On this page:
- Overview of Energy Efficiency
- Determining Energy Usage
- Cutting Energy Usage and Costs
- Renewable Energy Options
Overview
For many municipal governments, drinking water and wastewater plants typically are the largest energy consumers, often accounting for 30 to 40 percent of total energy consumed. Overall, drinking water and wastewater systems account for approximately 2 percent of energy use in the UnitedStates, adding over 45 million tons of greenhouse gases annually.
As much as 40 percent of operating costs for drinking water systems can be for energy.
By incorporating energy efficiency practices into their water and wastewater plants, municipalities and utilities can save 15 to 30 percent, saving thousands of dollars with payback periods of only a few months to a few years.
EPA Webinars on Energy Efficiency for Water and Wastewater Utilities
- Energy Self‐Assessment Tools and Energy Audits for Water and Wastewater Utilities
- Innovative Energy Conservation Measures at Wastewater Treatment Facilities
- Solar Energy for Water and Wastewater Utilities – Step-by-Step Project Implementation and Funding Approaches
Determining Energy Usage
As a utility manager, understanding how your water or wastewater utility uses energy and how your electricity provider structures rates will help you better manage both costs and your facility’s operations. The first step is to determine your facility’s baseline energy use. Another important step is to understand what impact energy-intensive processes such as pumping and aeration have for your facility and how you can prioritize improvements.
You can determine baseline energy use using third-party energy audits or self-assessments. Both water utility professionals and technical assistance providers can benefit from the resources provided below.
Tools and Guidance for Water Industry Professionals
- EPA's Energy Use Assessment Tool: An Excel-based tool that small- to medium-sized systems can use to conduct a utility bill and equipment analysis to assess individual baseline energy use and costs.
- Energy Use Assessment Tool for Excel 2003 (xls) (4 MB)
- Energy Use Assessment Tool with Example Data for Excel 2003 (xls) (4 MB)
- Energy Use Assessment Tool for Excel 2010 (xlsm) (3.6 MB)
- Energy Use Assessment Tool with Example Data for Excel 2010 (xlsm) (3.7 MB)
- Energy Use Assessment Tool User's Guide
- Energy Use Assessments at Water and Wastewater Systems Guide
- Benchmarking Your Energy Performance with Portfolio Manager- The ENERGY STAR™ programincludes wastewater and drinking water treatment in its Portfolio Manager. This interactive energy management tool is used to track and assess energy and water consumption. The tool can help a utility set targets for investment priorities, verify efficiency improvements, and calculate its carbon footprint.
Paying for Energy Efficiency Audits
- U.S. Department of Energy's Save Energy Now Program-This is an initiative to reduce industrial energy intensity. Companies can participate in no-cost energy assessments.
- U.S. Department of Agriculture, Rural Development Renewable Energy for America Grant Program-Provides grants for energy audits and renewable energy development assistance.
- Rural Assistance Center-Offers funding to help rural communities, including funds for energy audits and renewable energy.
- EPA's Clean Water and Drinking Water State Revolving Funds (SRF) areimportant sources of financing for wastewater and drinking water infrastructure. SRF funds can be used to conduct energy audits.
- Clean Water State Revolving Fund
- Drinking Water State Revolving Fund
Cutting Energy Usage and Costs
Energy Management
Energy costs often make up 25 to 30 percent of a utility's total operation and maintenance (O&M) costs. They also represent the largest controllable cost of providing water and wastewater services. EPA works with utilities to manage and reduce costs, using the steps described in its Energy Management Guidebook for Wastewater and Water Utilities. The Guidebook takes utilities through a series of steps to analyze their current energy usage, use energy audits to identify ways to improve efficiency, and measure the effectiveness of energy projects.
EPA's regional offices are working with over 150 utilities to help develop energy management programs using the Guidebook and develop case studies of benefits seen by utilities.
- EPA's Ensuring a Sustainable Future: An Energy Management Guidebook for Wastewater and Water Utilities (PDF)(113pp, 1.5MB, About PDF)
Best Energy Practices
Once you know your baseline energy use and where you are consuming the most energy, you can identify and prioritize energy conservation opportunities resulting in meaningful cost savings.
