Why This Matters & Key Findings
THE GENERATION PORTFOLIO TRACKER
Five Ways the U.S. Electricity Generation Fleet Has Changed
The U.S. electricity generation fleet has evolved considerably over the past decade but not uniformly across states. Some have expanded both capacity and generation, others have increased utilization of existing resources, and still others have added capacity despite declining generation.
Between 2014 and 2024, U.S. electricity sales increased 5.6% and net generation grew 5.3%, while installed capacity expanded 13.0%. These differences raise an important question: How have individual state generation portfolios evolved relative to electricity demand?
ScottMadden’s U.S. Generation Portfolio Tracker examines these trends across all 50 states and the District of Columbia, identifying five distinct pathways.
Five Distinct Portfolio Pathways
The five pathways classify states by comparing 10-year changes in net generation and installed capacity against changes in electric sales. These pathways describe how generation and capacity have changed relative to electric sales rather than assessing the adequacy or efficiency of individual state generation portfolios. The table summarizes each pathway’s characteristics and key findings.
Note: Outpaced indicates growth exceeded electric sales growth by more than five percentage points; Tracked indicates growth was within +/- five percentage points of electric sales growth; Lagged indicates growth fell more than five percentage points below electric sales growth.
One finding cuts across the five pathways: 44 of the 50 states and the District of Columbia (86%) reduced power-sector CO₂ emissions between 2014 and 2024, despite following very different trajectories in generation output and installed capacity.
A Changing National Generation Mix
The national generation mix shifted substantially between 2014 and 2024. Coal’s share of electricity generation declined by 23.5 percentage points, while natural gas gained 15.9 percentage points, and the combined share of wind and solar increased by 10.7 percentage points. Over the same period, the share of electricity generated from carbon-free resources increased from 32.6% to 40.8%, an 8.2 percentage point gain, while power-sector CO₂ emissions declined by 29.1%, nationally.
While these national trends highlight broad changes in the U.S. generation fleet, they do not capture the different ways individual states have expanded capacity, changed generation output, and shifted their resource mixes.
Three States, Three Different Paths
Michigan, Wyoming, and South Dakota illustrate how different relationships between electricity sales, generation, and capacity can lead to contrasting outcomes.
MICHIGAN | UTILIZATION-LED
More Generation Without Significant Capacity Expansion
Between 2014 and 2024, Michigan increased net generation by 16.3% while installed capacity grew just 0.8%, despite a 4.2% decline in electric sales. Blended capacity factor increased 7.6%, and the state transitioned from a net electricity importer to a net exporter.
2014–2024 Growth
2014–2024 Growth
WYOMING | CAPACITY-AHEAD
More Capacity, Less Generation
Wyoming presents a striking contrast. Installed capacity increased 25.0%, while net generation declined 18.1% and electric sales remained nearly flat. Blended capacity factor fell 34.0%, and net electricity exports decreased from 30.1 million to 21.0 million MWh. Despite adding capacity and generating less electricity, Wyoming remained a substantial net exporter.
SOUTH DAKOTA | PORTFOLIO EXPANSION
Rapid Growth and a Shift to Net Exports
South Dakota increased net generation by 89.8% and installed capacity by 81.7%, far exceeding the 10.4% growth in electric sales. Blended capacity factor also increased 7.2%. This expansion coincided with a transition from a net electricity importer to a net exporter, shifting from approximately 2.2 million MWh in net imports to 6.4 million MWh in net exports.
2014–2024 Growth
Different Pathways, Similar Shifts in Generation Mix
Despite following three distinct portfolio pathways, Michigan, Wyoming, and South Dakota share a common trend: all three increased the share of electricity generated from natural gas and wind while reducing coal’s share.
Change in Net Generation Share by Resource (2014–2024)
Note: Figures represent percentage-point changes in each resource’s share of total state net generation between 2014 and 2024.
Yet the outcomes were markedly different. Michigan increased generation with little additional capacity, Wyoming expanded capacity while generating less electricity, and South Dakota experienced substantial growth in both. These contrasting results illustrate how similar shifts in generation technologies can accompany very different patterns of fleet growth and utilization.
What Path Did Your State Take?
ScottMadden’s U.S. Generation Portfolio Tracker offers an interactive view of all 50 states and the District of Columbia.
Explore how your state’s generation portfolio has evolved, compare trends across states, and examine the data behind the five pathways.
Looking Ahead
This article is the first in a potential series. Future articles may explore how insights from the Generation Portfolio Tracker can be applied to challenges like large-load siting, decarbonization economics, and resource adequacy.
Note: This analysis will be updated annually once EIA publishes its final state-level generation, capacity, and emissions data. EIA typically releases final data for the prior year in the last quarter of the current year.