Scientists have devised models of “super grids” that can sustain Caribbean electricity during hurricanes by researching schemes of interlinked grid systems to offset the impact of reduced solar power. This is towards improvement in reliability and resilience of the energy supply when storms occur too frequently.
When hurricanes approach the shores of tropical areas, “super grids” might become a salvation.
Islands in the Caribbean are beginning to look away from costly imports of fossil fuels and toward using their abundance of sun and wind for electricity generation. However, frequent hurricanes can dampen the solar energy generated. Researchers at DOE’s Oak Ridge National Laboratory developed a comprehensive modeling method to better predict the drop in electricity generation when these storm clouds overshadow solar panels. The team explored how those energy losses could be balanced out using super grids—a collection of interconnected grids that allow electricity to flow across island chains or between continents.
Lead researcher Rodney Itiki says this kind of planning for infrastructure is crucial to ensure continued, equitable access to electricity in the Caribbean’s 12 island countries and the U.S. territories of Puerto Rico and the U.S. Virgin Islands. For the historically underserved island residents, evacuation from the path of many hurricanes hammering the Caribbean each year isn’t an easy feat. The loss of the sun’s energy during hurricanes is likely only to grow increasingly important on islands such as Puerto Rico, which declared a goal of converting to all-renewable energy by 2050.
Modeling Energy Supply during Hurricanes
Itiki’s model can be used to understand the impact of hurricane clouds on any electric system. In this study, he and his team of experts in grid integration, renewables, and advanced computing methods used his algorithm to explore different grid connection approaches, modeling how each would affect the availability of electricity. It examined how the large hurricane would reduce power from known solar installations while traveling 10 possible paths over 10 to 14 days.
“This is one of the major contributions because, while designing the power system, we need to design it considering all of the possible cases—the most being the worst-case scenario,” said Itiki, a postdoctoral research associate with ORNL’s Power Systems Resilience group.
Researchers simulated how much power would be available during hurricanes if electric grids were connected by high-voltage cables on the ocean floor. To learn whether these super grids would balance energy flow among regions, the team modeled four different combinations : a standalone U.S. grid, a standalone Caribbean super grid tying all the islands together, a U.S. Caribbean super grid, and a super grid connecting the U.S., Caribbean islands, and South America.
The largest super grid configuration included 90 photovoltaic plants within the hurricane corridor, plus solar farms in places such as California and Brazil that are unaffected by these hurricanes. The model showed some solar plants losing as much as 88% of their generating capacity for two days while shaded by hurricane clouds.
Findings and Future Directions
They concluded that the US Caribbean super grid most improved the reliability of power. A Caribbean super grid on its own, in isolation, was least helpful due to the fact that hurricane trajectories tend to presumably match the chain of the islands. The addition of South America did not reduce power variations significantly since most solar installations are few on this continent. However, it might offer security energy with an alternate supply of power in the event that islands became disconnected from each other or from the US system.
Itiki was working toward a graduate degree when he became interested in an existing successful subsea link between the electric grids of the United Kingdom and Germany. He began researching the potential benefits of connections like that until a 2017 natural disaster narrowed his geographic focus.
“Shortly after Hurricane Maria hit Puerto Rico, I began contemplating the interconnection between Puerto Rico and Florida,” Itiki said. Maria left some Puerto Ricans without electricity for nearly a year.
Itiki first focused on wind energy during hurricanes. He has been investigating how a U.S.-Caribbean super grid might alleviate power slumps caused when hurricanes damage Puerto Rican wind turbines. After such improvements in turbine technology had been made to make it stronger, he examined how a surge of hurricane wind energy could be shared among the Caribbean, the U.S., and South America.
Next up, Itiki wants to integrate his solar and wind algorithms to explore how super grids might broadly boost energy reliability in both the Caribbean and on the mainland. For example, after a massive weather event in the U.S., could the Caribbean grid provide supplemental power to the U.S.?
The work has broad implications for U.S. independence from fossil fuels – and for reliably connecting renewable projects of all types. “I don’t believe people are designing photovoltaic [solar] plants and taking into account hurricane shading,” Itiki said. “Utilities are picking the sites with the maximum sun exposure, and now they need to include in this requirement the normal trajectory of hurricanes. If all the plants are located in Florida, and a hurricane passes through Florida, then it will create a maximum power valley.
Itiki said that more research is required to determine if laying undersea cables is both environmentally and economically viable. Yet, even in the absence of such interconnections, Itiki’s model provided a critical new tool for the estimation of solar energy during extreme weather and the planning of transmission systems to make up for the lack. Utilities could use the algorithm to prepare for when a storm knocks out or dims solar energy, using solutions like batteries or pumped-storage hydropower.
The impact and future directions of “super grids” in the Caribbean are expanded below:
The novel approach of super grids gives an indication of not only enhancing its resilience to hurricanes on energy supply but may also redefine the renewable energy landscape in the Caribbean. At the core, these different regions connected in robust electrical networks, islands could mitigate the intermittency from solar power because of storm clouds. These/these interconnectedness guarantees energy sharing and backup capabilities that ensures in times of otherwise unfavorable weather conditions, there is a steady and accessible electricity supply. Beyond this, super grids have implications for optimizing the aim of sustainable development and climate resilience at the global level and set precedence for similarly vulnerable regions across the world.
Looking ahead, supergrid deployments will bring considerable opportunities for green economic growth and caretaking. Besides offering higher security of energy supply, they also offer a strong impulse to the local economy, encouraging investments in renewable energies, creating jobs in their installation, maintenance, and innovation in the related technologies. They also open up pathways for strategic cooperation between Caribbean nations and international entities in knowledge exchange and capacity building in renewable energy technologies and grid management.
The scalability of super grids also holds promise for broader applications beyond the Caribbean. Researchers can investigate this model in different geographical contexts with variable climatic conditions and test its use in other hurricane-prone regions, such as Southeast Asia or the U.S. Gulf Coast. This could lead to a global mesh of interconnecting renewable energy grids for more resilience in the face of weather-related events and to expedite the transformation of the world’s energy toward a more sustainable future.
In a nutshell, super grids are such a defining moment in the search for resilient and renewable energy solutions. Further research and collaborative efforts in these initiatives can change the way societies prepare for and recover from natural disasters while assuring energy security, environmental sustainability, and economic prosperity for future generations.