The Great Plains Institute recently released A Road Map to Decarbonization in the Midcontinent Electricity Sector as part of its work with the Midcontinent Power Sector Collaborative, a diverse group of stakeholders including investor-owned utilities, merchant power companies, electric cooperatives, environmental groups, and state regulators.
The road map is the first-of-its-kind for any region in the US and was developed by the collaborative to provide utilities, policy makers, and stakeholders with a better sense of what will be needed to inform sound near-term decisions that position the region to meet the challenges ahead.
A central conclusion of the road map is that substantial decarbonization of the region’s electricity sector is achievable with current technologies when making reasonable assumptions about progress in the coming decades. The road map also concludes that decarbonization is not likely to happen on its own without concerted action by utilities and new policies. To get there, the region will ultimately need a combination of very-low and zero-carbon resources, such as wind, solar, nuclear power, and natural gas with carbon capture.
A multi-year modeling effort to explore different pathways to decarbonization
To explore how the region might decarbonize the electricity sector, the collaborative worked with an analytical team on modeling different pathways. This extensive, multi-year modeling effort utilized the FACETS model to project future changes in electric generation, capacity, and greenhouse gas emissions based on what we currently know about how electricity is produced and consumed in the Midcontinent region. To learn more about what went into the modeling and how exactly the Midcontinent region is defined, you can read the report here.
The modeling team ran dozens of scenarios that would result in a range of possible emissions from now until 2050. This blog highlights key scenario results that show pathways for decarbonizing the Midcontinent and include different cost and technology assumptions about the future.
Business as usual scenario
The graph below presents two scenarios that were deemed some of the most likely by participants in the collaborative, with the emissions range shown in gray. In one of these scenarios, the cost of renewable electric generation continues to decline, while gas prices follow moderate projections expected by agencies such as the US Department of Energy’s Energy Information Administration. In the other scenario, gas prices remain at low prices, while renewable costs follow a more moderate, but still reasonably-priced, trend.
The graph shows that while the full range of future emissions do include scenarios in which electric sector emissions could rise, both of the likely scenarios show dramatic reductions by 2050.
The emissions scenarios presented above are considered “business as usual scenarios” because they do not consider potential changes in energy or greenhouse gas policies that may be enacted in the future. And yet, without additional policies, the modeling does show a decline in electric sector emissions. This is due to recent trends that have seen a consistent growth in wind and solar generation, while the electric sector slowly moves away from carbon-intensive coal power plants and builds out additional natural gas capacity as a result of low natural gas prices. A graph of electric generation sources in recent years for the Midcontinent Independent System Operator (MISO), which manages the region’s power grid, shows this trend quite clearly.
Electric generation mix: possible futures
If these trends continue under business as usual scenarios, the electric grid is going to see much more generation fueled by natural gas than we’ve had in the past. Under a low gas price, moderate renewable price scenario, natural gas generation grows to provide the majority of electric generation by 2050, while wind power continues steady but moderate growth. In this scenario, solar power does see growth but never becomes a major source of electricity.
While the graph at the beginning titled “Midcontinent Region Electricity Emissions” shows very similar results for both likely scenarios, the method of achieving these results vary quite significantly. In contrast to the natural gas-reliant, moderate wind, and low solar scenario just presented, the “Low Renewables Cost, Moderate Gas Prices” scenario results in huge growth for solar energy, putting it at equal proportions to wind energy by 2050. This scenario also sees nuclear power plants holding steady to meet the need for baseload power without huge investments into new gas infrastructure.
Decarbonizing the electric sector by mid-century
The scenarios presented above project future emissions under the policies we have today. However, to achieve a substantially decarbonized electric system by midcentury, it is likely that additional policies will be needed.
A primary focus of the road map is to model what the electric sector might look like under policies that achieve 80 percent and 95 percent decarbonization. Doing so helps us to understand how much we might expect to need from each electric source and to determine potential challenges or issues that may arise.
The decarbonization modeling is policy neutral – meaning that it doesn’t matter if this is a single policy like a carbon tax, trading program, a market-wide carbon cap, or, as is most likely, a portfolio of many actions and policies at all levels of government.
The resulting generation mix under a policy that achieves an 80 percent reduction in carbon emissions from the Midcontinent electric sector is shown below. As in most scenarios, natural gas does see significant sustained growth through 2050. However, this scenario also sees larger growth in wind energy when compared to business as usual scenarios, as well as huge growth in renewables and energy efficiency. Another major difference between this 80 percent decarbonization scenario and business as usual scenarios is the complete decline of conventional coal power by 2045. By 2050, the only remaining coal power plants have been retrofit with carbon capture and storage (CCS) technology, which has been made economically feasible by the policy-driven demand for low carbon electricity.
Finally, a 95 percent decarbonization policy results in even more significant shifts in our electric system. In this scenario, even coal with CCS declines by 2040 but is replaced by natural gas power plants built with CCS capability. Gas with CCS becomes a major producer of electricity by 2050, along with wind, which may potentially be the largest source of electricity under a 95 percent decarbonization scenario. Energy efficiency and solar power are also significant resources in this scenario.
