by Nick Fitzmaurice
In our previous issue of Down to Earth, I introduced the concept of the energy transition as we decarbonize local and global energy systems to address the climate crisis. This transition includes numerous interrelated components. Previously, I tackled electrification, and in Part 2 of Montana’s Energy Transition, I will be diving into electricity decarbonization. Look for future installments of Montana’s Energy Transition in our subsequent Down to Earth publications, when I will dive into demand-side management (DSM), efficiency measures, transmission infrastructure expansion, power sharing across the West, and other pieces of the energy transition!
Upgrading to Renewables
To truly decarbonize Montana’s energy system, fossil fuel power plants must be thoughtfully retired and replaced with renewable electricity generation. Then, as electrification eliminates direct fossil fuel combustion for energy, the electricity we consume will contain no direct greenhouse gas emissions. The longer utilities wait to decarbonize generation portfolios, the more financial risk they will incur with fossil fuel assets. Securitization, enabled by a bill from the 2021 Montana Legislature, offers a viable financing mechanism for utilities to refinance debt on stranded generation assets, easing the economic impact of shuttering fossil fuel plants. Unfortunately, the financial burden faced by utilities and ultimately passed on to ratepayers will only increase the longer utilities drag out this transition.
Where fossil fuel plants are retired, it is important to invest in the affected communities. Recently, the state legislatures of Colorado and Michigan created the “Just Transition Office” and the “Office of Worker & Community Economic Transition,” respectively. A similar office could be created within the Montana Department of Labor and Industry to guide the economic and community transitions in fossil fuel-dependent communities across the state. Already, the Colstrip Impacts Foundation offers grants for economic development, workforce retraining, and community adaptation in the Colstrip community. Puget Sound Energy has invested $10 million into this fund, and Avista Energy has donated $3 million for transition. The other Colstrip owners have not invested in community transition. This funding, along with $4.7 million in federal dollars from the Partnership for Opportunity and Workforce and Economic Revitalization (POWER) Initiative to retrain affected workers, remains largely untouched by the Colstrip community.
Replacing fossil fuel generation infrastructure requires a monumental buildout of renewable generation infrastructure and associated grid integration technologies. Montana’s greatest renewable energy potential is in our untapped wind resource, and the state also has extensive opportunity to build out both distributed rooftop and utility-scale solar. In 2022, wind and solar produced more electricity for NorthWestern Energy customers than NorthWestern’s share of the Colstrip power plant, and current buildout of these renewable resources has only scratched the surface of what is possible. Additionally, existing dams can be upgraded to increase their generation capacity, such as the recent upgrades at the Ryan Dam near Great Falls. Unlike coal and methane gas generation plants whose operations can be scaled to follow demand variations, renewables are dependent on the real-time availability of wind, solar, and hydrological processes (though dams provide relatively stable electricity supply). Integrating this renewable-powered grid with short- and long-term energy storage solutions such as electric batteries and pumped hydro (elevating water to store energy using the potential energy of gravity) can capture energy when it is available, ensuring electricity is reliably dispatched when Montanans need it.
In addition to utility-scale renewable electricity generation, the clean electricity grid of the near future will integrate numerous decentralized components and advanced technologies for optimal functionality. At the grid level, operators must accept the end of a decades-old large-scale centralized generation asset paradigm. It is completely feasible to reliably run the electric grid on variable renewable resources, but it will require new practices and more advanced systems. A major example of this shift is the idea of grid “inertia,” where the mass of large spinning turbines at centralized power plants provide stability to the grid. These resources are “grid forming,” because they establish the voltage and frequency of oscillating electricity on the grid, while variable renewables are traditionally “grid following,” dependent on a pre-established voltage and frequency to seamlessly feed electricity into the grid. However, grid-forming inverters are an available technology that enable reliable control of low-inertia power systems based solely on renewables. This technology is already well-integrated into isolated island grids such as on the Hawaiian islands.
Distributed energy resources (DERs) such as rooftop solar can further contribute to energy supply, while also bolstering efficiencies on the grid. When electricity is generated near where it is consumed, transmission losses associated with transporting electricity long distances are virtually eliminated. DERs are devices that consume or produce electricity, potentially also encompassing electric vehicles, smart thermostats, and home batteries. Innovations such as Virtual Power Plants (VPPs), as piloted in several applications across the country, can harness DERs to turn the conventional electricity grid on its head through this more flexible and resilient electricity supply. VPPs rely on decentralized DERs, utilizing a network of batteries (such as residential electric vehicles and battery walls) to store electricity when it is abundant. Advanced software and control systems then dispatch electricity when and where it is needed.
Another huge benefit of renewable electricity generation is that it does not require fuel; while coal and methane gas plants consume constant fuel supplies (constantly polluting) to maintain operations, renewables simply require initial construction then natural processes maintain steady power generation. Therefore, not only does the energy transition eliminate the costs of fuels (passed to ratepayers), but this transition enables additional load reduction by eliminating the energy needed for fossil fuel extraction, processing, and transportation.
Transitioning our massively interconnected electric system that spans the entire continental U.S. and can never be shut “off” poses real challenges along the way as we move from the established system to the end-state fully-renewable system. Realistically, this process will unfold over the next several decades, with the intention of fully decarbonizing the energy system as soon as possible. How rapidly we can accomplish this transition is constrained by real technological deployment and project implementation bottlenecks, but there are ample opportunities for acceleration. It is therefore imperative that we get to work. Both the current and end states are viable from a functional standpoint, so the real challenge of the energy transition isn’t designing that final state, but ensuring functionality and reliability throughout the mid-transition.
This article was published in the March 2024 issue of Down To Earth.
