Nuclear power plants are getting smaller and smaller

For a long time, nuclear power plants have represented a huge amount. Large-scale and complicated nuclear engineering is expensive and has a long construction period. Once the schedule is delayed, it means overrun risk. Nuclear engineers are solving these problems by reducing the size of nuclear reactors. The future small nuclear reactor may be only 1/3 of the size of a conventional reactor and can be completed in the factory and transported by truck or ship to the site for assembly.

Compared with conventional large-scale nuclear power plants, this type of small modular reactors (SMRs, Small Modular Reactors) with modular design, modular system plant prefabrication and field modular assembly means lower cost and easier construction and installation. The construction cycle is shorter and more secure and flexible.

The United States was one of the first countries to propose the concept of a small reactor, and the small reactor has always been one of the key research and development priorities of the United States. In recent years, after experiencing major tardiness and severe overruns in the construction of large-scale nuclear power projects, the U.S. government has favored new types of low-cost nuclear technologies including small reactors. In the United States nuclear energy revival plan advocated by Trump, the small heap will also play an important role.

Small module piles that can be transported by ships, trucks or trains

Conventional nuclear power plant reactor power is usually more than 1000 MW (1MW = 1000KW, 1KW = 1000W), but the power of small reactors is only 300 MW or even lower. For small countries and regions with weak electricity demand, weak power grid infrastructure, or power supply and heating in remote areas, seawater desalination, and offshore oil production, small reactors are considered excellent choices.

When former President Barack Obama took office, the U.S. government has always provided "high-profile" support to the small research and development wave. NuScale Power (NuScale), which is funded by the U.S. government, is at the forefront of the competition for landing small piles.

NuScale is a company dedicated to the commercialization of small modular reactors and is headquartered in Portland, Oregon. In 2014, the U.S. Department of Energy and NuScale signed an agreement to provide them with $217 million over five years to fund the design research of SMRs. On December 31, 2016, NuScale filed a SMRs design certification application with the United States Nuclear Regulatory Commission (NRC), which is also the first historical SMRs design certification application submitted to the NRC. NRC's scheduled review period is 40 months. Once issued, the design qualification is valid for 15 years, and a power plant can be built and operated with a construction permit application (COLA).

The NuScale small modular reactor is based on proven pressurized water reactor technology and its modularity is very distinctive. Due to the integrated design concept of the reactor structure, NuScale integrated the main equipment of the nuclear steam supply system—core core, control rod drive mechanism, regulator, and steam generator—into one module, thereby realizing a small reactor. Modular manufacturing, transportation, installation and refueling.

According to official website data, each NuScale module has a thermal power of 160 MWt and an electrical power of 50 MWe. The cost is lower than US$5,100/KW. The modules can operate independently or together with other modules to form a multi-module configuration. A NuScale power station can accommodate up to 12 modules. Since each NuScale module has its own containment and reactor systems and specific turbine generator sets, in a nuclear power plant equipped with multiple modules, the refueling of a single unit can be performed without affecting the normal power generation of other units. .

Each NuScale module (containing a reactor and steam generator in a cylindrical containment module) is approximately 76 feet high (approximately 23 meters) and 15 feet wide (approximately 4.6 meters). This design makes it easy to ship, truck or Train shipment. Although a simplified version of the traditional light water reactor, the SMRs have new and excellent safety features. Since both the reactor and the containment are placed in the underground pool, the water acts as a cooling medium and the reactor operates under natural circulation. It also has a passive safety system that can automatically shut down the reactor or cool the reactor without human intervention, even in the event of sustained power loss (such as a tsunami-induced power loss in the Fukushima nuclear accident).

In addition to the traditional light water reactor fuel, the NuScale company developed a small reactor that can also use MOX fuel.

The NuScale plan's first SMRs nuclear power plant site was selected at the Idaho National Laboratory (INL). The owner was UAMPS and Energy Northwest operated. If all goes well, it will start generating electricity in 2026. Although this is nearly ten years away from now, once the US Nuclear Regulatory Commission approved its SMRs design program, NuScale can establish supply chain and third-party manufacturing processes, and acquiring customers and promoting reactors will also become fast and easy. Of course, the siting of nuclear power plants still requires the adoption of additional regulatory approvals.

In addition to the United States, NuScale plans to operate the first 50MW small-scale power plant in the UK by the mid-2020s. The company had made a conservative estimate that by 2035, there will be about 55-75 GW (1GW = 1000 MW) of small reactor power demand worldwide - equivalent to 1,000 NuScale power generation modules.

Is the reactor even more economical because it is smaller?

NuScale's construction cycle for each module is about 3 years, which makes it easier to raise funds and investments can be paid more quickly. The company estimates that even if a power plant has 12 modules in the top grid, it will cost about 3 billion US dollars. In contrast, Westinghouse’s two AP1000 units at Vogtle, Georgia, were initially expected to cost US$14 billion and then increase to more than US$20 billion.

According to statistics of the International Atomic Energy Agency (IAEA), around 50 SMRs in the world are in the development stage of concept design, design certification, and application permission. Some of them are under construction: Argentina's CAREM integrated PWR, China's HTR- PM high temperature pebble bed gas cooled reactor and Russian KLT40s floating nuclear power station.

If early projects can be successful, the realistic possibility of large-scale construction of small nuclear power plants will be greatly increased, thereby reducing the upfront costs and risks of the nuclear power industry. On the other hand, we cannot know the true economic benefits of these small nuclear power plants until they are proven to be practical. In particular, what is the economics of small reactors compared to low-cost natural gas? The substantial reduction in initial investment does not necessarily mean that their electricity costs are low.

Ryan Fitzpatrick, deputy director of the Third Way Think Tank Clean Energy Project, told the MIT Technology Review that if it were to build a smaller nuclear power plant, the cost of electricity per megawatt-hour would not necessarily decline. Companies must save costs through other processes. These efforts can be shorter construction times and lower management costs with new designs. Neil Todreas, a professor at the Department of Nuclear Science and Engineering at the Massachusetts Institute of Technology (MIT), said that the key to lowering costs is to set up factories to mass produce such reactors.

However, this will face the “chicken-and-egg” problem: Building these factories requires a lot of orders to obtain financing, but it is difficult for the company to obtain these orders until the company can reliably produce a low-cost reactor.

The MIT Science and Technology Review also pointed out that since the Trump administration’s budget proposal has drastically reduced the US Department of Energy’s nuclear power projects, whether the company can obtain the remaining US$47 million is still unknown. In fact, some Republican lawmakers in a letter in May this year urged Trump to support the development of SMRs. They stressed the imminent competitive pressures from China and Russia.

In addition, some people are concerned that nuclear reactors may become new nuclear proliferation risks when they become smaller and increase in number.

The Union of Concerned Scientists has raised some doubts about the safety and security of nuclear power plants in reality. They pointed out that a widely distributed, but small number of reactor networks may make the proliferation of nuclear materials even more Difficulties, among other dangers, may be used to make dirty bombs.

In the end, it remains to be seen whether small modular reactors will be the ideal or most economical form of nuclear power generation. “But in a country where it is almost impossible to build any new nuclear power plant, it is the technology that will allow the entire industry to move forward again,” Todreas said. “I cannot be sure whether the small module reactor will be in the United States in the next few decades. Build on scale or completely replace large power stations. But in the short term, they are very important for the healthy development of the nuclear industry in the United States."

LED Emergency Bulb

rechargeable bulb,emergency led bulb, led bulb

Jiangmen City Pengjiang District Qihui Lighting Electrical Appliances Co., Ltd , https://www.qihuilights.com