Executive Officers

Anthony G. Petrello, 68
President, Chief Executive Officer, Secretary and Chairman

Mr. Petrello has served as the Chairman of the Board of Nabors since 2012 and director since 1991; Deputy Chairman of Nabors 2003—2012; President and CEO of Nabors and Nabors Industries, Inc. since 2011; President and Chief Operating Officer of Nabors and Nabors Industries, Inc. from 1991—2011. Mr. Petrello has served as the President, Chief Executive Officer, Secretary and Chairman of NETC I since March 2021. Mr. Petrello holds a J.D. degree from Harvard Law School and B.S. and M.S. degrees in Mathematics from Yale University. Mr. Petrello also serves as a director of Hilcorp Energy Company. In 2018, Mr. Petrello was the recipient of the Offshore Energy Center Pinnacle Award, recognizing outstanding individuals who have taken today’s leading-edge tools and technologies and applied them to real world challenges.

William J. Restrepo, 64
Chief Financial Officer

He has served as Chief Financial Officer of Nabors since March 2014. Mr. Restrepo has served as the Chief Financial Officer of NETC I since April 2021. Mr. Restrepo previously served as Chief Financial Officer at Pacific Drilling S.A. from February 2011 to February 2014. He also previously served as Chief Financial Officer at Seitel from 2005 to 2009, and at Smith from 2009 to 2010 until its merger with Schlumberger Limited. Prior to that, from 1985 to 2005, Mr. Restrepo served in various senior strategic, financial and operational positions for Schlumberger Limited, including operational responsibility for all product lines in the Continental Europe and Arabian Gulf markets, as well as senior financial executive roles in Corporate Treasury and worldwide controller positions with international posts in Europe, South America and Asia. Mr. Restrepo currently serves on the board of Reelwell As, a Norwegian-based provider of advanced drilling technology. He previously served on the board of directors of Saudi Aramco Nabors Drilling (Nabors’ joint venture with Saudi Aramco) and previously served on the boards of directors of C&J Energy Services Ltd. from 2015 to 2017, Probe Technology Services from 2008 to 2016, and Platinum Energy Solutions, Inc. from 2012 to 2013. Mr. Restrepo holds a B.A. in Economics and an M.B.A, both from Cornell University, as well as a B.S. in Civil Engineering from the University of Miami.

Board of Directors

Guillermo Sierra, 39
Vice President—Energy Transition

Mr. Sierra has served as the Vice President—Energy Transition of NETC I since April 2021. Mr. Sierra has extensive experience in energy infrastructure, venture investments, energy technology and climate technology, logistics, capital markets and M&A given his work on over 60 transactions with a combined value of over $200 billion over the last approximately 15 years through various advisory and corporate strategy roles. Mr. Sierra was a Partner at Blackline Partners from August 2019 to December 2020, serving as Executive Vice President, Head of Strategy for Blackline Midstream from August 2019 to March 2020 and in the same position for Blackline Cold Storage from March 2020 to November 2020. Mr. Sierra was not employed from December 2020 to April 2021. Prior to that, Mr. Sierra served as Managing Director, Head of North America Midstream Advisory at Macquarie Capital from September 2016 to December 2018 before taking a sabbatical from December 2018 to August 2019. Prior to Macquarie Capital, Mr. Sierra served as Senior Director, Head of MLP/?Midstream M&A at Credit Suisse from July 2015 to September 2016. Mr. Sierra’s earlier experiences include positions at USD Group LLC & USD Partners (VP, Chief Strategy Officer and Head of M&A), Evercore Partners (Vice President—Energy M&A), and Barclays Capital (as a member of the Global Natural Resources Group). Mr. Sierra is currently a Senior Advisor to the Chief Executive Officer, and board observer on the board of directors, of Sage Geosystems Inc., and is also a board observer on the board of directors of Quaise, Inc. Hephae Energy Technology and UCAP Power, Inc. Mr. Sierra graduated Cum Laude from the Wharton School of the University of Pennsylvania, where he received a B.S. in Economics with concentrations in Finance and Operations & Information Management.

