Power plants that balance nuclear and renewable energy can increase revenue from the electricity market and reduce variable operating and maintenance costs, according to Argonne scientists.
Nuclear power plants usually run at full capacity or not at all. However, power plants have the technical ability to adapt to changes in energy demand and thus better accommodate renewable energy sources such as wind or solar power.
Researchers from the Department of National Energy (DOE) Argonne National Laboratory and the Massachusetts Institute of Technology recently explored the benefits of doing so. If nuclear power generates power in a more flexible way, the researchers say, electricity generation can reduce electricity costs for consumers, allow the use of more renewable energy, improve the nuclear energy economy and help reduce greenhouse gas emissions.
The team explores the technical constraints on flexible operations on nuclear power plants and introduces new ways to model how these challenges affect how the power system operates. “Flexible nuclear power operations are ‘win-win-win’, lower operating costs of the power system, increase revenue for nuclear plant owners and significantly reduce restrictions on renewable energy,” the team wrote in the Applied Energy article published online April 24.
Audun Botterud, a major energy systems engineer at the Argonne Energy Systems division, however, has been pushed for the first time, “this study evaluates and demonstrates the potential value of flexible nuclear operations in realistic power systems in the United States that are challenged by high variability in renewable energy generation . ”
This study helps to eliminate the long-standing view that nuclear power plants must operate in “baseload” mode, generating power at maximum rated capacity whenever they are online. The nuclear plant can even respond dynamically to hourly electricity prices and second-to-second frequency regulation requirements, the team found. Power systems that include renewable energy must be more flexible to balance supply and demand at any time. Nuclear operators in France, Germany and other countries are familiar with this approach, but less so in the United States.
The researchers developed mathematical representations of operational constraints caused by physics arising from the dynamics of nuclear reactors and fuel irradiation cycles in Applied Energy articles and companion papers, published in Nuclear Technology. The interdisciplinary team then combined a new approach with a power system simulation model to evaluate the overall cost of the power plant, market prices and revenues generated for the power plant, assuming different levels of nuclear flexibility.
“Nuclear power plants are governed by a different set of principles compared to other generators, and our approach enables representation of this relationship in the analysis of power systems and electricity markets,” said Francesco Ganda, principal project researcher and principal. nuclear engineer in the Argonne Nuclear Science and Engineering division.
By being flexible, plant operators can reduce the overall operating costs in the power system. For example, operators can produce less nuclear power whenever renewable energy is widely available. Nuclear plants can then exploit their reserve capacity to sell valuable “operating reserves”, or the ability to quickly change power output to help network operators balance supply and demand when unexpected events occur, such as power plant failures or errors in demand estimates.
This flexibility can increase the profitability of nuclear plants by increasing revenue from the electricity market and reducing variable operating and maintenance costs. Overall, the flexibility of nuclear plants can also help integrate more wind and solar resources and reduce fossil fuel energy production and associated carbon dioxide emissions.
Jesse Jenkins, graduate researcher at the MIT Energy Initiative, noted how the researchers’ approach and modeling studies “gave us a tool to further explore the potential benefits of flexible nuclear operations to work together with larger parts of the variable source of renewable power plants on the track it leads to low-carbon electricity supply. “