipment as wel,l because the focus or purpose of the cranes has changed.”

Areva Nuclear Materials Director, D&D Site Acquisitions Geoff Wilde says, “The US went through a period that was supposed to be a nuclear renaissance when reactors were initially licensed for 40 years, and many expected to and did renew their licenses for an additional 20 years,” Wilde says. “Unfortunately, unexpected economic pressures have begun causing some facilities to shut down much earlier than planned, particularly in competitive generation markets. One major contributor is the reduction in the market price of natural gas by 75% from its peak. As a result, more utilities are finding themselves with sites that no longer generate electricity, but now need to be decommissioned. Since this is a task not within their core business, these shutdown site owners are seeking options.

“Thus, the US industry expects from 10 to 15 nuclear energy facility closures over the next 10 years, along with sites already undergoing shutdown procedures. There are nearly 100 US facilities in operation today.”

The nuclear industry has to efficiently organise to match decommissioning competencies with changing market needs, says Wilde. There are three options permitted by the NRC, adds Wilde: “The first one is to put the plant in what is called ‘SAFSTOR’ for 60 years before doing any decommissioning, and that has usually been the default choice by the utilities,” Wilde says. “Another option is to push towards Prompt DECON to immediately start the decommissioning process. The third option, ‘ENTOMB’, is not typically considered, but would be where the radioactive components are permanently entombed in concrete in-place and left asis on the secured shutdown reactor site.

“Thus, a question may arise for plants placed in SAFSTOR or for those, which could be shut down in the upcoming years—should they continue with SAFSTOR or should they opt for a Prompt DECON (decommissioning) solution?

“The inertia to overcome is that SAFSTOR has been the default, with risk embedded in traditional approaches to initiating Prompt DECON,” Wilde says. “New forces pushing the market toward Prompt DECON include: 60 years of SAFSTOR liability and management of end-of-life assets detract from site owners’ core electricity generation business; costs of used nuclear fuel storage management go from being incidental as part of electricity-generating operations to the only cost of the shutdown site that is non-revenue generating; public interest in accelerated clean-up of sites and availability of the property for reuse; local economic impact from loss of the formerly operating reactor site’s employment and tax revenues; and advancements in decommissioning technology and processes that improve Prompt DECON economics.”

The solution taken by Areva Nuclear Materials (ANM) is to partner with demolition expert NorthStar in a joint venture called Accelerated Decommissioning Partners (ADP). The purpose of this ADP joint venture is completing the final lifecycle stage of shutdown reactor sites using Prompt DECON and the combined core competencies of NorthStar and AREVA Nuclear Materials.

“A unique and significant aspect of the ADP decom business model is the complete ownership transfer from the reactor site owner to ADP,” Wilde says. “This transfer includes the reactor site, its NRC licenses, and used nuclear fuel management, including the independent spent fuel storage installation (ISFSI) and on-going storage inspections. NorthStar is the largest demolition and environmental abatement company in the world, and has more than 20 years of experience successfully completing commercial and government decommissioning and closure projects. As a subsidiary of the global company New Areva, ANM is the most experienced reactor vessel removal and used fuel management company worldwide, including D&D work at six US utility-scale nuclear reactors (BWR and PWR).

“Though separate from the ADP joint venture, NorthStar is using a similar ownership decommissioning business model for the Vermont Yankee nuclear power plant decommissioning in which ANM is performing as a subcontractor to NorthStar.”

Wilde adds that ANM continues to advance new decommissioning technologies and refine proven methods for efficiently handling nuclear materials. For example, the company has recently introduced advanced canisters that can accept and store used nuclear fuel after a shorter time in a reactor’s used fuel cooling pool.

“By moving the fuel earlier into storage, we can begin the reactor dismantling earlier,” Wilde says. “Segmenting, packaging and removing the radioactive reactor components and materials are some of the most challenging stages of a nuclear reactor site decommissioning.

“We are advancing our proven market leading technologies to accomplish these tasks more efficiently, too. Once these stages are completed, the remainder of the activities is fairly straightforward demolition and site remediation.

“Our nuclear materials handling capabilities combined with NorthStar’s demolition expertise enable us to offer the Prompt DECON option and decommission sites in about six years, significantly less time than the up to 60 years allowed under the SAFSTOR approach originally considered at many sites.”

In terms of challenges with decommissioning projects, Wilde highlights the lack of a national consolidated repository for the used fuel and high level nuclear waste. “The Department of Energy (DOE) has the responsibility to develop it,” Wilde says. “What the industry has had to do for many years is to safely move the used fuel to each reactor’s onsite dry storage facility (ISFSI), where it will remain until an off-site alternative is available.

“Even when a current nuclear plant is fully decommissioned and nearly the entire site is restored, the one part left is the independent spent fuel storage installation, which is safe, but still remains on the former site. The DOE is required by law to take ownership of the fuel and remove it, but without a repository, there is uncertainty of when it can be removed. This is one of the biggest challenges in the US decommissioning industry.