- EPA's Energy Efficiency in Water and Wastewater Facilities: A Guide to Developing and Implementing Greenhouse Gas Reduction Programs - The guide provides comprehensive information for local government staff and policy makers on how to design and implement energy management programs for water and wastewater facilities, including new, existing, and renovated buildings, and day-to-day operations.
- A Primer on Energy Efficiency for Municipal Water and Wastewater Utilities (PDF)(72 pp, 1.5 MB, About PDF)-The primer was published by the World Bank’s Energy Sector Management Assistance Program, (ESMAP). Principal ESMAP efforts focus on infrastructure in developing nations, but this report also applies to energy efficiency for small and medium, urban and rural, water and wastewater systems.
- EPA's Evaluation of Energy Conservation Measures for Wastewater Treatment Facilities (PDF)(122 pp, 7.09 MB, About PDF)
- Motor Efficiency, Selection, and Management: A Guidebook for Industrial Efficiency Programs(29pp, 896K, About PDF)-Published by Consortium for Energy Efficiency.
- Reducing Operating Costs and Energy Consumption at Water Utilities - Brochure for water utility managers demonstrating energy-efficient technologies to help reduce energy usage and save money.
- Strategies for Saving Energy at Public Water Systems (PDF) (575.4KB) -Providing safe drinking water is an energy intensive activity. Energy is typically needed for raw water extraction and conveyance, treatment, water storage and distribution. Thisdocument describes strategies for saving energy at public water systems.
- U.S. Department of Energy's Improving Pumping System Performance, A Sourcebook for Industry (PDF)(122pp, 3.2MB, About PDF)
Case Studies
- Increasing Energy Efficiency Through ARRA Funding: New York State Wastewater Initiatives(PDF)(4 pp, 3.11 MB, About PDF) -Highlights many energy-efficient projects funded through New York State’s Clean Water State Revolving Fund Program under the American Recovery and Reinvestment Act Green Project Reserve of 2009.
Training
- The ENERGY STAR program’sPortfolio Manager includes wastewater and drinking water treatment facilities. The Portfolio Manager is an interactive energy management tool that tracks and assesses energy and water consumption. The tool can help a utility set targets for investment priorities, verify efficiency improvements, and calculate its carbon footprint. ENERGY STAR offers free online training to help get you started.
Paying for Energy Efficiency Improvements
- EPA's Clean Water and Drinking Water State Revolving Funds are important sources of financing for wastewater and drinking water infrastructure. Equipment upgrades to improve energy efficiency and reduce energy use are eligible for funding from these programs.
- Clean Water State Revolving Fund
- Drinking Water State Revolving Fund
- Database of State Incentives for Renewables andEfficiency (DSIRE)-A comprehensive source of information on state, local, utility, and federal incentives and policies that promote renewable energy and energy efficiency. Established in 1995, DSIRE is an ongoing project of the North Carolina Solar Center and the Interstate Renewable Energy Council, funded by the U.S. Department of Energy.
State Efforts to Promote Energy Efficiency
States are developing programs to help public water systems and wastewater treatment facilities better manage their energy use. Examples include:
- Massachusetts: Energy Management Pilot for Wastewater and Drinking Water Plants
- Wisconsin: Energy Center of Wisconsin
- New York: The New York State Energy Research and Development Authority- Offers financial assistance to municipalities to identify opportunities and install new equipment for energy efficiency upgrades in their water and wastewater treatment facilities. Some projects include energy performance benchmarking, 50:50 cost shares for energy assessments by pre-qualified consultants, and the installation of sub-metering equipment to determine the energy consumption of the various processes within the facility.
Related Resources
- Alliance to Save Energy
- Consortium for Energy Efficiency
- Focus on Energy
- Electric Power Research Institute
Renewable Energy Options
Green power is electricity produced from renewable resources, such as solar, wind, geothermal, biomass, and low-impact hydroelectricity. Buying green power is one of the easiest and most effective ways to improve your organization's environmental performance.
