University of Minnesota
Minnesota Technical Assistance Program

Wastewater Treatment Plant Project: Energy Efficiency & Renewable Energy Generation

Project Background

A new Minnesota Department of Commerce, Minnesota Pollution Control Agency and MnTAP project, funded through a grant from the U.S. Department of Energy, aims to increase energy efficiency (E2) in Minnesota municipal wastewater treatment plants (WWTP) and scope opportunities for onsite power generation. The project will run through 2017.

The primary goals of the project are to:

  • help wastewater facilities lower operating costs through improved energy efficiency, and
  • provide up-to-date information to help facilities and city staff make informed decisions.

Wastewater treatment is a highly varied industry in Minnesota, both in the amount of energy consumed and the selection of treatment operations and equipment. Across the U.S., WWTPs are responsible for 1.5% of U.S. electrical consumption. Energy is one of the largest contributors to plant operational costs, and has the greatest potential for cost reduction. MnTAP is looking for treatment plants to participate in a range of efforts to improve plant energy performance to reduce costs.

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Upcoming Workshops:
  • Date TBD - GreenStep Cities Follow-Up Session – Wastewater Treatment Benchmarking

Benefits of Participation – what can you get

  1. ENERGY STAR® Portfolio Manager® score – This is an energy benchmark for mechanical wastewater plants that compares your energy performance to plants nationally to identify operating cost reduction potential. This score accounts for differences in hydraulic and organic loads, climate and other factors and has been validated for plants larger than 0.6MGD (although we believe the model is likely to be useful for smaller plants also).
  2. Energy Assessments – MnTAP will conduct assessments at 10 mechanical wastewater plants and would consider assessments for aerated pond systems. These assessments:
    • Can evaluate current operations to identify energy efficiency and cost saving opportunities as well as possible ways to streamline operations and address maintenance issues
    • They can evaluate portions of planned expansions and plant modifications by working with your design engineers to look at capital investment vs. energy cost over the life of the plant to identify the most cost effective options.
    • Deliver energy reduction solutions for voluntary implementation.
    • Have no assessment fees and no regulatory burdens.
  3. Biogas Utilization Evaluations - If you produce biogas through anaerobic digestion, or are interested in evaluating biogas energy generation opportunities, MnTAP can facilitate:
    • A no-cost screening evaluation with the US DOE Midwest CHP Technical Assistance Partnership (CHP TAP)*. The screening will indicate if electrical power generation and thermal recovery (i.e. combined heat and power) from biogas appears promising, or under what future conditions it might become promising.
    • Follow on technical assistance, including engineering evaluation and/or feasibility study, through the US DOE Midwest CHP TAP to confirm cost effectiveness for promising CHP situations, and to characterize an appropriate biogas and CHP configuration.
  4. *The Midwest CHP Technical Assistance Partnership is a DOE supported regional center promoting and assisting in developing the market for Combined Heat and Power (CHP) technologies.

    WWTP image
  5. Information on State and Federal Financial Assistance – As appropriate to needs, MnTAP will facilitate connections to additional providers of financial assistance ranging from utility incentives to low-interest loans, to state vetted, energy performance contracts.
  6. MnTAP intern – MnTAP can provide interns to work on an energy conservation project of importance to 3 plants. Upper class, undergraduate students do feasibility analysis to help you select and justify the best options for process improvement, and with your approval can begin the process of implementing change.

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To Participate, Contact MnTAP Today!

To learn more about this project and how your facility can participate, contact AJ Van den Berghe, MnTAP Engineer and Certified Energy Manager, at 612-624-4653 or You can also complete our contact form and we’ll call you at your convenience.

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Who Should Participate

Is your facility:           

  • making capital improvements - are you expanding or redesigning portions of your plant?
  • willing to consider cost-effective changes to reduce total cost of plant operation?
  • using anaerobic digestion or considering changing to anaerobic digestion?
  • exploring the potential of utilizing biogas via combined heat and power (CHP) to generate electricity and offset natural gas purchases?
  • willing to host a MnTAP site assessment or a summer intern to evaluate efficiency opportunities on energy-intensive processing equipment, procedures and operating schedules?

If your facility is planning or considering any of the above, MnTAP can help.

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Additional project Information

The first stage of the project will begin with outreach to a targeted group in September 2015. Additional opportunities for new facilities to participate will be available in 2016 and in 2017.

Anticipated project outcomes for the three-year project include:

  • Engaging WWTP across Minnesota
  • Training 50 operators on Energy Efficiency (E2) and onsite power generation
  • Conducting 10 E2 assessments at sites that are more complex than simple lagoon systems
  • Identifying a conservation opportunity of 2–5 million kWh per year
  • Holding 10 regional discussions on WWTP E2 implementation planning
  • Evaluating 5 combined heat and power (CHP) screenings
  • Completing 1–2 detailed CHP assessments
  • Engaging in 1–2 regional stakeholder discussions on CHP implementation opportunities. 

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U.S. Department of Energy Wastewater Infrastructure Accelerator

The Minnesota Department ghbvbof Commerce is a Partner in the U.S. Department of Energy’s (U.S. DOE) Wastewater Infrastructure Accelerator. The U.S. DOE Wastewater Infrastructure Accelerator is a separate initiative than Wastewater Treatment Plant Project: Energy Efficiency and Renewable Energy Generation outlined above. Do not contact MnTAP for more information, contact Lindsay Wimmer with the Minnesota Department of Commerce at or 651-539- 1771.

According to the U.S. DOE, “The Wastewater Infrastructure Accelerator will work over three years with state, regional, and local agencies that are engaging with water resource recovery facilities in their jurisdiction to accelerate a pathway toward a sustainable infrastructure of the future. The Accelerator aims to catalyze the adoption of innovative and best-practice approaches in data management, technologies, and financing for infrastructure improvement. Partners will seek to improve the energy efficiency of their participating water resource recovery facilities by at least 30 percent and integrate at least one resource recovery measure.”

Learn more about the benefits from the Wastewater Infrastructure Accelerator Factsheet.

Contact: Lindsay Wimmer with the Minnesota Department of Commerce at or 651-539- 1771 to learn more or to sign-up.

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Related Webinars and Events

December 8th, 2015 GreenStep Cities Workshop Webinar

Project Overview: Energy Efficiency and Renewable Energy Opportunities at Minnesota Wastewater Treatment Plants

Webinar Recording

January 13th, 2016 GreenStep Cities Workshop Follow-Up Session

Financing Energy Efficiency and Renewable Energy at Wastewater Treatment Plants

Webinar Recording | Summary of Finance Mechanisms [PDF]


March 24th, 2016

Wastewater Treatment Energy Efficiency Training
Operating efficiently–energy conservation for small to medium wastewater treatment facilities

Course Instructor: Tom Jenkins, PE - JenTech Inc.

Training Recording - Coming Soon
Training Slides [PDF]

Training Topics:
• Electric Costs, Baselines, and Benchmarks
• Energy Conservation Opportunities
• Aeration System Opportunities
• Pumping System Opportunities
• VFDs and Controls
• Payback, Financing Options
• Measurement & Verification



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Success Stories and Resources

MnTAP assessed 10 sites in a previous project and has had a number of intern projects related to wastewater plant energy conservation. We found opportunities to reduce energy use by 5–30%.

#141 | 07/2008

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