Climate change is expected to disrupt thermal generators around the world in multiple ways. The impacts of today’s climate on nuclear power-plant cooling are already felt in Canada. For example, one of the nuclear stations operated by Ontario Power Generation (OPG) on the shores of Lake Ontario is directly affected by seasonal climate fluctuations and their impacts on lake conditions, because it draws its water from the surface of the lake. The Pickering station recently experienced several episodes of unwanted blooms of Cladophora algae during periods of sustained high lake temperatures. In 2007, OPG had to shut down one of its reactors and reduce its power output because of clogged screens and filters in one of its water intakes. Climate change can also favour aquatic invasive species, such as zebra mussels, which stick to, and clog, water intakes and outlets. Overall, the risk to OPG facilities of higher water temperatures and other climate related hazards remains relatively low because its nuclear stations have large design margins. However, should new nuclear or thermal power-generation assets be commissioned in Canada, rising temperatures could become an important design consideration for cooling systems.
To strengthen their assets and operations against climate change related impacts, Ontario Power Generation (OPG) implemented adaptive measures in 2016, and subsequently released their first ever climate change plan more recently in 2020. Thermal power plants have large cooling needs, usually met by using nearby water or outside air. Climate change represents a significant challenge for these cooling processes, as it changes the baseline conditions, such as air and water temperature. To meet the challenge, the power sector must pay greater attention to technologies and design options that reduce the vulnerabilities arising from changes in regional climate.
This case study highlights various challenges and respective solutions implemented by three companies around the world. In Canada, Ontario Power Generation (OPG) invested in equipment to prevent clogging of water-intake structures due to ice particles suspended in the lake during freeze/thaw transitions. Then in 2020, OPG released its first ever climate change plan, which commits to using nature-based protection measures, such as, building wetlands to mitigate against flooding, wildfires and other extreme events. Beyond updating traditional technologies and processes, they will continue to integrate climate science and modelling into their investment decision and engineering processes, when considering future design and asset upgrades.