In order to address climate change, there is increasing urgency to develop what’s known as a decarbonized power grid. Currently, electricity generation is responsible for about one-third of the US carbon emissions, since most of the electricity distributed by the power grid is generated by fossil fuels such as natural gas and coal. A decarbonized power grid would instead rely on renewable energy sources, such as solar photovoltaics and wind turbines. The consensus among experts is that the best path to decarbonized electricity country-wide is to incorporate many different forms of renewable energy resources into our grid. This will require a substantial restructuring of the grid’s architecture. For example, the grid was originally designed only to provide one-way distribution of electricity from power plants to the users. As a result, enabling rooftop solar panels and small-scale wind turbines to produce and feed electricity into the grid will require a large change to the distribution system. Additionally, to overcome the fact that some renewable electricity sources are only available at specific times or under specific conditions, such as solar power, the decarbonized grid will need to be able to store energy efficiently.
In a recent study, a team of researchers at Dartmouth College investigated how these proposed structural changes might affect the resilience of the power grid. Resilience here refers to how well the rest of the grid is still able to function when one or some of its components are disrupted. The researchers studied how such an updated power grid might be able to withstand disruptions, such as from extreme weather events or even nefarious attacks, in the performance of some of its components.
They used novel techniques from the field of mathematics called graph theory to model the proposed changes in the power grid. In particular, hetero-functional graph theory provides a way of modeling the different capabilities of the various components of the power grid and how the performance of each component affects the rest of the grid. This graph can model the ways in which electricity flows between different users and electricity sources, and the ways in which a disruption somewhere in the grid affects the rest of the grid. The researchers found that as they added more features of a decarbonized grid (such as efficient energy storage or distributed generation), the structural resilience of the grid increased. This suggests that moving towards a decarbonized grid in this way will not only help reduce our carbon emissions, but will also provide us with more robust and reliable electricity distribution. Especially as we face the uncertainties of unpredictable, extreme weather events, this increased resilience will be of utmost importance.
This work was pursued at the Thayer School of Engineering at Dartmouth. The project was led by Dakota J. Thompson, a PhD student studying energy systems engineering, along with Wester C. H. Schoonenberg and Amro M. Farid.
Managing Correspondent: Anne Hébert
Popular Press Source: Engineering study shows renewable energy will enhance power grid’s resilience