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Executive Team

Executive Team

Our friends from the Canadian Peregrine Falcon Foundation were on @CP24 with their beautiful great horned owl, Alex… https://t.co/u1INS9KGBA

Mon Mar 18 18:53:15

RT @EarthRangers: The snow is starting to melt, which means it’s almost Plover season! Check out our piping plover project with @birdstudie…

Mon Mar 18 17:35:42

Great performance kids! You definitely had the luck of the Irish on your side. https://t.co/vj3ICPrkmV

Mon Mar 18 17:35:21

Jeffrey J. Lyash

President and Chief Executive Officer


Jeff Lyash is the President and CEO of Ontario Power Generation Inc. (OPG). OPG is one of the largest electrical generating companies in Canada with a diverse fleet of nuclear, hydroelectric, gas, biomass and renewable generating stations.

Lyash was formerly the President of CB&I Power where he was responsible for a full range of engineering, procurement and construction of multi-billion dollar electrical generation projects in both domestic and international markets. He also provided operating plant services for nuclear, coal, gas, oil and renewable generation.

Prior to joining CB&I, Lyash served as Executive Vice President of Energy Supply for Duke Energy. He led engineering, maintenance and operations of the company's 42,000-megawatt generation fleet, fuel procurement, power trading, major projects and construction, environmental programs, and health and safety programs.

Before the merger of Progress Energy and Duke Energy, Lyash served as Executive Vice President of Energy Supply for Progress Energy. In this role, he oversaw Progress Energy's diverse 22,000-megawatt fleet of generating resources including nuclear, coal, oil, natural gas and hydroelectric stations. In addition, he was responsible for generating fleet fuel procurement and power trading operations.

Lyash began his career in the utility industry in 1981, joining Progress Energy in 1993. Before assuming the role of Executive Vice President of Energy Supply, he served as Executive Vice President of Corporate Development, President and Chief Executive Officer of Progress Energy Florida, Senior Vice President of Energy Delivery Florida, and Vice President of Transmission. He also held a wide range of management and executive roles in Progress Energy's nuclear program, including Operations Manager, Engineering Manager, Plant Manager, and Director of Site Operations.

Before joining Progress Energy, Lyash worked for the U.S. Nuclear Regulatory Commission (NRC) in a number of senior technical and management positions throughout the northeast United States and in Washington, D.C, receiving the NRC Meritorious Service Award in 1987.

Lyash earned a Bachelor's Degree in Mechanical Engineering from Drexel University, and was honored with the Drexel University Distinguished Alumnus Award in 2009. He has held a Senior Reactor Operator Licence from the Nuclear Regulatory Commission, and is a graduate of the U.S. Office of Personnel Management Executive Training Program and the Duke Fuqua School of Business Advanced Management Program.

In 2018, Lyash was appointed Chair of the Electric Power Research Institute (EPRI), an international non-profit organization for public interest energy and environmental research. EPRI’s membership represents more than 1,000 organizations in 35 participating countries.

Sean Granville

Chief Nuclear Officer


Sean Granville is Chief Nuclear Officer (CNO) at OPG. Sean was appointed to this position on May 1, 2018, after two and a half years as Deputy CNO. Prior to this, Sean spent three years at Point Lepreau Nuclear Generating Station in New Brunswick as the Site Vice President and CNO. During his tenure with NB Power, the station achieved improvement as measured by the World Association of Nuclear Operators (WANO) Peer Review.

Sean's extensive background includes a 35-year career with OPG (and the former Ontario Hydro) holding positions such as Deputy Vice President, Director of Operations and Maintenance, and Director of Nuclear Programs. He was certified as a Licenced Shift Manager and has held Duty Manager positions at both Darlington and Pickering stations. Sean has expertise in areas such as operational leadership, leader development, performance improvement, organizational effectiveness, and industry engagement.

Sean’s nuclear industry experience also includes a secondment to WANO, serving on the Board of Directors of the Canadian Nuclear Association, and as a voting member of the Candu Owners Group.

