As AES Indiana prepares to power the future, we continue to pursue a balanced generation portfolio. The chart below summarizes our current and forecasted resource mix.

AES Indiana resource mix

AES Indiana’s Integrated Resource Plan (IRP) continues to move the company towards cleaner energy resources. The figure above shows how AES Indiana’s resource mix has changed over time.

Resource portfolio

The electric utility continues to evolve through technology advancements, fluctuations in customer consumption, changes in state and federal energy policies, uncertainty of long-term fuel supply and prices, and a multitude of other factors. Since the impacts these factors will have on the future utility industry landscape remains largely uncertain, AES Indiana evaluates the key drivers of various futures. Those drivers are natural gas prices, carbon tax, coal prices, AES Indiana load and the capital cost assumptions for wind, solar, and storage. The results included coal retirement dates, Demand-Side Management (DSM) targets and new resource economics, and a portfolio that mitigates risk and performs the best across multiple futures.

Retire of 630 MW of conventional generation by 2023

AES Indiana has determined that the cost of operating Petersburg Units 1 and 2 exceeds the value customers receive compared to alternative resources. Retirement of these units allows the company to cost-effectively diversify the portfolio and transition to cleaner, more affordable resources while maintaining a reliable system. On March 11, 2024, AES Indiana filed a request with the Indiana Utility and Regulatory Commission (IURC) for a Certificate of Public Convenience and Necessity (CPCN) to convert Petersburg Units 3 & 4 from coal to natural gas. If approved, AES Indiana will continue to power the needs of its customers through a diverse resource portfolio comprised primarily of natural gas, wind, solar and energy storage. Read more.

Competitively bid for 200 MW of replacement capacity

AES Indiana is currently seeking approval from the Indiana Utility Regulatory Commission to acquire a 195 megawatt solar project located in Clinton County, Indiana. Expected to be complete in 2023, Invenergy will develop the project and manage construction. Once operating, the solar facility will generate enough electricity to power more than 30,000 homes. 

Target ~130,000 MWh per year of DSM and energy efficient programs

AES Indiana plans to continue to be a state leader in Demand-Side Management (DSM) implementation and through an extensive valuation of DSM bundles, compared to supply-side alternatives, will target 130,000 MWh of DSM in the 2021-2023 plan.

Maintain safe, reliable, cost-effective generation at Petersburg

Several systematic changes in wholesale power markets are impacting the viability of coal in MISO; Petersburg Units 3 and 4, however, provide firm, dispatchable capacity. Maintaining those units preserves optionality in the face of great uncertainty over the next five years.

Energy resources and storage

Combined cycle gas turbine (CCGT)

CCGT combines a natural gas-fired turbine and a steam turbine to produce electricity more efficiently and with fewer environmental emissions than other thermal energy options available in Indiana today. 

Energy storage

The AES Indiana Advancion® energy storage array (AES Indiana Array) is the first grid-scale battery-based energy storage system (BESS) in the 15-state footprint of the Midcontinent Independent System Operator (MISO). This 20M MW/20 MWh system improves reliability in a city that is one of the most innovative in the United States for implementing energy technology. Read more.

In the future, AES Indiana envisions additional energy storage devices, which will be used for other purposes including wind resources for grid stability as well as free-standing energy storage for peak-demand generation.

Utility mercury and air toxic standards (MATS)

AES Indiana has invested in new and upgraded environmental controls at its Petersburg generating station and converted all of the units at its Harding Street Station to natural gas to comply with new Utility Mercury and Air Toxic Standards (MATS) set by the Environmental Protection Agency (EPA). Read more.

Harding Street station

AES Indiana stopped burning coal at the Harding Street facility in February 2016 and refueled the units to natural gas. These conversions are part of AES Indiana's overall MATS and waste-water compliance plan for its power plants and will eliminate the need for a coal pile and ash ponds. Read more.