Block ip Trap

Clean Grid Alliance Applauds MISO for Comprehensive RIIA Study; More Work Ahead

04 Mar 2021

The Midcontinent Independent System Operator (MISO) presented a final report and key findings from its Renewable Integration Impact Assessment (RIIA), a years-long study of the impact of increasing renewable energy in the MISO footprint. The study evaluated the addition of renewable energy at various penetration levels - up to 50% - to identify challenges that may emerge in transmission, markets and operations, and offered potential solutions to remedy them.

“We commend MISO for their excellent comprehensive study and we appreciate the foresight MISO has had in getting ahead of the issues before they become problems,” said Clean Grid Alliance Executive Director Beth Soholt. “Renewable energy is here to stay, so putting forward a report that includes a number of next steps and further research that will help chart a course for further development of renewable energy in the Midwest and is just what we need. Clean Grid Alliance is excited to be a partner in figuring out these really tough challenges. We need MISO to be a leader because incremental change alone in transmission, markets and operations will not get us to the net-zero goals announced by many utilities. We need bold action, and call on MISO and its members to provide a grid that can reliably add the new resources needed to significantly reduce carbon intensity in the Midcontinent.”

Clean Grid Alliance was particularly pleased to see that achieving 50 percent renewable energy on the MISO system is not insurmountable, although the study indicated a significant amount of transmission in the north and western portions of the MISO footprint is needed. “Wind and solar developers are being asked to develop projects for utilities as well as corporate and industrial customers who are anxious to deliver low-cost clean energy to their customers and reduce their carbon footprint at the same time,” said Soholt. The Midwest has excellent wind and solar resources, but is lacking adequate transmission to deliver them. On the heels of the massive power outages in Texas, questions about how much renewable energy the system can handle has prompted even more questions. “Whether the system ‘breaks’ at 30 percent renewables is not the right question,” said Soholt. “MISO has done a great job identifying what needs to be done to prepare for the generation shift that is already underway, and we urge them to implement the solutions as quickly as possible.” 

Among the important conclusions identified in the study are:

  • More flexible resources will be needed, as well as market products and incentives for existing and future gas and storage and even renewables to offer their flexibility; 
  • More transmission and other emerging technologies will be needed to provide a stable grid capable of delivering power where it is needed; and
  • The region needs to move forward expeditiously to address these issues in a timely manner. 

CGA commends MISO for already beginning this work with the Long-Range Transmission Planning effort, the Resource Availability and Need effort, and the recent Reliability Imperative report. More work and coordination with all stakeholders will be needed as the region continues to prepare for the generation shift.  

Clean Grid Alliance encourages MISO to further study how storage and hybrid resources can help provide solutions to ramping, weak grid issues, and to reduce the overall need for transmission. “This is a one-step-at-a-time process, but time is of the essence. Technical work is needed to first ensure the grid remains flexible, reliable, and resilient as we add new resources,” said Soholt.

Clean Grid Alliance |