The FINANCIAL -- N.Y. -- GE’s Energy Consulting business served as the lead technical consultant for the recent Minnesota Renewable Energy Integration and Transmission Study (MRITS), performed by the Minnesota utilities and transmission companies in coordination with the Midcontinent Independent System Operator (MISO), and directed by the Minnesota Department of Commerce. The study demonstrated that Minnesota’s power system can accommodate renewable generation, representing up to 40 percent of retail sales in total with certain upgrades to existing transmission. The study also found that even with these higher levels of renewables, the overall system could continue to operate essentially as it does under normal conditions today, according to General electric.
The study also determined that this level of renewable generation in Minnesota could be reliably achieved with only about 2 percent curtailment of renewable energy, often cited as a challenge when considering whether to develop renewables projects. When moving towards 40 percent renewable penetration on the Minnesota system, there is modest change in energy from Minnesota’s conventional generation.
“GE Energy Consulting’s findings will help Minnesota develop and continue to achieve its renewable energy strategies and goals,” said Minnesota Department of Commerce Commissioner Mike Rothman. “We appreciate Energy Consulting’s technical analysis, showing renewable energy is a viable and reliable resource to meet Minnesota’s energy needs.”
One of the concerns often raised with the introduction of high levels of renewable generation onto the grid is the impact on the grid’s stability and its ability to adequately respond to system disturbances. This study, along with several others conducted by GE’s Energy Consulting business, demonstrates that higher levels of renewable penetration do not negatively impact grid stability and further, can actually enhance resiliency when equipped with grid-friendly controls. The Minnesota study showed that wind and solar resources contribute significantly to voltage support and dynamic reactive reserves. Additionally, the fast response capabilities of wind and solar inverters can help with voltage recovery following a system fault.
This Minnesota study builds on several similar studies that GE’s Energy Consulting business has conducted across the United States and Canada over the past several years using GE’s PSLF* modeling software—including the recent study of the Eastern Interconnect (EI) of the U.S. for the National Renewable Energy Laboratory (NREL). That study considered the impact of 25 percent renewable penetration on frequency response on the EI system, finding that renewables at this penetration level could actually help with grid resiliency, according to General electric.
“While 25 percent renewable penetration on the Eastern Interconnection is an aggressive target overall, the fact that Minnesota’s system could reasonably accommodate 40 percent renewables penetration demonstrates the importance of evaluating the role renewable energy can play in the generation mix at regional and local levels,” said Doug Welsh, Technical Director, GE’s Energy Consulting business and GE project manager for the Minnesota study. “Not all electric power systems are created equal, and taking into account the unique aspects of individual systems can create a better understanding of the role renewable generation can play across the U.S. and around the world.”