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Why are nuclear power facilities renovating and expanding?

There are many reasons for nuclear renovation and expansion. But let¡¯s focus on four.

1. Increased electricity demand: We are using more and more electricity across North America. Why? The population is growing, new technology is using more power, and electric vehicles are replacing gas ones. That means we will need to generate and transmit more electricity. Doing so will require new and updated infrastructure.
   
   My home area¡ªOntario, Canada¡ªwill need a lot more power by 2050. A report by the?Independent Electricity System Operator says that Ontario may require up to?17,800 megawatts (MW)?of?new nuclear capacity?by then. This will help the province meet its clean energy goals. Ontario¡¯s plan to invest in more nuclear power puts it at the forefront of the global nuclear renaissance.
   
   
2. Low emissions: show that nuclear power has much lower carbon emissions than fossil fuels. It¡¯s clear that fossil fuels are being phased out. Policymakers, industries, and consumers all want other options. Many see new¡ªor updated¡ªnuclear power facilities as crucial for reducing carbon emissions and fighting climate change.
   
   
3. New technology: Nuclear power is changing fast. Soon, we will see these technologies in use. One example is small modular reactors (SMRs). They have many benefits. For example, SMRs use a standard design, take less time to build, and offer enhanced passive safety features.
   
   
4. Aging infrastructure: Many traditional nuclear plants are reaching the end of their useful life. Many in Ontario are 40 to 50 years old. For these older facilities, we can renovate¡ªor even expand them. It gives them new life.

As North American providers refurbish reactors and replace key components or build new power plants, they shouldn¡¯t overlook the buildings that support them. Now is also the time to rethink and upgrade these support nuclear power facilities. If we want safe, secure, efficient nuclear campuses, it¡¯s important to invest in a modern nuclear campus, which includes all its components.

What does all this mean for the future of nuclear sites?

Big changes need to happen ¡°outside of the fence¡±

Electricity providers are planning new stations to meet demand. Ontario plans to add up to . This includes four SMRs.

To add capacity at existing nuclear power facilities, major facility upgrades may be needed. They must make room for new reactors and the physical construction activities for the stations. That means they will likely need to tear down or move existing buildings and infrastructure on their nuclear campus. All this needs to happen while they keep the site safe and generating power.

When we think about the layout of a nuclear campus, we categorize facilities as ¡°inside the fence¡± or ¡°outside the fence.¡± Inside the fence refers to the nuclear power generation station itself. Outside the fence includes the buildings and infrastructure that support the safe operation of the reactors. There are a variety of buildings outside the fence. A nuclear power facility campus can¡¯t function without them.

These support facilities include:

• Offices and administration
• Training facilities
• Storage
• Maintenance
• Low-level radioactive waste storage
• Protective and emergency services
• Turbine buildings

To expand its nuclear power facility, providers will need to reconfigure today¡¯s campus or build a new one. It¡¯s complex. And that¡¯s probably an understatement.

When they add nuclear capacity and refurbish the stations, they also need to update or build new support facilities. They may need to demolish old ones.

Streamlining while maintaining design integrity

We are often brought in to apply our commercial industrial experience to these nuclear campus projects. The nuclear industry wants turnkey buildings delivered on strict deadlines and budgets. While these support buildings are outside the fence, they fulfill critical roles at nuclear sites. And they must meet rigorous standards. In design for nuclear power facilities, we must focus on design integrity, even when we¡¯re looking for cost-effective solutions.

Taking cues from our previous nuclear projects, we can summarize nuclear power facility support in four critical design values. Operability. Maintainability and flexibility. Redundancy. And safety.

These design values make up a strong framework that helps make nuclear campus facilities are resilient and well-prepared to meet future demands. Let¡¯s look at them one at a time.

1. Operability: Design customized to needs

Operability is about making sure the design supports the power provider¡¯s way of working. The outside the fence designs should support operations and efficiency.

For example, one provider doesn¡¯t allow its staff to use ladders in their facilities¡ªfor efficiency and safety reasons. An alternative is using temporary indoor scaffolding to reach critical controls and valves. That option requires more design, expense, and permits. Our solution: To support operability, we designed their infrastructure so that all the facility¡¯s valves, shut-off handles, and emergency controls are within reach when the operators are standing at ground level. Everything they need is four feet (1.2 metres) above the finished floor. When it¡¯s time to service a fixture, it¡¯s easily accessible¡ªnot 40 feet off the ground.

