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As chief operating officer of PJM, Stu Bresler is responsible for Operations, Markets, Planning, Information Technology Services, and Security & Business Continuity.
Prior to serving as COO, Stu oversaw all aspects of PJM’s market functions and corporate strategy. His responsibilities covered all markets operated by PJM, including those for capacity, Day-Ahead and Real-Time energy, ancillary services, Financial Transmission Rights, and Demand Response operations.
Bresler has also been directly involved in the evolution of PJM’s market design, including the integration of demand response and renewable resources, and the development of analytics around the performance of those markets. An employee of PJM since 1994, Bresler also held other leadership and management positions within the Market Services Division, as well as engineering positions in the Operations Division.
Bresler started his career at PJM in 1994 as a professional engineer supporting System Operations, and he was later responsible for implementing PJM’s Demand Response program and, ultimately, market design for the RTO. Bresler was key in the development of mechanisms by which PJM’s operations and markets are coordinated with those of surrounding Balancing Authorities and regional transmission organizations.
Bresler earned a Bachelor of Science in electrical engineering and a Master of Management in business administration from The Pennsylvania State University. He has also been a licensed professional engineer in the state of Pennsylvania and certified by the National Association of Corporate Directors (NACD).
Bresler is chair of the board of APEx (the Association of Power Exchanges), an international organization of electricity and gas market operators, and president of GO15, the worldwide organization of very large power grid operators. He has been a long-time volunteer for Habitat for Humanity of Chester County and is currently serving on the organization’s board of directors for the second time. Bresler also previously served on the external advisory board for the Department of Energy and Mineral Engineering in the Penn State College of Earth and Mineral Sciences.
Ben Byboth is the Director of business development and strategy at Commonwealth Fusion Systems (CFS). CFS is the leading, largest private company designing and building fusion power plants. Ben's team focuses on all activities related to the commercialization of fusion energy including siting, project development, and customer engagement.
Before joining CFS, Byboth held pivotal roles at major electric utilities. Most recently, as the Director of Grid Modernization at Eversource Energy, he focused on regulatory work toward a more reliable and sustainable power grid. Before that, Byboth was an innovation leader at Entergy's KeyString Labs and led the development of multiple new lines of business. His more than 16 years experience in nuclear power plant operations, maintenance, engineering, and leadership includes eight years with the US Navy on submarines and eight years with commercial power plants.
Ben holds a bachelor of science in nuclear engineering technologies from Thomas Edison State University, studied chemical engineering at the University of New Hampshire, and obtained a master of business administration from the Tulane Freeman School of Business.
Raised in central Virginia, Cosby attended the United States Naval Academy in Annapolis, Maryland, earning a mechanical engineering degree. Subsequently, he attended flight school in Pensacola, Florida and earned his Naval Aviator wings, achieving a childhood dream to serve our Nation as a pilot in the United States Navy. During his time in the Navy, Cosby was stationed in Texas, Maine and Florida and deployed throughout Western Europe, South America, Iceland and Puerto Rico while flying the P-3 Orion.
After 10 years of active military service, Cosby transitioned to the electric utilities industry, serving in roles at Dominion Energy, Alstom, General Electric and eventually joining Old Dominion Electric Cooperative (ODEC) in 2018. Cosby assumed the duties of ODEC President and CEO in February 2025, responsible for all facets of the Generation and Transmission Cooperative’s mission of providing affordable, reliable and responsible electricity for ODEC’s members. Previously at ODEC, he filled the roles of Director of Asset Management, Vice President of Regulatory Affairs and Chief Operating Officer. ODEC reported 2025 operating revenues of $1.3 billion and assets totaling $2.4 billion.
In addition to his duties serving as President and CEO of Old Dominion Electric Cooperative, Cosby also serves on the Board of Directors for both the Alliance for Cooperative Energy Services (ACES) and for the National Renewables Cooperative Organization (NRCO).
Cosby is married; the father of two sons and a daughter and enjoys spending time with his family hiking, boating, or taking weekend trips in Virginia.
As part of the ACES Senior Management team, Matthew Fischesser is responsible for leading the IT organization at ACES. Prior to becoming CIO, Matthew held a variety of positions over his tenure at ACES, in both Process Control and IT. Prior to joining the ACES team, Mr. Fischesser was a Senior Consultant at Deloitte & Touche LLP.
