DER Investments – Energy Affordability and Other Metrics
By Ida Weiss, Synapse Energy Economics and Greg Ehrendreich, MEEA – from NESP News, Feb. 2025
The project team of E4TheFuture, Synapse Energy Economics, and the Midwest Energy Efficiency Alliance (MEEA) is using the Distributional Equity Analysis (DEA) Guide develop two case studies in Illinois assessing how the costs and benefits of DER investments are distributed to different populations. The project is supported by staff from the Illinois Commerce Commission (ICC) and involves broad stakeholder input via Work Group meetings. A total of five meetings have occurred to date, covering stages 1-5 of the multi-stage DEA process shown in Figure 1.
Figure 1. DEA Stages Overview
The Project Team is looking retrospectively at the energy efficiency (EE) and beneficial electrification (BE) plans from two of the largest utilities in Illinois – Commonwealth Edison (ComEd) and Ameren Illinois Company (Ameren). Stages 1-4 were addressed for both the BE and EE simultaneously. The Project Team is now focused on stages 5-7, which are being staggered, starting first with the BE plan DEA (currently at Stage 6), followed by the EE plan in spring 2025.
Table 1. DEA Case Studies (Stages 2-3)
Stage 4 involved surveying and selecting DEA metrics, where the criteria used for selecting the metrics included:
- Measurable utilizing existing data;
- Available at the desired resolution (i.e. census tract, zip code, etc.);
- Tied to local jurisdictional equity goals;
- Focus on distributional equity impacts;
- Avoid overlapping with BCA metrics and other DEA metrics; and
- Have a direct causation-correlation relationship with the utility investment type being studied.
The Project Team took both a top-down and bottom-up approach for selecting potential metrics to present to the Work Group. For ComEd’s EE plan, available data included program participation, energy savings, and utility dollars invested. For Ameren’s BE plan, data included participation, utility dollars invested, and avoided emissions. Available data was then compared to a list of potential DEA metrics to assess feasibility, based on metrics provided in the DEA Guide. The proposed metrics in Table 2 were presented to the Work Group for feedback and discussion.
Table 2. Potential Metrics for the Two DEA Case Studies
Ameren BE DEA
The Project Team first focused on presenting metrics and results for the Ameren BE DEA. The Project Team narrowed down potential metrics based on data availability, Work Group interest, and the six criteria listed above. Work Group participants highlighted the importance of including metrics relating to jobs and employment, non-energy benefits (i.e. benefits not relating to energy savings), and health impacts. As a result of Work Group feedback, the Project Team added analysis on the locations of existing EV chargers, calculated emissions reductions, and an overview of Ameren’s BE workforce development plan.
The most recent December Work Group meeting focused on results for utility program investment, participation, emissions, and EV charger access for two key programs in Ameren’s BE portfolio: a time-of-use EV charging rate program and a program providing incentives for level 2 charger installations.
Based on Ameren data, an estimated 18,000 vehicles will participate in the time-of-use EV rate program, with 26% of estimated participation occurring in EIEC and LI communities, as shown in Table 3.
Table 3. Participation in Ameren’s TOU EV Program
Ameren estimates that 85% of all new chargers installed will be dedicated to EIEC/LI communities (roughly 4,800). Ameren’s EV charger rebate program includes funding for 60 publicly accessible chargers, as shown in Figure 2.
Figure 2. Participation in Ameren’s EV Charger Rebate Program
To better understand the baseline for existing public charger access in Illinois, the Project Team mapped the existing locations of the 837 existing publicly accessible chargers using data from the National Electric Vehicle Infrastructure program. Figure 3 shows the distance to the nearest publicly accessible charger by census tracts, with EIEC communities highlighted in teal. Overall, rural EIEC communities experience the least access to existing publicly accessible chargers at 13.9 miles from the nearest charger. The average across all Ameren is 7.4 miles.
Figure 3. Distance to Nearest Publicly Accessible Charger
Next Steps
By early March, the Project Teams will finish presenting Ameren results (specifically bill impacts) and summarize key takeaways. Future Work Group meetings (late March through May) will focus on the ComEd EE DEA analysis and results. The Project Team will finalize results in Q1 2025, with a full report on the two case studies expected in Q2 2025. More information is on the project website.