COP26: CAISO helping drive global clean energy research, grid modernization for IBRs

The California Independent System Operator is part of a global group of grid operators working to drive global clean energy advancements and find solutions to modernize power grids in order to handle the influx of inverter-based resources, President and CEO Elliot Mainzer said Nov. 4 during the UN Climate Conference in Glasgow.

Power system operators are at the leading edge of transforming power systems to deliver net-zero electricity globally, said Fintan Slye, director of the UK's National Grid System Operator and chair of the CEO steering group of the Global Power System Transformation (G-PST) Consortium. G-PST, which CAISO is part of. The group was launched eight months ago at the Global Power Summit as a deep collocation between system operators and leading research labs globally to rapidly accelerate transitions to advanced low emission power systems.

"By brining that experience together with some of the leading research intuitions globally, we can dramatically accelerate the decarbonization of our power systems," Slye said.

Atmospheric carbon dioxide remained between 280 ppm and 300 ppm for about one million years, said Mark Foley, CEO of Ireland's EirGrid and G-PST member.

"It was 412 parts per million at the last record and it's heading onto another planet," Foley said about the rapid growth. "Electricity is at the front line in terms of the battle against carbon."

Inverter-based resource expansion

Technology improvements are needed to ensure a grid, which was designed for a different era, is modernized to accommodate all the renewable energy and storage that is coming online.

"As we're seeing in California, wind, solar and batteries are the leading new clean energy resources being added to electricity grids around the world," Mainzer said.

The rapid expansion of inverter-based resources creates a set of new reliability challenges, such as securing adequate inertia, stable voltage, system protection, black-start capability and the ability to ride through disturbances.

"Solving these challenges will require advances in technology, tools, operating practices and training," Mainzer said.

UNIFI research

G-PST members share common concerns about the challenges created by the ever-increasing quantity of inverter-based resources, which led supporting the Universal Interoperability for Grid-Forming Inverters (UNIFI) Consortium, Mainzer said. The UNIFI Consortium has the primary goal to design the clean reliable power grid of the future and enable any level of inverter-based resources and synchronous machines to work together.

G-PST supported the UNIFI Consortium's successful bid to receive a $25 million US Department of Energy award to future research.

G-PST and UNIFI will work together to answer the following questions to manage large quantities of inverter-based resources:

• How can we ensure inverter-based resources can safely interact with each other and synchronous machines as the grid evolves?
• What capabilities will inverter-based resources need to ensure clean, reliable, affordable power?
• What services will future high- inverter-based resource systems need?
• How will tools and models need to evolve to accurately monitor and predict high inverter-based resource grid behavior?

California clean energy goals

Senate Bill 100, passed in 2018, set a statewide goal of 100% carbon-free electricity by 2045. California met its interim 2020 target of 33% electricity from renewables two years early, Mainzer said.

"For a brief moment on April 24, 2021, 94.5% of electricity on the California Independent System Operator grid was from renewables," Mainzer said about breaking a record of 92.5% set a month earlier. "These were glimpses into the future of a very high renewable penetration."

In 2020, CAISO produced 33% of electricity from renewables, with the remaining coming from 37% natural gas, 12.2% large hydro and 9.3% from nuclear. By October 2021, the ISO's installed renewables included 60% solar and 20% wind.

Battery storage additions

"We're also adding lithium-ion battery storage capacity at unprecedented levels," Mainzer said.

CAISO had 250 MW of battery storage on the grid during the summer of 2020 which had grown to 1.915 GW by October 2021.

"And we're on track to have 3,000 MW by the end of this year," Mainzer said. "We're excited to be part of the global energy storage revolution."

CAISO is preparing to integrate significant quantities of additional clean energy resources over the next several years, as much as 15 GW by 2026 and 40 GW by 2032, mostly solar, wind and storage.

"As we take on this next phase of rapid renewable energy integration, we need to develop additional transmission capacity to deliver this power to consumers," Mainzer said. "We also need to coordinate market operations with our many partners across the Western United States who are also striving to achieve ambitious energy policies in a reliable and affordable fashion."