In leading the ACES IT organization, Matthew and his team are responsible for implementation and around-the-clock support of ACES’ generation operations, trading, risk, analytical, and settlement software solutions; maintaining, enhancing, and supporting a robust and reliable telecommunications and network infrastructure; designing and implementing best practice controls to meet regulatory and financial reporting requirements; developing and managing physical and cyber security programs; and leading business continuity and disaster recovery planning and readiness for ACES’ four regional trading centers and the national service center.
Matthew has experience leading large-scale system implementations, managing vendor relationships, building key technology partnerships, directing enterprise architecture design, managing ACES Member and Customer integration and consulting efforts, and supporting the planning and establishment of ACES’ technical vision. He has successfully led numerous strategic, multi-million dollar implementations including SAP enterprise resource planning system integration projects, EMS/GMS/SCADA solutions, customer relationship management solutions, commodity trading and risk management systems, and ISO bid to bill solutions.
Matthew has a proven record of operational excellence, financial stewardship, customer service, leadership, and innovation. He has an extensive knowledge of various energy markets and the services ACES provides to its Members and Customers, including forecasting, portfolio optimization, market operations, generation operations, risk management, settlements, energy allocation, and invoicing.
Matthew holds a Bachelor’s degree from Indiana University (IU) and an MBA from IU’s Kelly School of Business. He is a Certified Information Technology Professional (CITP), Certified Information Systems Auditor (CISA), as well as an inactive Certified Public Accountant.
Kendra Graves is Vice President of Portfolio Strategy and Planning at Central Iowa Power Cooperative, a G&T in Cedar Rapids, Iowa. In this role, Kendra is responsible for power supply planning and leads the organization through an ongoing power supply transition. To date, this has included the successful negotiation of a nuclear and many wind and solar power purchase agreements. Kendra’s group prepares power supply cost projections and evaluates the impacts of resource adequacy in MISO’s changing market. In addition, Kendra and her team develop long-term load forecasts and support member distribution cooperatives with new load contracts, rate design and power bill projections.
Kendra, as part of the CIPCO leadership team, supports CIPCO’s planning goals, risk management and strategic decisions which included collaboration with member cooperatives to develop a new wholesale power contract. Kendra serves on the National Renewables Cooperative Organization board. She holds a Bachelor of Science degree in mathematics and physics from South Dakota State University.
Don Gulley joined Big Rivers as President and Chief Executive Officer in January 2024. Gulley has over 35 years of diverse utility management experience working for regulated & merchant investor-owned utilities (IOUs) and G&T cooperatives.
He most recently served as President and CEO for ten years at Southern Illinois Power Cooperative (SIPC), a generation and transmission (G&T) cooperative based in Marion, Illinois. SIPC is owned by seven Member-Owner distribution cooperatives with $700 million in assets and a generation portfolio consisting of coal, gas, hydro, and renewables. Before joining SIPC, Gulley served as Vice President of Regulatory and Market Affairs for Sunflower Electric, a G&T cooperative located in western Kansas. Gulley began his career with Ameren, formerly Union Electric, in 1988, where he worked in various leadership capacities for both the regulated and merchant business units.
Gulley currently sits on several industry boards. Gulley has served as Chairman of the Board for both ACES, a national energy management organization, and the National Renewables Cooperative Organization (NRCO). He was also the North American Electric Reliability Corporation (NERC) Member Representative for the National G&T Managers Association.
Gulley holds an MBA from Southern Illinois University – Edwardsville and bachelor’s degrees in electrical engineering and geology from Southern Illinois University – Carbondale.
Andrew Hall is Senior Vice President and Chief Strategy Officer at ACES in Carmel, Indiana. In this role, Andrew oversees ACES’ Portfolio Strategy, Portfolio Modeling, Transmission, Resource Planning, Data Science and Origination teams. Andrew joined ACES in January 2005 and has since gained a broad range of skills through ACES’ Portfolio Modeling, Transmission, and Portfolio Strategy departments.
Andrew was previously Vice President of Portfolio Strategy where he focused his efforts on managing the long-term portfolio and risk management strategies for several ACES’ Members and Customers, including managing mid-to-long term strategic planning objectives for traditional and structured portfolios. This process includes asset management, asset valuation, integrated resource planning, regulatory impacts on portfolios and markets, commodity market risk management, capacity management, and transmission markets. In this role Andrew also oversaw ACES’ Fuels, Meteorology and Transmission functions. In addition to the Strategy role, Andrew also served as Interim Vice President of Planning and Power Supply for one of ACES’ Members, Central Electric Power Cooperative, Inc., helping fill a need until a permanent solution was established.
