The NYISO Executive Leadership team manages the day-to-day operations of New York’s bulk power system and wholesale electricity markets. They oversee grid reliability, market design and operations, system planning, and compliance functions. Working closely with stakeholders and regulators, the team ensures the integration of new technologies and clean energy resources while maintaining a secure and efficient electric system.

Leadership Team

Richard J. Dewey
President & CEO
Richard J. Dewey
President & CEO

Mr. Dewey joined the NYISO in 2000 and has held several pivotal executive roles in Product and Project Management, Strategic Software Development and Quality Assurance. Previously, he spent several years in IT and Network Services for Husky Injection Molding Systems and Niagara Mohawk Power Corporation. He earned a B.S. in Electrical and Computer Engineering from Clarkson University, a M.S. in Computer Engineering from Syracuse University, and is a graduate of Harvard Business School’s General Management Program.
Emilie Nelson
Executive Vice President & COO
Emilie Nelson
Executive Vice President & COO

Emilie Nelson leads the Grid Reliability and Electricity Market functions for the NYISO. In her role she oversees Market Mitigation & Analysis, Market Operations, Market Structures, Operations, and System & Resource Planning. Ms. Nelson joined the NYISO in 2004 and has held several executive roles within the organization. Prior to joining the NYISO she worked for several years in power generation. She earned a B.S. in Mechanical Engineering from Tufts University, an M.B.A. from Pace University, and is a graduate of Harvard Business School’s Advanced Management Program.
Robert E. Fernandez
EVP, General Counsel & Chief Compliance Officer
Robert E. Fernandez
EVP, General Counsel & Chief Compliance Officer

Mr. Fernandez serves as the NYISO’s Chief Legal and Compliance Officer overseeing the company’s legal, regulatory, and compliance strategy. Mr. Fernandez advises the NYISO’s Board of Directors and Senior Leadership Team on federal, state, and local legal issues affecting the company while monitoring the NYISO’s Corporate Compliance Program. Mr. Fernandez has over 30 years' experience in the energy sector. Prior to joining the NYISO in 2000, Mr. Fernandez served as Vice President and Chief Regulatory Counsel for Sithe Energies, Inc., a NYC-based independent power producer. He also served as Senior Specialist Attorney at Long Island Lighting Company, and was associated with the NYC law firm of Cullen and Dykman. Mr. Fernandez began his legal career as a trial attorney with the Internal Revenue Service. Mr. Fernandez holds a B.A. from Stony Brook University, a J.D. from Brooklyn Law School, and an LL.M. in taxation from New York University School of Law.
Diane L. Egan
Secretary to the Board of Directors
Diane L. Egan
Secretary to the Board of Directors

Diane Egan has been with the NYISO since its inception in 1999 and held key positions at the New York Power Pool that preceded it. She brings 50+ years of energy industry and experience to her role which includes Executive Assistant to the NYISO CEOs and as Secretary to the Board.
Doug Chapman
Senior VP & CIO
Doug Chapman
Senior VP & CIO

Doug Chapman leads the Information Technology group, delivering reliable, innovative products and services to our evolving wholesale electricity markets. Mr. Chapman is also responsible for ensuring system compliance with the NYISO’s federal tariff governance and oversight of communications, facilities and enterprise security. Mr. Chapman joined the NYISO in 2015 and has over three decades of experience in the electric utility industry. He has held key leadership roles with the Mid-Continent Independent Transmission System Operator (MISO), National Grid, and Niagara Mohawk. He earned a M.S. in Computer Engineering from Syracuse University and a B.S. in Electrical Engineering from the University of Buffalo.
Cheryl L. Hussey
Vice President & CFO
Cheryl L. Hussey
Vice President & CFO

Cheryl Hussey leads the NYISO’s accounting and financial reporting functions, budget development and oversight, treasury management, procurement and contract administration, corporate credit management and customer settlements. Ms. Hussey joined the NYISO in 2008 and spent over 10 years before that, in key leadership roles at Albany Medical Center. She is a Certified Public Accountant and earned a B.S. in Accounting from the State University of New York at Geneseo.
Kevin Lanahan
Senior VP, External Affairs & Corporate Communications
Kevin Lanahan
Senior VP, External Affairs & Corporate Communications

Kevin Lanahan has more than twenty-five years experience in the energy industry, working for Con Edison, JPMorgan Chase & Co., and National Grid. He holds B.A. degrees in English and Political Science from the State University of New York at Oneonta and an M.B.A. from Norwich University.
Zachary G. Smith
Senior VP, System and Resource Planning
Zachary G. Smith
Senior VP, System and Resource Planning

