Over the last two decades MWRA has embraced the state’s ambitious climate resiliency challenge through Executive Orders to “Lead by Example” by, increasing its renewable energy portfolio to meet 20% or $8 million of its own energy needs, decreasing its greenhouse gas emissions (GHG) by 41%, and incorporating sea-level rise into its facility asset protection program. The Authority has incorporated a future facing pursuit of carbon neutrality and climate resiliency into its core mission to protect public health and provide clean water.
Today, energy efficiency, renewable energy production and preparation for sea-level rise are woven into the DNA of the MWRA.
Yet given the nature of MWRA’s services, specifically wastewater treatment, the path to net-zero or carbon neutrality presents a daunting challenge. Wastewater treatment requires a lot of energy, its processes emit significant amounts of greenhouse gases and regulations require treatment plants to have a backup power source sufficient enough to provide uninterrupted operation. For Deer Island, backup power is supplied by two 26 megawatt diesel powered combustion turbine generators (CTG) which are turned on in advance of every significant precipitation event.
At MWRA wastewater operations represent 90% of all emissions.
“Will MWRA meet the state’s goal of net-zero by 2050?”
This thoughtful question was raised by MWRA Board Member, Brian Swett and in response, MWRA staff prepared a series of three informational briefings.
At the July 2025 Board of Directors meeting, MWRA Manager, Energy, Kristen Patneaude provided the second of three scheduled updates on the Authority’s work on sustainability and climate resiliency. Ms. Patneaude’s presentation focused on the Authority’s success to date managing both energy consumption and production as well as on its ongoing strategy to increase energy efficiency and de-carbonization.
This energy update followed a presentation in April prepared by Michael O’Keefe, Senior Program Manager, Planning, which focused on the MWRA’s progress in reducing greenhouse gas emissions (GHG), and will conclude with a presentation this fall on the Authority’s achievements in protecting vulnerable facilities from the effects of climate change.
As an environmental organization, MWRA has a long-standing commitment to pursuing energy conservation, energy efficiency and utilizing renewable non-carbon energy sources. Grid-tied hydropower facilities, Oakdale and Cosgrove, brought on line in the 1960’s to capture energy where water enters and leaves the reservoirs and moves eastward and downhill into metropolitan area, and are still in operation today. The existing combined heat power system (CHP) utilizing digester gas was put in service in 1997 when the new Deer Island Treatment Plant came online.
Over the last two decades the Authority has embraced the state’s challenge through Executive Orders to “Lead by Example”, increasing its renewable energy portfolio to meet 20% or $8 million of its own energy needs, decreasing its greenhouse gas emissions (GHG) by 41%, and incorporating sea-level rise into its facility asset protection program. Authority has incorporated a future facing pursuit of carbon neutrality and climate resiliency into its core mission to protect public health and provide clean water. Energy efficiency, renewable energy production and preparation for sea-level rise are now woven into the DNA of the MWRA.
At July’s meeting, Secretary Rebecca Tepper, chair of the MWRA Board of Directors expressed her appreciation of the work that has gone into thinking about this challenge at MWRA on so many different levels, noting that the Authority’s approach could be a model for other agencies and companies on how to take a comprehensive approach toward addressing the challenge of climate resiliency.
The MWRA Strategies for GHG emissions:
Energy Efficiency
Renewable Energy
Electrification
Embed carbon reduction into all operations & projects
Energy Efficiency
“The cheapest kilowatt-hour is the kilowatt-hour we don’t use therefore increasing efficiency continues to be our most cost-effective strategy.” – Kristen Patneaude
It is also the MWRA’s most effective strategy for reducing Greenhouse Gas emissions. Through the support of state grants and utility programs, the Authority has performed 60 energy audits and implemented efficiency measures which save over 25 million kilowatt hours of energy on an annual basis.
Renewable Energy
MWRA has sought opportunities to minimize its environmental footprint while maximizing value for ratepayers for decades. Its current portfolio of renewable energy assets include five hydroelectric facilities, two wind turbines, five photovoltaic solar arrays and the Deer Island steam turbines. Together these non-carbon energy sources generate 57,000 megawatts of energy that is either used on-site or sold to the grid.
