Intro to Nuclear Power

Describe the Neutron Multiplication Power

It is a method for telling whether a reactor is subcritical, Nuetral, or super critical. Divides the current count of neutrons by the previous generation

PWR Vs BWR

PWS: Has more mechanical stress, keeps contimation inside of the main loop, more common

BWR: Has a simpler design, Boiling water carries contamination outside of main loop (to the turbines)

What major issues occur after a fission reaction

heat byproduct, high radioactivity (releasing beta and gamma rays), Chemical radioactivity

Describe how energy is produced, how trasnformers operate, and how it’s delivered to your home.

1. Heat is generated, which boils water, moves a turbine, and the turbine moves a generator. A rotating magnet moves inside a coil of wires, inducing electromagnetic induction.
   2. Theres too coils in a transformer with a conductor in the middle. The ratio of coil determines whether the voltage goes up or down

Describe the function of the Nuclear Regulatory Commission (NRC) in regulating and licensing nuclear power plants, and power plant operators.

The NRC's primary function is to regulate and license nuclear power plants and their operators in the United States, ensuring public health and safety, promoting common defense and security, and protecting the environment.

Describe the four types of ionized radiation in a Nuclear Power Plant

1. Alpha Radiation: Particulate. 2 Protons+2 neutrons (Helium Nucleus), very low penetrating ability (stopped by skin), hazardous if inhaled
   2. Beta Radiation: Particulate. High Speed electrons + protons, Moderate penetrating ability (stopped by thin sheets of metal), can cause skin burns
   3. Gamma radiation: Energy Wave, Photons, Very high penetrating ability, can go through the human body, requires lead or concrete to block
   4. Neutron energy: Made up of neutrons, Particulate energy, Very high energy, dangerous because it can activate materials in reactor, very high penetrating ability

Alpha Radiation

Particulate. 2 Protons+2 neutrons (Helium Nucleus), very low penetrating ability (stopped by skin), hazardous if inhaled

Beta Radiation

Particulate. High Speed electrons + protons, Moderate penetrating ability (stopped by thin sheets of metal), can cause skin burns

Gamma Radiation

Energy Wave, Photons, Very high penetrating ability, can go through the human body, requires lead or concrete to block

Neutron energy

Made up of neutrons, Particulate energy, Very high energy, dangerous because it can activate materials in reactor, very high penetrating ability

Describe ALARA

It stands for “As Low As Reasonably Achievable”, it’s a safety principle in the nuclear field that aims to minimize exposure to workers and the public to the harmful parts of nuclear power generation.

Aims to decrease 1. Time spent exposed, 2. increase the distance from radiation source, 3. and use high levels of shielding

Describe the subcomponents of a nuclear reactor

• Containment Building:

  • Thick, reinforced structure surrounding the reactor vessel.

  • Purpose: Prevent release of radioactive materials; acts as the primary barrier for safety.

• Reactor Vessel:

  • Houses the nuclear fuel (usually uranium) where fission occurs.

  • Contains the core coolant that transfers heat produced by fission.

• Pressurizer (in Pressurized Water Reactors – PWRs):

  • Maintains water in the reactor loop under high pressure to prevent boiling.

  • Ensures stable coolant flow and temperature.

• Steam Generators (PWRs):

  • Transfer heat from the reactor coolant to a secondary loop of water, producing steam.

  • Keeps radioactive water separate from the turbine loop.

• Turbine-Generator:

  • Steam from the reactor (or steam generator) spins the turbine blades, converting thermal energy into mechanical energy.

  • The generator then converts mechanical energy into electricity via electromagnetic induction.

• Condenser:

  • Cools and condenses spent steam from the turbine back into water.

  • Uses a cooling medium (like water from a river, lake, or cooling tower) to remove heat.

• Cooling Towers:

  • Release waste heat from the condenser into the atmosphere.

  • Large towers allow evaporative cooling, reducing water temperature for reuse in the condenser loop.