Andrew has spent his entire career at ACES. Prior to joining Portfolio Strategy, Andrew spent 11 years in ACES’ Transmission Department in various capacities, culminating with the role of Executive Director of Transmission Services. During this time, Andrew was responsible for congestion management strategies across PJM, MISO, SPP, ERCOT, and CAISO ranging from one month to ten years, long-term physical transmission management, the completion of a wide array of consulting project in all regions of the United States, and the growth and development of the transmission staff.
Andrew has a BA from Vanderbilt University and an MBA from Purdue University. He is also Series 3 certified with the National Futures Association.
Buddy was born and raised in Iowa. He enlisted in the United States Navy in 1986 as a submarine reactor operator and was selected for the Navy’s Nuclear Enlisted Commissioning Program (NECP). He attended Auburn University and completed his Bachelor of Science degree in electrical engineering. Buddy was assigned to nuclear submarines and shore assignments over a 20-year career. His final naval assignment was at Naval Reactors in Washington, D.C.
Buddy retired from the Navy in 2007 and returned to Iowa, where he served as the regional director of generation for Iowa-based power plants at Alliant Energy.
Buddy then joined Associated Electric Cooperative, Inc. of Springfield, Missouri, in 2011 and served as vice president of engineering and construction until coming to Arkansas.
Buddy became the President and CEO of Arkansas Electric Cooperative Corporation and Arkansas Electric Cooperatives, Inc. in October 2019. Hobbies are Reliability, Affordability, and Responsibility. Buddy and Tracy have been married for 37 years and have three children (Nick, Chad, and Madeline) and five grandchildren (Logan, Lola, Luna, Owen, and Malia) who are the reason for it all.
Kari Hollandsworth is a seasoned executive with over 25 years of experience in the utility industry, distinguished by her expertise in strategic leadership, market operations, and risk management. Kari’s leadership is grounded in the cooperative principles of collaboration and fiscal responsibility. Since joining Golden Spread in 2009, Kari has held pivotal roles spanning resource planning, including the integration of grid-switchable generation, electric trading, finance, forecasting, and risk oversight. As President & CEO since 2020, she has led the cooperative through a period of innovation and growth, including the emergence of mega consumers, whose significant demand is reshaping market dynamics and driving new strategies for sustainable value for member-owners.
Kari’s board service includes the Oklahoma Association of Electric Cooperatives, ACES, and the National Renewables Cooperative Organization, and Women in Science Endeavors Program.
Prior to Golden Spread, Kari spent 11 years at Xcel Energy, further developing her expertise in utility finance and operations. She holds a bachelor’s degree in Economics and Business Management from Cornell University in Ithaca, New York.
Corey is the Sr. Vice President and Chief Operations Officer – Power Supply and Generation for Sunflower Electric Power Corporation. His current responsibilities include generation operations, generation maintenance, generation engineering, generation environmental compliance, system operations, market operations, power contracts, resource planning, and billing. Corey has been with Sunflower for 33 years, beginning his career with the company as a generation engineering intern. Corey holds a bachelor’s degree in mechanical engineering from Kansas State University, and he is a licensed professional engineer in the state of Kansas.
Jessica Matlock is President and CEO of PNGC Power, a generation and transmission cooperative that provides wholesale power and strategic services to 25 rural electric cooperatives across seven Western states. She leads PNGC’s efforts to secure reliable, cost-effective energy for rural communities while advancing new generation development and long-term power supply strategies across the Pacific Northwest.
Prior to joining PNGC, Matlock served as CEO of La Plata Electric Association in Colorado, where she was the first female CEO in the cooperative’s 85-year history and strengthened the utility’s financial position while launching innovative energy programs. Earlier in her career, she held leadership roles at Snohomish County PUD, served as an energy policy advisor in the U.S. Senate, and worked at the Bonneville Power Administration. Matlock is a U.S. Coast Guard veteran and holds degrees from the University of Washington and Portland State University.
Matt Moore joined Wabash Valley Power Alliance in September 2020 and serves as Executive Vice President of Power Supply. In this role, he leads the development and execution of Wabash’s power supply strategy, including portfolio planning, risk management, wholesale market operations, and purchased power agreements to support the long-term needs of member cooperatives.
