Conservation Voltage Reduction (CVR) Deployment in Lethbridge Electric Utility (LEU) Distribution Network

Lead Proponent

City of Lethbridge

Project Background

The City of Lethbridge Electric Utility (LEU) provides utility distribution services to over 42,000 customers ranging from industrial facilities to residential areas. The goal of this project was to increase the level of control in keeping end-customer voltage within the lower half of the Canadian Standard Association’s defined range, ultimately reducing electricity demand, consumption, and greenhouse gas emissions for customers in the City of Lethbridge.

Leveraging LEU’s already-installed Advanced Metering Infrastructure (AMI), newly implemented Conservation Voltage Reduction (CVR) technology would automatically and safely manipulate the distribution system’s operating voltage. This would in turn promote energy conservation and reduce customer electricity bills.

A pilot project in 2018 applied CVR technology to one of the city’s electric substations with the goal of demonstrating its effects and capabilities. The success of the pilot project prompted a scaling of the project to fully implement CVR throughout the city.

Results

Despite not quite reaching the initial anticipated energy savings goals, the project still saw both energy savings between 0.18% to 3.83% and greenhouse gas reductions between 750 and 5800 t CO2e. These savings do not reflect the full potential of CVR. With its inadequate decision-making and inconsistent operation, the software used, and its implementation methods have yet to reach maturity.

Through the project, the City of Lethbridge discovered they would require a complete re-orientation of its electric loads to properly utilize the full potential of CVR. This is because each substation distributes energy to a range of customers with different demand and load sensitivity. As a result of certain software malfunctions and questionable automated decision-making, it was decided that CVR is not a long-term viable option for achieving notable energy savings in Lethbridge.

In light of the project’s shortcomings, some features of the software proved to be advantageous. Namely the voltage outlier feature which helped reduce the system’s blind spots by identifying and analyzing problems that affect distribution.

Benefits to Canada

Full implementation of CVR technology saw reductions in greenhouse gas emissions of upwards of 5800 t CO2e in the City of Lethbridge. On top of that, reductions in electricity demand and consumption saved on energy costs for over 40,000 customers. The project also served as a case study for future CVR use, displaying specific nuances in AMI management and grid orientation that would be required to realize the technology’s full potential.

Next Steps

As of June 2022, CVR operation has been permanently discontinued. LEU is still actively looking for alternate, more efficient means of reducing greenhouse gas emissions.