Zach Smith is responsible for the oversight and implementation of system planning and strategic initiatives for the New York State Transmission System. These include ensuring a reliable electric grid for the future, identifying economic opportunities for transmission investment beneficial to ratepayers, and implementation of system upgrades to enable public policies. Mr. Smith also oversees the interconnection process through which renewable resources and other new generation technologies reliably connect to the New York State electric grid. Since joining the NYISO in 2004, Mr. Smith has spearheaded numerous renewable integration and transmission planning initiatives through key positions of increasing responsibility, and he actively represents the NYISO on Interregional Coordination Committees. He earned B.S. and M.S. degrees in Electrical Engineering from Michigan Technological University.
Karen G. Gach
Deputy General Counsel
Karen G. Gach
Deputy General Counsel

Ms. Gach oversees the company’s legal department and assists in the development of regulatory and compliance strategy. She advises the company on a wide variety of federal, state, and local legal issues. She served as Senior Attorney at the NYISO from July 2004 to 2010. Prior to that, Ms. Gach was an associate with the law firm of Nixon Peabody LLP, representing clients on energy and utility matters and, previously, an associate in the Washington, DC office of the law firm of Cullen and Dykman. Ms. Gach received her Juris Doctor, cum laude, from Albany Law School of Union University where she was the Editor-in-Chief of the Albany Law Journal of Science and Technology. She received a B.A. from the University of Rochester.
Robb Pike
VP, Market Operations
Robb Pike
VP, Market Operations

Robb Pike is responsible for the NYISO's Installed Capacity Market Operations, Distributed Resources Operations, and Operations Performance and Analysis departments. Over his 20+ years with the NYISO his responsibilities have included managing the evolution of the capacity, energy and congestion rights markets to improve efficiency, and expand market features. He has held an array of roles in engineering, operations, information technology, and project and product management. He earned B.S. and M.S. degrees in Electrical Engineering from Clarkson University and a MBA from Union College.
Aaron Markham
VP, Operations
Aaron Markham
VP, Operations

Aaron Markham leads the Grid Reliability and Operations team responsible for ensuring the bulk power grid and wholesale energy markets reliably and efficiently respond to the needs of New Yorkers, every minute of every day. Mr. Markham has held positions of increasing responsibility since joining the NYISO in 1999. Most recently, he served as Director of Grid Operations, overseeing power system operations, dispatcher training, and regulatory compliance of reliability standards. Mr. Markham successfully led efforts to integrate wind and solar resources into NYISO dispatch programs; and increase real-time visibility into wind and solar output. He earned a B.S. degree in Electrical Engineering Technology from SUNY Polytechnic Institute at Utica-Rome and a Master’s in Business Administration from the College of Saint Rose. He is active with the Northeast Power Coordinating Council (NPCC) and chaired its Task Force of Coordination Operation 2019 - 2020.
Deneen Byrne
VP, Human Resources
Deneen Byrne
VP, Human Resources

Deneen Byrne leads the NYISO’s Human Resources department responsible for development of strategic HR policy and procedure, employee engagement, talent acquisition, compensation, benefits and health and safety programs, training and professional development and performance management. Ms. Byrne joined the NYISO in 2012 and spent over fourteen years before that in key management positions in both the manufacturing and hospitality industries. She earned a degree in Legal Studies from the Sage Colleges of Albany, NY. She is also a Society for Human Resource Management Certified Professional and holds a Professional Human Resources Certification from the HR Certification Institute.
Shaun Johnson
VP, Market Structures
Shaun Johnson
VP, Market Structures

Shaun Johnson is responsible for the Market Design, Product and Project Management, Strategic and Business Planning, Research and Development, and Market Training teams. Mr. Johnson joined the NYISO in 2003. He most recently served as the Director of Market Solutions in which he managed comprehensive reforms to NYISO’s Energy and Capacity markets. He previously held roles including Director of Market Mitigation and Analysis, and Energy Market Design Product Manager and has also led project management teams in the design of software and business requirements to implement market system changes. He holds a Bachelor of Arts in Economics from the State University of New York at Albany.
The Board of Directors provides independent oversight and strategic direction for NYISO. Its responsibilities include ensuring organizational independence, approving major policies and budgets, and safeguarding compliance with reliability and market standards. The Board also collaborates with stakeholders through NYISO’s shared governance process to maintain transparency and fairness in market operations.