In 2024 MWRA received a $20 million grant award from the MassDEP Climate Mitigation Trust. The bulk of this award will be utilized for additional renewable energy infrastructure such as canopy and rooftop solar arrays at Deer Island, a ground mounted solar array at Norumbega Covered Storage and the replacement of the damaged wind turbine at Deer Island. The Authority will also use this grant to get reimbursement for a number of building electrification projects, converting fossil-fueled heating systems with efficient electric heat pump systems.
It merits noting that DITP combined heat and power (CHP) system alone makes up 51% of the Authority’s renewable power generation, while also providing the thermal energy equivalent of over five million gallons of fuel oil each year. Replacement of the Deer Island CHP is currently in the design stage with an estimated date of substantial completion of approximately 2033. The new CHP is designed to utilize a more efficient energy conversion process, significantly increase the amount of energy produced by the plant’s digester gas and lower MWRA’s GHG emissions to meet the state’s 2030 climate goals, a few years shy of that deadline.
Electrification
As the region’s electrical grid gets “greener” through system-wide investments in renewable energy sources, electrification of facilities and vehicles is becoming a meaningful approach to reducing greenhouse gas emissions and energy cost savings.
Some of MWRA’s facilities and vehicle fleet present particular electrification challenges. Regulatory requirements for 100% fresh air in wastewater treatment process buildings and specialized heavy-duty vehicles pose present day challenges to full scale electrification. Where it makes sense, the Authority is converting heating and cooling systems to electric heat pump systems and testing their efficacy at smaller facilities.
Decarbonization Standard Procedures
MWRA now requires that every project consider opportunities for de-carbonization. New building designs are required to review rooftop solar feasibility and ensure future solar readiness and also conduct a social coat of carbon sensitivity analysis
Massachusetts (and MWRA) – national leaders
Massachusetts has long been a national leader in climate policy, combining ambitious emissions targets with innovative resilience planning. The state is positioned to become a global climate-tech innovation hub.
When Governor Deval Patrick signed EO 484 “Leading by Example – Clean Energy and Efficient Buildings” in 2007, then MWRA Chair and first Secretary of the Massachusetts Executive Office of Energy and Environmental Affairs, Ian Bowles encouraged MWRA sign on to meet the challenge, despite the lack of a legal imperative for MWRA to do so.
Today, MWRA is enjoying real fiscal benefits from its early commitment to “do the right (environmental) thing“. By leveraging grants, rebates and other incentives to improve project economics and reduce budget impacts of investments in energy efficiency, renewable energy and decarbonization the Authority has developed its own renewable energy infrastructure and reduced its energy consumption.
The path to net-zero
In 2023 MWRA was honored with the ‘Leading By Example’ award from the Massachusetts Department of Energy Resources for its long-standing leadership in environmental stewardship and dedication to advancing Massachusetts’ climate and energy goals.
With the help of grants and incentives, MWRA invested early in energy efficiency measures and emerging renewable energy technologies. Technologies like solar energy and electric heat pumps are now proven and economically viable climate change mitigation measures that make smart long-term business sense. And the organization now has the experience and expertise to explore and trial innovative technologies & new applications of existing technologies in pursuit of future emission reductions and cost-savings.
The path to the state’s goal of net-zero by 2050 is not straight forward and relies heavily on continued electrical grid emission reductions. Yet MWRA remains committed to leaving no stone unturned. As example, MWRA is currently piloting battery storage at its Brattle Court pump station and Chelsea Administration building, and also conducting a large-scale battery energy storage analysis for Deer Island. If feasible, battery storage might be able to reduce the use of the Deer Island diesel powered CTG system during storm events, tackling one of the elephants in MWRA’s emissions room.
New England states and Massachusetts in particular have been and will continue to be national leaders in addressing climate change. MWRA is playing a vital role in this work by developing and testing innovative solutions, delivering near-term emission reductions and laying the groundwork for broader action through its leadership.
Ultimately national and international efforts are necessary to slow the speed and severity of impacts climate change. Real progress is being made as more businesses and individuals making decisions like MWRA using a “triple bottom line” framework that includes people and the planet.
This fall the Board will learn about how MWRA is assessing and addressing the direct costs of climate change; facility vulnerability to extreme weather and sea-level rise.
We look forward to bringing you insights from this briefing and a broader GHG Reduction Plan being developed in future Board Briefs.
New England states and Massachusetts in particular have been and will continue to be national leaders in addressing climate change. MWRA is playing a vital role in this work by developing and testing innovative solutions, delivering near-term emission reductions and laying the groundwork for broader action through its leadership.