Sean is a graduate of the University of Waterloo with a B.A.Sc. in Mechanical Engineering.

Mike Martelli, B.A.Sc., P. Eng., ICD.D

President, Renewable Generation


Mike Martelli is President, Renewable Generation at OPG. Mike was appointed to his current position in July 2013 and is responsible for leading a team of 1,500 skilled and dedicated team members who operate and maintain OPG’s two operating thermal stations, 66 hydroelectric generating stations and a solar project. These stations are located across Ontario and have total capacity of over 10,000 megawatts (MW).

Mike is a member of OPG’s Enterprise Leadership Team and an officer of the company. He has directed major projects including the Lower Mattagami, New Post Creek and Ranney Falls hydroelectric projects; fuel conversions of Atikokan Generating Station and Thunder Bay Generating Station from coal to biomass; and the Nanticoke Solar Project. Mike is also responsible for Corporate Indigenous Relations, working to build and maintain positive relationships with Indigenous communities throughout Ontario.

Mike manages OPG’s commercial partnerships with First Nation communities including Lac Seul First Nation, Moose Cree First Nation, Taykwa Tagamou Nation, Six Nations of the Grand River and Mississaugas of New Credit First Nation. These partnerships, which often involve joint ownership by both OPG and the First Nation communities, demonstrate a successful business model that generates economic growth and development for local communities while providing clean, renewable electricity for Ontario. Mike also serves on the boards of Portland Energy Centre; a joint venture between OPG and TransCanada that owns and operates a 550 MW combined cycle gas turbine generating station, and Brighton Beach Power; a joint venture between OPG and ATCO that owns and operates a 550 MW combined cycle gas turbine.

Mike joined OPG’s predecessor company, Ontario Hydro, in 1985. Since then he has held roles of increasing responsibility in both technical functions and plant operations at OPG site locations across Ontario including Timmins, Renfrew, Thunder Bay, Niagara Falls and Toronto. Mike’s previous management and executive roles include Maintenance Manager, Asset Manager, Director of Engineering, VP Operations-Thunder Bay, VP Operations-Niagara and SVP-Hydro-Thermal Operations.

A graduate of the University of Waterloo, Mike holds a B.A.Sc. in Mechanical Engineering. He is a Professional Engineer in Ontario and a graduate from the Institute of Corporate Directors. He is also a director on the board of the Canadian Hydropower Association.

Christopher F. Ginther

Chief Administrative Officer


Chris Ginther is Chief Administrative Officer at OPG. He joined the company in July 2012 as SVP and General Counsel and was appointed to his current position in February 2017.

Chris is responsible for the Regulatory, Procurement, Legal, Environmental, Real Estate and Facilities portfolios. Chris is a member of the OPG Enterprise Leadership Team and other committees.

Chris received his Bachelor of Arts Degree from the University of Western Ontario in 1983 and graduated from Osgoode Hall Law School in 1986. He received his Master of Laws Degree from Osgoode Hall in 1999.

Chris began his legal career at Torys LLP in Toronto. He has served as Vice-President and General Counsel at BCE/Bell and Chief Legal Officer at Ontario Lottery and Gaming Corporation.

Ken Hartwick, CPA

Chief Financial Officer and Senior Vice President


Ken Hartwick is Chief Financial Officer and Senior Vice President at OPG, leading all operations under Finance, Business Development, Strategy, and Risk.

Ken joined OPG in March 2016. His primary responsibilities are to provide leadership and support to OPG’s finance activities and to lead corporate development, strategic planning, and risk management. He also has accountability for financial strategy, controllership, accounting, reporting, business planning, investment planning, taxation, treasury, and pension and nuclear fund management.

Ken joined OPG from Wellspring Financial Corporation, where he was CFO and Treasurer. He was also interim President and CEO at Atlantic Power Corporation, a generating company that does business in Canada and the U.S. For ten years prior, Ken was the President and CEO of Just Energy Corporation, a Canadian-based energy retailer. In addition, he held the position of CFO at Hydro One between 2001 and 2004. He also held senior positions at Cap Gemini and was a partner at the accounting firm Ernst and Young.