Matt earned an Industrial Technology degree from Purdue University and an MBA from Indiana State University. Prior to joining Wabash, Matt held leadership positions at ACES, including Vice President of Regulatory and Reliability Services and Executive Director of Portfolio Strategy. In these roles, he led the development and implementation of hedging strategies tailored to each member’s unique risk tolerance and market position. Earlier in his career, Matt was an Hourly Trader when ACES first was getting started, gaining operational expertise in energy markets. He also worked directly with Wabash on its legacy demand response program, providing him with early insight into the cooperative’s membership and operations.
In the past two years, Matt and his team have advanced Wabash’s strategic position through the acquisition of the St. Joseph Energy Center, a combined cycle facility in northern Indiana, and by developing a strategy to secure an agreement with Meta, the largest load in Wabash’s history. These efforts reflect his focus on disciplined growth, market alignment, and long-term value for members.
A lifelong Hoosier, Matt is proud to add “Dance Dad” to his many titles. He and his wife, Crista, have three daughters and enjoy supporting their competitive dance activities. Matt is also active in CrossFit and enjoys golfing when time and weather allow.
Don Mosier serves as President and Chief Executive Officer of East Kentucky Power Cooperative, Inc., a not-for-profit generation and transmission cooperative owned by 16 electric distribution cooperatives across 89 Kentucky counties. EKPC provides safety, reliable, and competitive electric service to more than one million customers.
With more than three decades of experience in the electric cooperative and utility industry, he has led organizations through significant industry transformation while maintaining a strong commitment to safety, system reliability, and fiscal discipline.
Prior to his current role, he served as EKPC’s Executive Vice President and COO since 2010. Prior to EKPC, he was a Vice President of Ameren Corporation, an investor-owned utility serving wholesale customers throughout the Midwest.
Mr. Mosier brings deep expertise across the transmission and generation value chain, including engineering, fossil and nuclear plant construction, operations, energy trading, and manufacturing. His leadership experience spans both cooperative and investor-owned utility environments, providing a well-rounded perspective on today’s evolving energy landscape.
He holds a bachelor’s degree in Civil Engineering from the University of Virginia and a Master of Business Administration from the Kenan-Flagler Business School at the University of North Carolina. He is a registered professional engineer.
Mike Nasi is a partner with Jackson Walker LLP where he practices environmental and natural resources law. Mike attended the University of New Mexico, the University of Texas (BA 1991), the University of Texas School of Law, and the University of Houston Law School (JD 1994). For over three decades, Mr. Nasi has appeared before state and federal regulatory agencies and appellate courts working on natural resource infrastructure project development issues. His clients have ranged from small governmental bodies to state governments; multi-state compacts to state and national industry associations; and small, privately-held companies to multi-national public corporations.
Mr. Nasi’s docket is focused primarily on compliance counseling associated with thermal power plants, including significant co-development projects involving new and existing power generation and large digital infrastructure loads. Mike is also currently counsel for state, energy and infrastructure interests in regional and national policy initiatives and several legal proceedings pending before state and federal agencies and multiple Federal Circuit Courts of Appeals and the Supreme Court of the United States.
ELECTRIC POWER-SPECIFIC EXPERIENCE:
Mike’s entire legal career has involved electric generation issues. In addition to managing an extensive regulatory practice, Mike helps coordinate multi-state outreach efforts regarding regulatory policies and market rules impacting electric power.
Mike has been relied upon an expert witness and speaker at docketed hearings, legislative proceedings, energy policy events, and classrooms across the country, including invited briefings at the White House and the United Nations, and is published in several trade, law, and business journals on environmental and energy law. Mr. Nasi participates on advisory boards or as counsel for state governments, universities, and interstate compacts and governmental organization across the country, including:
GENERAL ENVIRONMENTAL & INFRASTRUCTURE LEGAL EXPERIENCE:
For his entire career, representing infrastructure entities ranging from the aforementioned power sector to the digital infrastructure, mining, steel, recycling, petrochemical, composting, and public works sectors, his practice has spanned across numerous federal and related state environmental, natural resource and utility regulatory programs including:
Mike is a past Chairman of the State Bar of Texas Environmental and Natural Resources Law Section and served on the adjunct faculty for Rice University’s “Leadership & Decision Making in the Energy Industry” course and as a guest lecturer in the “Energy Law & Policy” course at the University of Texas Law School. Most recently, Mr. Nasi has assisted in an adjunct role in the University of Houston Center for Carbon Management in Energy (CCME), including as faculty for the Symposium entitled “Managing CCUS: Risks and Financing,” UH Energy 2022-2023 Critical Issues in Energy Symposium Series (December 2022).
