Wastewater Treatment Facility Energy Efficiency Project
Includes a Solar Array
Funding for this project provided by the American Rescue Plan Act of 2021
The goal of this project is to implement energy improvement measures for the Town of Hopkinton Wastewater Treatment Facility (WWTF). The improvements include:
- Installation of solar photovoltaic array for energy source
- Replacement of motors for two (2) blowers currently used for the aeration of the facility's lagoons.
Energy Audit Measures Improvements Implementation
In December 2021, an energy evaluation was performed by Process Energy Services (PES) for the Hopkinton WWTF site. As cost savings were developed, each measure was prioritized based on ease of implementation, cost effectiveness and ability for each project to support subsequent measures. The projects were categorized as energy conservation measures (ECMs) for projects that require a capital investment, operational measures (OMs) for fast payback improvements (1 year or less), and energy supply measures (ESMs) for improvements that may reduce energy costs without reducing energy consumption. Energy Management Practices (EMPs) were also developed.
In December 2021, an energy evaluation was performed by Process Energy Services (PES) for the Hopkinton WWTF site. As cost savings were developed, each measure was prioritized based on ease of implementation, cost effectiveness and ability for each project to support subsequent measures. The projects were categorized as energy conservation measures (ECMs) for projects that require a capital investment, operational measures (OMs) for fast payback improvements (1 year or less), and energy supply measures (ESMs) for improvements that may reduce energy costs without reducing energy consumption. Energy Management Practices (EMPs) were also developed.
As such, the Town of Hopkinton intends to implement certain energy measures, including the installation of a solar photovoltaic (PV) array to supply most of the power used at the plant. Additionally, motors for the two blowers will be replaced, as they have reached the end of their useful life.
Installation of Solar Photovoltaic Array
Installation of a solar PV array system will provide the treatment plant with energy supply measures (ESMs). The facility site includes a field next to the Operations Building that could be utilized for a solar PV array. The proposed system would be similar to an array recently installed at the Warner, NH WWTF.
Installation of a solar PV array system will provide the treatment plant with energy supply measures (ESMs). The facility site includes a field next to the Operations Building that could be utilized for a solar PV array. The proposed system would be similar to an array recently installed at the Warner, NH WWTF.
The Warner array consists of (378) 300-watt PV panels with 10 sub-arrays connected to 5 inverters. The maximum power of the system is 113 kW with annual production of 142,000 kWh. For the Hopkinton WWTF, the proposed system would be approximately 56 kW to better match the plant energy use after the proposed energy measures are implemented.
Replacement of Motors for Blowers
The wastewater treatment plant includes two blowers used for water treatment process used for aeration of the lagoons. The motors for the blowers have reached the end of their useful life. This project includes replacement of these motors for reliability and redundancy.
The wastewater treatment plant includes two blowers used for water treatment process used for aeration of the lagoons. The motors for the blowers have reached the end of their useful life. This project includes replacement of these motors for reliability and redundancy.