“Another storage option looked at for many years that may still become a reality, is where used fuel will first be moved to a consolidated interim storage facility and then to a permanent repository once available at a later date. This is a possibility that could happen in the next several years.”

UK based lifting and mechanical handling group SCX comprises three complementary businesses. One of these, SCX Special Projects, is the bespoke engineering division of SCX and solves mechanical handling and electrical control system problems in demanding sectors such as defense, energy, nuclear and large moving architectural structures such as retractable stadium roofs.

Nigel Montgomery, controls director at SCX Special Projects, says: “As system integrators, we apply all the technologies available to us, integrating them through a mechanical handling and control system design that meets all the project’s contractual and specification requirements.”

SCX Special Projects is involved in many current nuclear decommissioning projects, for clients including Dounreay Site Restoration Ltd, Urenco UK and EDF Energy. Its track record in nuclear dates back to 1999 with a crane for the UK’s first nuclear power station decommissioning at Berkeley.

Montgomery says: “We support the whole mechanical and electrical lifecycle of the design and are involved in lifting projects from the very early stages.

“We conduct feasibility studies to understand a customer’s needs, and what can be achieved with the available technologies. We can take a project all the way from initial concept, through to design and build, testing, and installation on-site.

“More than that, we can maintain the equipment for the lifetime of its operational use, until the decommissioning itself ends. It’s a full service, and it’s very uncommon to find a single supplier who can support the whole lifecycle entirely through its own in-house capability.

“SCX Special Projects also has an in house design and verification capability, plus experience in the Functional Safety aspects of safety critical applications.

Obviously, any collision or dropped load could be catastrophic, so all our nuclear projects include very strict nuclear-rated safety control systems.

“We also have a unique solution in the UK to protect against uncontrolled dropping of loads. It safely arrests the hoist drum within 30° of rotation, with a damped and controlled stop. It also allows electrical and/or mechanical recovery of the load, so that investigations and repairs can be made safely without having a suspended load to contend with.

“Our intellectual property lies in the overall design of the lifting solution, which includes mechanical engineering as well as the electrical controls. We provide the client with all the mechanical and electrical calculations and validations behind the design to prove how our solutions deliver to the required level of nuclear safety.

“SCX Special Projects finds that innovation in mechanical handling comes from making existing proven technologies work together in new ways. This is where disciplines such as electrical control and instrumentation (EC&I) play a huge part in the success and safety of the final solution, ensuring extremely high reliability and availability for our equipment.”

In terms of new control system technologies, Montgomery says that the nuclear sector favours tried and tested technologies with identifiable operational experience. Any new technologies or equipment used must undergo additional scrutiny and validation before its use would be accepted.

New Regulations

Waisanen says: “With the Fukushima accident, new standards were developed globally to address safety concerns regarding new and existing nuclear power plant designs.

“Many existing facilities are modernising their facilities to meet the new standards.

Some directly affect material handling equipment inside the plant. Konecranes has been able to develop unique and value added finite element analysis to qualify existing equipment for natural disasters and create new equipment that will withstand the worst case seismic, hurricane or tsunami and tornado events.

“Konecranes has developed a SuperSafe single failure proof design for handling nuclear spent fuel casks as well as other applications where safety is of the highest concern. We have developed multiple patents covering a wide range of features within our design to address critical safety concerns in the industry. We have also been introducing innovative technologies for the new equipment in the new design of plants coming to the market to address a more modular concept of producing nuclear energy.”

Waisanen adds that the new plant designs continue to be presented to regulators for approval addressing the new regulations.

“The key will be adherence to schedule in building plants as a substantial amount of capital is required for the construction of the new plants,” Waisanen says. “As with building capital investments, the longer it takes to commission the equipment, the more it costs buildup until the plant can start producing power. So the future is about building plants that are more modular, where the build cycle is easier to predict where a majority of the production is done in a controlled factory environment, and the total build cycle is significantly shorter.”

Waisanen says that new construction slowed after the Fukushima accident but is starting to pick up once again as countries look to move to a lower carbon emission solution in the power industry while simultaneously reducing costs to compete with rock bottom natural gas prices seen in some parts of the world. “As such there has been an influx of new opportunities to meet these new market demands for traditional power plant design as well as designs requiring lower water volume and higher safety requirements.”

Waisanen adds that Konecranes’ sales are going well for the nuclear market. “In 2017 the 50% of our business was for modernisation works and the other 50% was for new equipment in new plants or decommissioning plants so it’s a pretty good balance,” he says. “I think the energy race will be focused on what form of energy produces that is most cost effective per KW rate while producing the lowest possible carbon footprint. The nuclear power generation is certainly one of them.

“The key here is to building a plant to meet promised delivery schedule while meeting all safety and regulatory requirements so that the plant can move from a capital cost investment to an energy producing pay back.

“With new technologies entering the market, plants can now be built in places where high volumes of water are no longer required. These new SMRs will fill a gap in the market where the large plants are not feasible yet produce 500MW to 600MWs of power the same as a coal or natural gas fired plants.”