By Brian Hoffamn, Energy Efficiency Circuit Rider
The California Rural Water Association in partnership with National Rural Water Association and the United States Department of Agriculture has implemented a program to assist water and wastewater utility systems to evaluate and lower their energy consumption and costs. This Energy Efficiency Assessment considers current and past energy use, identifies the primary energy-consuming components, and identifies methods to lower energy use and costs. The concept of this assessment is to outline energy efficiency projects or operational changes that identify potential electrical savings.
In February of 2025, Brian Hoffman, Energy Efficiency Technician, performed an on-site Energy Efficiency Assessment of the Ponderosa Basin Mutual Water Company (MWC) water distribution system. Three 15 hp booster pumps lift water from the lower pressure zone to the main storage tanks. The three booster pumps were identified as an area of improvement and upgrades, which include updated pump controls and removal of incorrectly installed variable frequency devices (VFDs).
The VFDs were configured to detect and operate within a small pressure variation within the distribution system, which indicated that the two 120,000-gallon water storage tanks needed to be filled. After assessing the operation of the VFDs and information provided by the system operators, it was determined that the VFDs were installed incorrectly.
The following recommendation was provided to the water system to reduce power consumption by the booster pumps:
- Remove incorrectly installed VFD’s.
- Remove obsolete electrical control panels and replace them with updated panels.
- Install a new pressure switch or pressure sensor.
- Install soft start controls on each booster pump.
In April 2025, the recommendations contained in the Energy Efficiency Assessment Report were implemented and all upgrades were fully online by May 2025.
Upon receipt of the May 2025 power bill, the water system had saved approximately $3,374.00 when compared to the May 2024 power bill. To date, Ponderosa Basin MWC has saved approximately $15,000.00 over the last 5 months compared to the previous operating months in 2024. These savings have been used to add further improvements to the booster station and communication with the water storage tank level transducer, allowing the booster station to function and operate automatically.