Colleen Calhoun, 56
Director Nominee

Ms. Calhoun has served as Operating Partner at The Engine, an investment firm focusing on climate change human health and advanced systems and infrastructure, since April 2023. Ms. Calhoun previously served as Vice President of Spruce Power (formerly known as XL Fleet) (NYSE: SPRU), a provider of fleet electrification solutions, and General Manager of XL Grid, a division of Spruce Power, from January 2021 to February 2023. Prior to this, Ms. Calhoun served as Founder and Principal Advisor at Helios Consulting, LLC from November 2019 to December 2020. Ms. Calhoun spent twenty-five years at GE across several roles at the company, including Chief Marketing Officer and Head of Business Development (August 2018 to October 2019) and Head of Business Development and Partnerships (January 2016 to August 2018) at GE Current, a leading provider of energy efficiency and digital productivity solutions for commercial buildings and cities, where she was instrumental in the divesture of the business from GE in 2019; Global Senior Director of Energy Ventures at GE Ventures (January 2013 to December 2015); Executive Director, Marketing, Strategy and Project Development at GE Power & Water (October 2010 to December 2012); and Managing Director, Global Growth Markets at GE Energy Financial Services (January 2006 to September 2010). Ms. Calhoun is presently a member of the board of directors at Nabors Energy Transition Corp. and Quaise, Inc. and served on the board of directors of Evergreen Climate Innovations (formerly known as Clean Energy Trust) until February 2023. She also previously served on the Advisory Board at NYSERDA REV Connect. Ms. Calhoun earned her bachelor’s degree in engineering from the University of Pennsylvania and an MBA from the University of Michigan.

Stephen M. Trauber, 61
Director Nominee

Mr. Trauber served as the Vice Chairman & Global Head of Energy from January 2011 to March 2021 and subsequently Vice Chairman and Global Head of Natural Resources and Clean Energy Transition of Citigroup Global Markets Inc. from March 2021 until he retired in September 2022. Mr. Trauber served as Vice Chairman and Global Head of Energy at UBS Investment Bank from 2003 to 2010. Mr. Trauber has extensive experience serving as a strategic and financial advisor to companies transacting across all subsectors of the energy industry. He has worked on many of the most significant M&A transactions in these subsectors, with a transaction volume exceeding $500 billion. He was responsible for initiating and building the Global Clean Energy Transition Team at Citigroup Global Markets Inc. while serving as the Global Head of Natural Resources and Clean Energy Transition. He also played a key role in establishing Citigroup Global Markets Inc.’s plan for decarbonizing its financed emissions. In addition, Mr. Trauber has executed many significant financings across the energy sector. Mr. Trauber began his career with Credit Suisse First Boston (1988-1995) and subsequently managed Morgan Stanley’s Energy Group in Houston (1995-2003). Mr. Trauber has served on the Board of Directors of NEXT Renewable Fuels, Inc. since April 2023. Mr. Trauber received his BA in Economics and Managerial Studies from Rice University in 1984. He was an Austin Scholar and earned his MBA from the J. L. Kellogg Graduate School of Management at Northwestern University in 1988.

Colin Richardson, — [Appointed]
Director Nominee

He has served as a director of Vast Renewables Limited (Nasdaq: VSTE) since December 2023 and has served as a Managing Director at MA Financial Australia since 2013. He also sits on various investment committees for funds managed by MA Financial Group and is Chairman of MA Money, a residential mortgage origination company within the MA Financial Group. Mr. Richardson has over three decades of investment banking experience advising clients on mergers and acquisitions and strategic advisory transactions across a variety of industries. Mr. Richardson was previously a Managing Director at Rothschild, a Managing Director and Head of M&A for Australia and New Zealand at Citigroup and a Managing Director in M&A at Deutsche Bank. Prior to joining Deutsche Bank, Mr. Richardson worked at SG Hambros, formerly known as Hambros Bank, in Australia and London. He served on the board of Hockey NSW for three years, followed by three years on the board of Hockey Australia. He was also the inaugural Chair of Hockey 1, which is Australia’s premier domestic hockey competition. Mr. Richardson also holds positions on the boards of various Twynam Group Companies. Mr. Richardson holds a B.A. from Hull University.