2. Maintainability and flexibility of support structures: Design for the long term

You can¡¯t just design to construct buildings for today, or even five years from today. These buildings will last decades. As designers, we¡¯re highly aware of the resources (and embodied carbon) invested in new buildings. It¡¯s no different for nuclear support buildings.

Support buildings are often used well beyond their intended lifespan. Here in Ontario, many of the buildings we¡¯re helping renovate are more than 40 years old. They have already been renovated¡ªmultiple times. Right now, we¡¯re renovating the heating, ventilation, and air-conditioning (HVAC) systems on several support facilities.

Unfortunately, many of the buildings built in the 1960s and ¡¯70s aren¡¯t easy to upgrade. Here is what we¡¯re facing: Mechanical rooms in basements. They¡¯re built around equipment that will need to be chopped into pieces to be removed. It¡¯s not easy.

To renovate these support buildings, we often need to demolish and relocate systems and rooms. And that¡¯s often expensive and difficult when building expansion isn¡¯t an option.

The lesson here applies to both renovations and new building designs. A long-term design mindset pays off. We need to design new support buildings to last, but also with enough flexibility so that they can be reused. And when we¡¯re able, we need to extend the life of reused buildings and improve their flexibility.

Designs should use future-proofing strategies whenever they can.?For example, let¡¯s look at the design for a new simulation space at a nuclear power facility. We know that over the course of four decades, the HVAC system is going to fail. It will be replaced multiple times. And climate change will influence a building¡¯s future system needs. A design that puts the HVAC deep in the basement, where access is limited, makes it hard to maintain.

But if we know this piece of equipment will need to be replaced in 20 years, we can put it on the roof or at ground level inside the building, with easy access for replacement or repairs through double or overhead doors. When the time comes, it will be easier for technicians to replace. You can remove a piece of equipment and replace it rather than demolish the equipment or building and infrastructure around it.

3. Redundancy for essential functions: Design for year-round operations

A nuclear campus must operate 365 days a year. Many of its outside-the-fence buildings are critical to its operation. Even with support structures, we need to design for redundancy. Take the nuclear campus sewage pumping station. If a building served by that pumping station needs to operate 24/7/365 and a pump goes down, what happens? Without backup, the building stops functioning, and that can have drastic effects across the site.

Redundancy applies in some unexpected ways, even in training. For example, one training building features control room simulators that look exactly like the reactor control room in the station. Built in the ¡¯70s, these simulators are exact replicas down to the furniture, the carpet color on the floor, the color schemes¡ªwith every knob and control in the same place as the real thing. These simulators have become critical for training to avoid human error. Operators must complete years of training to become certified. At one site where we have worked, these simulators operate more than 16 hours a day, nearly year-round. There is barely time for document filing, let alone supporting infrastructure downtime.

But these older training facilities are heated by steam. So, the aging steam pipes and valves are leaking and need to be serviced. When the building is shut down for repairs, sometimes for weeks at a time, training is halted. That¡¯s a real example of why redundancy is key. In this case, we need heating systems that can be supplemented with different heat sources and allow for temporary HVAC unit connections¡ªso that a building can stay operational even in these sorts of situations.

4. Safety is always number one: Design for the elements

Safety is the number one priority at nuclear sites. Designing to building and fire codes is just the minimum. It¡¯s true, support buildings aren¡¯t subject to the same high standards as the power station itself. However, we use operational experience from the stations and past projects to enhance the safety of systems in support facilities.

Our team is working mostly with clients in Ontario. And the nuclear sites are near the water. In Ontario, the winter weather can be unpredictable and dangerous. Ice storms and blizzards can cause slips, trips, and falls. Pathways and building accessways need to be designed to be easily cleared of ice and snow. If you¡¯re mounting equipment outdoors, it should be safe to access and maintained regularly. We developed a standard for one project that required the installation of all HVAC equipment on a housekeeping pad that¡¯s a minimum of four feet (1.2 metres) wide around the equipment perimeter. This allows operations staff to remove snow around the equipment. It also gives them a place to kneel and arrange their tools while performing maintenance.

Vital and resilient nuclear power support buildings

Support structures play a vital role in a nuclear power facility. They are not optional. Anytime the energy provider wants to add nuclear capacity on their existing campus, they need to consider the buildings they need to add, renovate, or relocate.

These buildings need to keep running while the nuclear power facility is operating. The complex, interconnected nuclear campus will only increase in importance in a new age of nuclear power.