Overview

Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States.

Background

Domestic demand for electrical energy is expected to grow by more than 30% from 2009 to 2035. At the same time, most of the currently operating nuclear power plants will begin reaching the end of their initial 20-year extension to their original 40-year operating license, for a total of 60 years of operation. The figure below shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years (and new nuclear plants are not built quickly enough to replace them), the total fraction of generated electrical energy from nuclear power will begin to decline. The oldest commercial plants in the United States reached their 40th anniversary in 2009.

Projected nuclear power generation.

Sustainability in the context of light water reactors (LWRs) is defined as the ability to maintain safe and economic operation of the existing fleet of nuclear power plants for a longer-than-initially-licensed lifetime. It has two facets with respect to long-term operations: (1) manage the aging of hardware so the nuclear power plant lifetime can be extended and the plant can continue to operate safely, efficiently, and economically; and (2) provide science-based solutions to the industry to implement technology to exceed the performance of the current labor-intensive business model.

Light Water Reactor Sustainability Program

The LWRS Program is focused on the following three goals:

1. Developing the fundamental scientific basis to understand, predict, and measure changes in materials and systems, structures and components as they age in environments associated with continued long-term operations of the existing reactors
2. Applying this fundamental knowledge to develop and demonstrate methods and technologies that support safe and economical long-term operation of existing reactors
3. Researching new technologies to address enhanced plant performance, economics, and safety.

The existing U.S. nuclear fleet has a remarkable safety and performance record. Extending the operating lifetimes of current plants beyond 60 years and, where possible, making further improvements in their productivity will generate early benefits from research, development, and demonstration investments in nuclear power. DOE has partnered with the Nuclear Regulatory Commission and the Electric Power Research Institute to conduct the long-term research needed to inform major component refurbishment and replacement strategies, performance enhancements, plant license extensions, and age-related regulatory oversight decisions. The DOE research, development, and demonstration role will focus on aging phenomena and issues that require long-term research and are generic to reactor type. Cost-shared demonstration activities will be conducted when possible.

The LWRS Program consists of the following four primary technical areas of research and development:

1. Materials Aging and Degradation. Research to develop the scientific basis for understanding and predicting long-term environmental degradation behavior of materials in nuclear power plants. Provide data and methods to assess performance of systems, structures, and components essential to safe and sustained nuclear power plant operation, providing key input to both regulators and industry.
2. Advanced Light Water Reactor Nuclear Fuels. Improve scientific knowledge basis for understanding and predicting fundamental nuclear fuel and cladding performance in nuclear power plants. Apply this information to development of high-performance, high burn-up fuels with improved safety, cladding integrity, and improved nuclear fuel cycle economics.
3. Advanced Instrumentation, Information, and Control Systems Technologies. Develop, demonstrate, and deploy new digital technologies for instrumentation and control architectures and provide monitoring capabilities to ensure the continued safe, reliable, and economic operation of the nation’s operating nuclear power plants.
4. Risk-Informed Safety Margin Characterization. Develop and deploy approaches to support the management of uncertainty in safety margins quantification to improve decision making for nuclear power plants. This pathway will (1) develop and demonstrate a risk-assessment method tied to safety margins quantification and (2) create advanced tools for safety assessment that enable more accurate representation of a nuclear power plant safety margin.