Board of Directors

Joseph Oates
Chairman
Joseph Oates
Chairman

A New Yorker, Mr. Oates has more than 35 years of experience in the energy industry. He served various roles of increasing responsibility during his 33 years with Con Edison. Most recently Mr. Oates was Chairman of Con Edison Clean Energy Businesses (CEB), focusing on clean energy infrastructure investments. Under Mr. Oates’ leadership Con Edison’s CEB became the second largest solar energy producer in North America.

Mr. Oates also was Chairman, President and CEO of Con Edison Transmission, a subsidiary targeting federally regulated transmission infrastructure investments. Spanning his distinguished career with Con Edison he also served as Senior Vice President, Shared Services; Vice President, Energy Management; Treasurer; and Vice President, Electric Operations.

Mr. Oates holds Bachelor of Engineering and Master of Engineering degrees from Manhattan College, and a Master of Business Administration in Finance from Fordham University. He served in various other Board of Director roles including as Chairman of the Honeoye Storage Corporation, and Vice Chairman, President and Treasurer of Arts Westchester.

 

 
David R. Hill
Vice Chairman
David R. Hill
Vice Chairman

Mr. Hill has more than 30 years of energy experience. In March 2025, he joined the non-profit Bipartisan Policy Center in Washington, DC as its Executive Vice President of Energy, leading the organization's Energy Program. He previously served as General Counsel of the U.S. Department of Energy, Executive Vice President and General Counsel of NRG Energy, Inc., and co-head of the energy practice at the international law firm, Sidley Austin LLP. He has served on the boards of directors of numerous community non-profit organizations. He holds a Bachelor of Science degree in Agricultural Journalism from the University of Missouri, and received his Juris Doctorate degree from the Northwestern University School of Law. 

 
Mark S. Lynch
Director
Mark S. Lynch
Director

Mark Lynch joined the Board of Directors in April 2018. He brings a wealth of executive and engineering experience from a very successful 41-year career in the energy industry, including serving as President and CEO of the New York Independent System Operator (NYISO) from 2005-2008.

 

Most recently, Mr. Lynch served as President and CEO of New York State Electric and Gas Corporation and Rochester Gas and Electric Corporation — both subsidiaries of AVANGRID, Inc. — from 2009 to 2017. He also served as a member of the Board of Directors for both regulated electricity and natural gas utility companies. From 2001-2004, he served as President of Mirant, New York, an independent power generation company that operated in competitive wholesale electricity markets in New York and New England.

 

Mr. Lynch’s experience also includes executive positions with Mississippi Power Company and Southern Energy, Inc. While with Southern Energy, he served as Executive President and Chairman of Empresa Electrica del Norte Grande, South America, and held positions in project development and management in Indonesia and North America. Mr. Lynch earned a Bachelor of Electrical Engineering degree from Villanova University.
Teresa Marrinan
Director
Teresa Marrinan
Director

Ms. Marrinan has 35 years of energy experience ranging from her entry-level role as a utility Rate Analyst to a Senior Vice President responsible for commercial operations for a large US generation fleet. She has served as a senior commercial executive focused on strategic planning, portfolio risk management and commercial operations in wholesale and retail US electricity markets.

Ms. Marrinan was Senior Vice President, US SBU Commercial for The AES Corporation, where she was responsible for US commercial operations and portfolio strategies for fossil-fired, wind, solar and energy storage resources across the US, and management of the unregulated retail electricity marketing business. Ms. Marrinan also was an officer of the Dayton Power and Light Company, responsible for fuel procurement and power trading, 24-hour real-time generation dispatch, logistics management of physical commodities and the company’s participation in organized ISO/RTO markets. Most recently, Ms. Marrinan serves as Founding Partner of Hanover Strategy Advisors LLC, where she advises a variety of clients on energy strategy, financial, regulatory and market issues.

Ms. Marrinan serves on the Board of Trustees for Goodwill Easter Seals Miami Valley, and as an adjunct professor in Economics and Finance at The University of Dayton School of Business Administration. She previously served as Board Chair of Foodbank Inc. and Cox Arboretum Foundation, and as a Board Member of the Premier Health Plan. Ms. Marrinan holds an MBA from Xavier University and a BS in Business Administration from the University of Dayton.
Gizman Abbas
Director
Gizman Abbas
Director

Mr. Abbas has nearly 30 years of energy and investment experience. Born in Ethiopia, he has lived or worked in New York since 2002 after joining Morgan Stanley in support of its energy and utilities, forest products / natural resources, and technology groups.