What is the Containment Building in a nuclear reactor?

A thick, reinforced structure surrounding the reactor vessel. Its purpose is to prevent the release of radioactive materials and acts as the primary barrier for safety.

Describe the function of the Reactor Vessel.

It houses the nuclear fuel (usually uranium) where fission occurs and contains the core coolant that transfers heat produced by fission.

What is the purpose of the Pressurizer in Pressurized Water Reactors (PWRs)?

It maintains water in the reactor loop under high pressure to prevent boiling and ensures stable coolant flow and temperature.

Explain the role of Steam Generators in Pressurized Water Reactors (PWRs).

They transfer heat from the reactor coolant to a secondary loop of water, producing steam, and keep radioactive water separate from the turbine loop.

How does the Turbine-Generator produce electricity in a nuclear power plant?

Steam from the reactor (or steam generator) spins the turbine blades, converting thermal energy into mechanical energy. The generator then converts this mechanical energy into electricity via electromagnetic induction.

What is the function of the Condenser in a nuclear power plant?

It cools and condenses spent steam from the turbine back into water, using a cooling medium (like water from a river, lake, or cooling tower) to remove heat.

Describe the purpose of Cooling Towers in a nuclear power plant.

They release waste heat from the condenser into the atmosphere. These large towers allow evaporative cooling, which reduces water temperature for reuse in the condenser loop.

• Spent Fuel Pools:

  • Description: Deep pools of water at the reactor site where used fuel rods are initially stored.

  • Purpose: Water cools the fuel and provides radiation shielding.

  • Advantages:

    • Excellent cooling and shielding.

    • Allows decay of short-lived radioisotopes, reducing heat and radiation over time.

  • Disadvantages:

    • Limited capacity; pools can fill up at older reactors.

    • Requires continuous active cooling; if cooling fails, overheating is possible.

• Dry Cask Storage:

  • Description: After several years in spent fuel pools, SNF can be transferred to sealed, heavily shielded casks stored on-site.

  • Advantages:

    • Passive cooling (no need for active pumps).

    • Robust containment; resistant to natural disasters and accidents.

    • Frees up space in spent fuel pools.

  • Disadvantages:

    • Still stored at the reactor site (temporary solution).

    • Security concerns due to potential for sabotage or theft.

• Proposed Geologic Repositories (e.g., Yucca Mountain):

  • Description: Deep underground facilities intended for long-term disposal of SNF.

  • Advantages:

    • Long-term isolation from humans and environment.

    • Reduces risk at reactor sites.

  • Disadvantages:

    • Political and public opposition has delayed implementation.

    • Expensive and technically challenging to construct and monitor.

Spent Fuel Pools

Deep pools of water at the reactor site where used fuel rods are initially stored.

Purpose: Water cools the fuel and provides radiation shielding.

Advantages:
- Excellent cooling and shielding.
- Allows decay of short-lived radioisotopes, reducing heat and radiation over time.

Disadvantages:
- Limited capacity; pools can fill up at older reactors.
- Requires continuous active cooling; if cooling fails, overheating is possible.

Dry Cask Storage

After several years in spent fuel pools, Spent Nuclear Fuel (SNF) can be transferred to sealed, heavily shielded casks stored on-site.

Advantages:
- Passive cooling (no need for active pumps).
- Robust containment; resistant to natural disasters and accidents.
- Frees up space in spent fuel pools.

Disadvantages:
- Still stored at the reactor site (temporary solution).
- Security concerns due to potential for sabotage or theft.

Proposed Geologic Repositories

Deep underground facilities intended for long-term disposal of Spent Nuclear Fuel (SNF). An example is Yucca Mountain.

Advantages:
- Long-term isolation from humans and environment.
- Reduces risk at reactor sites.

Disadvantages:
- Political and public opposition has delayed implementation.
- Expensive and technically challenging to construct and monitor.