RECOGNITIONS:
CIVIC INVOLVEMENT:
Life:Powered – Senior Advisor
Mike Steffes assumed his role as President & Chief Executive Officer of ACES in September of 2013. As Senior Vice President & Chief Operating Officer at ACES for the previous 14 years, Mike has been responsible for all commercial activities of the company. This encompasses managing the company’s areas of Marketing, Origination, Trading, Structuring, Fuels, and Emissions. Mike offers customers a unique level of management experience in energy trading, having held similar executive positions with Pennsylvania Power & Light, Valero Energy and Hadson Gas Systems.
During 2010, Mike was interim chief operating officer at East Kentucky Power Cooperative (EKPC) in Winchester, KY, heading up Production, Transmission, Operations and Planning activities. On assignment from ACES Mike was a significant contributor to the successful transition of EKPC during a challenging financial period.
As Vice President of Marketing and Trading for PP&L in Allentown, Pennsylvania, Mike led the development of the utility’s unregulated trading subsidiary into a profitable, full-service trading organization.
At Valero Energy, Mike helped to pioneer state of the art risk management systems that provided portfolio valuation and calculated value at risk, which helped maximize profitability and managed the risk of Valero’s energy business.
At Hadson Gas, Mike led one of the country’s leading natural gas marketing and trading businesses with a large physical and financial presence in the West Coast, Mid-continent, East Coast and Gulf Coast Regions.
In addition to his many years of hands-on energy trading experience, Mike holds a Master of Business Administration degree from the University of Detroit.
Kevin Suhanic is Vice President of Portfolio Strategy and Origination at ACES in Carmel, Indiana. In his strategy role, he is responsible for managing risk and optimizing outcomes for ACES’ Members’ and Customers’ long-term portfolios. These efforts include asset valuation, assessment of regulatory impacts, and assessment of commodity and transmission markets. Kevin conducts financial analyses for acquisitions/divestitures and has served as an expert witness in litigation support.
Kevin also oversees ACES’ Origination group, which provides ACES’ Members and Customers with commercial wholesale electricity, renewable energy credits, and emissions market opportunities that support long-term risk mitigations. Kevin directs these efforts to proactively identify, negotiate, and coordinate the valuation and execution of structured products for these market products on behalf of ACES’ Members’ and Customers’. He is responsible for ACES’ request for proposals (RFP) process and negotiation of power purchase agreements and other power supply agreements.
Kevin joined ACES in February 2007 as a Financial Transmission Rights Modeler and led ACES’ Transmission group for several years as Director of Transmission Services. In this role, Kevin oversaw congestion management and consulting activities, including power flow modeling for the Eastern Interconnect, WECC, and ERCOT and trading in the congestion markets.
Kevin monitors and advises Members and Customers on market developments and regulatory changes. He has extensive experience in financial modeling and accounting. He has also been involved in several implementations for Members and Customers transitioning into nodal markets and has served on various cross-functional teams focused on new regulations and new markets.
Prior to joining ACES, Kevin began his career at PriceWaterhouseCoopers, LLC as an associate in the Audit and Assurance division, with a tour in the International Taxation division. This included providing accounting treatment advice and implementing specific tax strategies.
Kevin holds a Bachelor’s of Science and a Master’s in Business Administration from the University of Notre Dame. He is Series 3 certified by the National Futures Association. Kevin is also a Certified Public Accountant (inactive) in Ohio.
Andy Whitesitt is Senior Vice President and Chief Commercial Officer at ACES in Carmel, Indiana. In this role, Andy leads ACES’ Business Development, Fuels, Meteorology, and West Trading teams. Andy joined ACES in July 2003 and has held various positions in power, natural gas, and business development, most recently as Senior Vice President and Chief Business Development Officer.
Andy began his energy career in 2001 with ICAP Energy as a Commodity Broker. In addition to providing leadership to fuels and power trading, Andy has presented on a variety of topics including natural gas and power markets, as well as the ever-evolving electric utility industry.
Andy holds an MBA and a MS in Finance from Indiana University’s Kelley School of Business.
Kevin Zemanek is Vice President of Operations at Buckeye Power, Inc., with responsibility for resource planning, market operations, information technology, enterprise risk management, field engineering, and RTO regulatory activities. He serves on the NRCO Board and joined Buckeye Power in 2004. Kevin holds a Bachelor of Science in Computer Engineering Technology and a Master of Science in Engineering Management from the University of Dayton.