He is a founder of Direct Investment Development, a real estate investment firm based in New York City that is focused on sustainable development in underserved urban communities in the U.S.  He was also a founding partner of Twenty First Century Utilities, whose mission was to transform regulated utilities to a model of mass adoption of clean, low-cost, energy-producing and energy efficient technologies.

Mr. Abbas worked for Southern Company as a cooperative engineer while attending Auburn University, where he earned a Bachelor of Science degree in Electrical Engineering.  He also holds a Master of Business Administration in finance and accounting from the Kellogg Graduate School of Management at Northwestern University.  
Sally Talberg
Director
Sally Talberg
Director

Ms. Talberg has over 25 years of experience in the energy and environmental fields, with an emphasis on utility regulation and electricity markets. She serves as President & CEO at Michigan Saves, the nation's first non-profit green bank. As a former state commissioner and former adviser to commissioners at the Texas and Michigan commissions, she has a unique appreciation for the importance of market design, infrastructure planning, pragmatic regulation, and stakeholder engagement.
 
From 2013 through 2020, Ms. Talberg served as a Commissioner on the Michigan Public Service Commission. As Chair from 2016 until 2020, Ms. Talberg led the agency in formulating strategic priorities, oversaw approximately 180 employees, and managed a $25 million budget. She also represented the organization on various state, regional and national boards and committees. Ms. TaIberg has previously served as an Unaffiliated Board Member of the Electric Reliability Council of Texas and Michigan's lnteragency Environmental Justice Task Force. She holds a Bachelor of Science in Environmental and Natural Resources Policy Studies from Michigan State University and a Master of Public Affairs from the University of Texas at Austin. 
Michael Crowe
Director
Michael Crowe
Director

Mr. Crowe has 39 years of experience in software development, IT infrastructure, and cybersecurity with several private sector entities. From 2014 through 2022, Mr. Crowe served as the Chief Information Officer for the Colgate-Palmolive Company. In that role, he led the development of the company’s global IT strategy, modernized enterprise applications, and strengthened cybersecurity systems. In recognition of those accomplishments, Mr. Crowe was honored as a Top 50 Technology Professional in 2023 by OnCon. He currently serves as an advisor to several technology companies and is the Co-Chair of the Digital Supply Chain Institute – a research-based entity focused on enterprise supply chains in the digital economy.

Mr. Crowe holds a Bachelor of Science in Computer and Information Sciences from the University of Delaware. He also earned Executive Education Certificates from Dartmouth University and Stanford University.
Steve Doyon
Director
Steve Doyon
Director

Mr. Doyon has 39 years of experience in the energy industry, spending much of that time in various executive roles in both public and private energy generation companies. He is a resident of New York City and has been since 2008.

Before retiring in 2024, Mr. Doyon was the CEO of Onward Energy, a US based IPP focused on thermal and renewable generation, with over 6 GW of generation in 22 states. Prior to Onward, Mr. Doyon was the founder and CEO of Onward Energy’s predecessor company, Novatus Energy, since 2015. He also served on the Boards of both Novatus and Onward.

Mr. Doyon held executive leadership positions focused on development, finance, M&A, strategy, asset management, and operations at various other energy companies, including Terra-Gen Power, The AES Corporation, DTE, and Cogentrix Energy.

Mr. Doyon holds a Bachelor of Science in Environmental Engineering from the University of Florida, and a Master of Business Administration from The Fuqua School of Business at Duke University, where he was a Fuqua Scholar.
Heather Rivard
Director
Heather Rivard
Director

Ms. Rivard has more than 30 years of energy experience including her most recent role as the Senior Vice President, Transmission and Distribution, at Southern California Edison, where she was responsible for the operation, maintenance and modernization of SCE’s electrical grid.

Previously, Ms. Rivard was Senior Vice President of Electric Distribution at DTE Energy where she worked for 28 years. In this role, she was responsible for the distribution of electricity to 2.1 million customers across southeastern Michigan.

Before joining the utility industry, she worked as an aerospace engineer for the Department of Defense in Washington, D.C. and for NASA at the Johnson Space Center. She is the Past President and serves on the Executive Committee for the Association of Edison Illuminating Companies. 

Ms. Rivard holds a Bachelor of Science in Aerospace Engineering and an MBA from the University of Michigan.