On-site Energy Generation
In addition to consuming energy, wastewater utilities can generate energy. Combined heat and power (CHP), also known as cogeneration, is a reliable, cost-effective option for wastewater treatment facilities that have, or are planning to install, anaerobic digesters. Biogas from anaerobic digesters can be used in a CHP system as "free" fuel to generate reliable electricity and power.
- Combined Heat and Power (CHP) Partnership - Avoluntary program that works to reduce the environmental impact of power generation by promoting the use of CHP. The partnership works closely with energy users, the CHP industry, state and local governments, and other clean energy stakeholders to encourage the development of new projects and promote their environmental and economic benefits.
- EPA's CHP Partnership Report: Opportunities for and Benefits of Combined Heat and Power at Wastewater Treatment Facilities (PDF)(48 pp, 726 K, About PDF)
In addition to CHP, utilities can use various alternative energy sources to reduce their dependence on traditional energy sources. Options include solar panels (the most common), wind turbines, fuel cells, and micro turbines. Utilities can purchase and operate their own renewable energy generation equipment or contract with a third-party provider that owns and manages the green power on-site for them.
- The Customer's Guide to Solar Power Purchase Agreements- This guide assists organizations that want to benefit from fixed-price energy through hosting solar power systems owned and operated by a third party.
Purchasing Green Energy
Instead of generating renewable energy on-site, some utilities opt to purchase renewable energy directly from the power grid or by purchasing renewable energy certificates (RECs). RECs are credits sold separately from electricity. They represent the environmental, social, and other positive attributes of power generated by renewable resources and enable organizations to choose renewable power even if their local utility or power marketer does not offer a green power product. Whether these options are available varies based on your facility's location and your electricity provider's offerings.
- Guide to Purchasing Green Power-The Green Power Partnership is a voluntary program through the EPA that supports organizations by offering expert advice, technical support, tools, and resources to buy green power and reduce the environmental impacts associated with purchased electricity use. Partnering with EPA can help your organization lower the transaction costs of buying green power, reduce its carbon footprint, and communicate its leadership to key stakeholders.
Funding Green Power
- U.S. Department of Agriculture, Rural Development, Rural Energy for America Program (REAP) Guaranteed Loan Program-This program encourages the commercial financing of renewable energy (e.g., bioenergy, geothermal, hydrogen, solar, wind, and hydroelectric power) and energy efficiency projects. Under the program, project developers work with local lenders, who in turn can apply to U.S. Department of Agriculture Rural Development for a loan guarantee of up to 85 percent of the loan amount.
- Database of State Incentives for Renewables and Efficiency (DSIRE)-This database contains information on state, local, utility, and federal incentives and policies that promote the adoption of solar technologies. Funded by the U.S. Department of Energy's Solar Energy Technology Program, DSIRE SOLAR is a new component of the DSIRE project that provides solar-specific policy information to consumers, policy makers, program administrators, the solar industry, and other concerned parties.
State and Local Efforts to Promote Green Energy
State and local governments are developing programs to help public water systems and wastewater treatment facilities use renewable energy.
- The Massachusetts Department of Environmental Protectionis working on several efforts to integrate renewable energy and green building into their state clean water and drinking revolving loan fund programs.
- The Washington Suburban Sanitary Commission is embracing wind power as an energy source to run one-third of its drinking water and wastewater operations. Their action places them as one of the Top 30 Local Government partners in EPA's GreenPower Partnership.
- The City of Santa Barbara's El Estero WWTP is an 11-million-gallons-per-day secondary treatment facility equipped with a 4.3-million-gallons-per-day tertiary treatment for recycled water. The plant uses waste gas fuel cell technology to produce nearly one-half of the facility's electricity needs.
Related Resources
- U.S. Department of Energy, Energy Efficiency and Renewable Energy's Green Power Networkprovides information about green power products available through utility green pricing programs throughout the nation.
- Climate Communities is a national coalition of cities and counties that educates federal policymakers about the essential role of local governments in addressing climatechallenges and promoting a strong local-federal partnership to reduce greenhouse gas emissions.
- EPA's State and Local Climate and Energy Program provides technical assistance, analytical tools, and outreach support to states and local and tribal communities.
