Planning for extreme weather risks in energy systems
Climate and weather related disasters are having enormous and growing impact on our infrastructure systems. We need new tools to plan our infrastructure with these risks in mind. Here we report on a new approach for incorporating these risks in electric power systems design.
2020 shattered previously accelerating records for climate and weather related damages to US infrastructure. As a result, there is an urgent need to update energy system infrastructure planning. In our paper published today in Nature Energy, we present a framework to explicitly consider hurricane risk in the planning of electric grids using Puerto Rico as a case study. On September 20, 2017, Hurricane Maria made landfall in Puerto Rico. With wind speeds up to 155 mph (69 m/s), it led to one of the worst black-outs in the history of the United States. It is very challenging to plan an electric grid for hurricanes and still provide affordable electricity. And yet, recent science has projected that the intensity of hurricanes may worsen with climate change. Puerto Rico has been impacted by 13 named hurricanes over the last 25 years, so this means the future could be very expensive for the electric system.
There are many trade-offs in energy system planning including costs, emissions and resilience. Power plants are expensive and designed to last - wind turbines typically have a design life of 20 years and coal plants 50 years. However, governmental policies can change rapidly. Recent plans to reduce emissions have led to stranded assets, operable infrastructure that must be retired early due to unfavorable economic conditions. Also, the cost of wind, solar and storage have been decreasing rapidly. A number of groups have been studying the energy transitions that these dynamics will bring about. In our paper, we try to understand the effect that extreme weather will have on this planning for those regions on the front lines of climate-related weather disasters, like Puerto Rico.
Energy system models optimize power plant investments into the future to keep costs as low as possible. In our study, we simulate that every 5 years there will be a hurricane with the possibility of three different intensities. The hurricane wind speed is used to project damage to the electric grid infrastructure which is treated as unusable. The system then builds new infrastructure to be able to meet electricity demand. By considering combinations of hurricane intensities and probabilities, we are then able to project average electricity costs and examine how infrastructure investments vary. Our results show that hurricanes increase electricity costs by 32% based on historical hurricane trends and that transitioning to renewables and natural gas reduces costs and emission regardless of hurricane frequency.
But there are roadblocks to building our infrastructure back in a less costly and more resilient manner and these need to be overcome. The 1988 Stafford Act requires that infrastructure is rebuilt as it previously was after a natural disaster. Originally intended to prevent taking advantage of disaster relief funds, this has prevented Puerto Rico from making much-needed updates to their electric grid after Hurricane Maria. The past is not a good surrogate for the future and given that 2020 just set the record for climate and weather related disasters in the United States, we are entering a new world where infrastructure (and the economic and policy forces that govern it) will need to take explicit consideration of the climate forces impacting its resilience.
- Andres Clarens and Jeff Bennett