Ken is a Chartered Professional Accountant with an Honours Bachelor of Business Administration. He serves on a number of boards.

Originally from Norwood, Ontario (near Peterborough), Ken now lives in Milton with his wife and has three grown children.

Barb Keenan

Senior Vice President, People and Culture, and Chief Ethics Officer


Barb Keenan is Senior Vice President, People and Culture, and Chief Ethics Officer at OPG. She was appointed to her current position in March 2010. Barb is responsible for the development of human resource strategies that support OPG’s business goals, including enhanced employee engagement, employer of choice through recruiting, succession planning and building successful relationships with OPG’s unions and partners. She is also responsible for strategies and programs supporting safety and employee wellness.

Barb joined Ontario Hydro, the predecessor company of OPG, in 1989 and has held various roles in Human Resources. Prior to her current appointment, Barb held the position of Vice President - Nuclear Human Resources and Employee Safety, and Vice President - Corporate Human Resources and Employee Safety. In these roles, Barb has been accountable for the overall management, leadership, direction and support for providing products and services designed to enhance business performance in the areas of leadership development, workforce and succession planning, recruitment, change management, employee communications and nuclear and corporate security. From 2000 – 2006, Barb worked with Capgemini Canada as Vice President – Human Resources for Outsourcing and later the broader organization.

Barb is an Honours Arts graduate from the University of Toronto, a Certified HR Planning Professional and a Certified Human Resources and Compensation Committee Director.

Dietmar Reiner, B.A.Sc., P.Eng.

Senior Vice President, Nuclear Projects


Dietmar Reiner is Senior Vice President, Nuclear Projects at OPG. Appointed to this position in May 2014, he is the senior corporate officer responsible for the vision, strategy, and leadership for planning and executing one of the world’s largest electricity infrastructure projects; the mid-life refurbishment of the Darlington Nuclear Generating Station.

Prior to this appointment, Dietmar was Senior Vice President, Nuclear Refurbishment, where he was responsible for establishing the Darlington Refurbishment Program.

Dietmar joined Ontario Hydro (OPG’s predecessor company) as an engineer in 1985 and proceeded to hold progressively senior positions in nuclear, hydroelectric and power systems.

In 1998, he served as a member on the technical panel of the Province’s electricity market design committee, where he led the design of the wholesale market rules and guidelines, which launched Ontario’s open electricity market.

In 1999, Dietmar was appointed to the position of Vice President, Commercial Systems where he was responsible for establishing the commercial infrastructure that enabled OPG to successfully compete in deregulated electricity markets. He also oversaw OPG’s preparations for the opening of Ontario’s electricity market.

In 2000, Dietmar was appointed to the position of Chief Information Officer, and led the transition of OPG’s internal information systems group to an outsourced services partnership.

In 2008, he was appointed to the position of Senior Vice President, Inspection, Maintenance & Commercial Services where he was responsible for providing specialized inspection and maintenance services to support the safe and reliable operation of OPG’s and Bruce Power’s nuclear generating fleets, as well as the management of OPG’s heavy water services and isotope sales businesses.

Dietmar has a Bachelor of Applied Science Degree in Honours Electrical Engineering from the University of Waterloo.

Jennifer Rowe

Senior Vice President, Corporate Affairs


Jennifer Rowe is Senior Vice President, Corporate Affairs at OPG. She was appointed to the role in January 2017.

Jennifer is responsible for building and managing relationships with OPG’s stakeholders, including senior officials and government stakeholders, industries, communities and the OPG Board. Her responsibilities also include developing corporate communications strategies that support OPG’s business goals.

Prior to joining OPG, Jennifer held numerous marketing, communications and corporate affairs positions in the financial services industry. Most recently, she was the Senior Vice President and Chief Marketing Officer at Meridian Credit Union. Previously, she served as Senior Managing Director, Marketing and Communications as well as VP Corporate Affairs at Manulife.

Jennifer has a Bachelor of Commerce degree from McMaster University and serves on the McMaster Governors and Alumni Association Board.