An analysis of how one utility’s TOU rate reduced electric usage, cost, peak load and greenhouse gas emissions.
This case study presents a GridX analysis of a Time-of-Use (TOU) electric rate implemented by a large East Coast utility. The primary objective of this analysis was to evaluate the impact of the TOU rate on electric usage, cost, peak load management, and greenhouse gas emissions. The findings indicate that the TOU rate led to significant positive outcomes, including an average daily electric load decrease of 2.5% during the rollout period. This observed load reduction is notable as it is comparable to, or even surpasses, typical results achieved through conventional utility energy efficiency programs.
A large East Coast utility faced the challenge of optimizing electric usage and reducing operational costs and environmental impact. To address this, the utility implemented a Time-of-Use (TOU) electric rate. This initiative aimed to achieve meaningful outcomes such as reduced electric usage, lower costs, decreased peak load, and a reduction in greenhouse gas emissions.
The utility partnered with GridX to ensure the success of its TOU rate rollout. GridX’s products enhanced the utility’s ability to plan, implement, and execute the TOU program efficiently and effectively by providing automation, reliable calculations, and better insights. The analysis included nearly 19,000 residential electric customers who were migrated to a TOU rate in 2024, with another 19,000 customers serving as a control group. Load reduction and shift were calculated by comparing historical usage from comparable periods in 2023 to actual usage in 2024, with adjustments for weather. GridX’s Data Science team grouped customers by historical usage patterns, identifying 5 distinct patterns.
Electric Load Reduction: An average daily electric load decrease of 2.5% during the rollout period, comparable to or better than typical results of utility energy efficiency programs.
Fuel Cost Savings: A projected $13 million reduced annual fuel cost based on the observed fuel cost reduction in the measured period.
CO2 Emissions Avoided: A projected 27,000 tonnes of CO2 avoided, equivalent to the annual CO2 output of approximately 6,000 cars.
Peak Demand Reduction: A potential 29.7 GWh peak demand reduction, enough electricity to power about 2,800 homes for a year.
LMI Customer Impact: Low and medium income (LMI) customers reduced their electric usage by 1.3%, reflecting their lower base usage and limited flexibility during on-peak periods.
Targeted Insights: Load reduction varied from 1-4% by usage pattern, enabling more segmented marketing and education to customers based on their behavior.
View all of the results and take a deeper dive into the partnership.
