Brian Fellon, is a Senior Vice President at Xpansiv, where he leads all commercial activity for the firm’s Registry and Power Solutions business lines. Brian joined Xpansiv as Chief Commercial Officer of APX, following more than 15 years in the energy commodities sector as a power portfolio manager, trader, entrepreneur, and engineer. He previously served as VP of Strategy and Commercial Operations within Vestas Wind Systems’ renewable energy analytics division. Earlier in his career, Brian held a variety of commercial roles at Direct Energy, Hess Corporation, Sunoco, and Fellon-McCord. He has a B.S. in Mechanical Engineering from Drexel University and an MBA in Finance from Johns Hopkins University.
Dan Mullen, chair of Steptoe's Energy group, counsels clients on energy and commodities enforcement matters and government investigations and litigation, and assists clients with the development of energy regulatory compliance programs. Dan focuses on defending clients in investigations by the Federal Energy Regulatory Commission (FERC) and US Commodity Futures Trading Commission (CFTC).
Prior to joining Steptoe, Dan served as a Division of Investigations Branch Chief within the Office of Enforcement at FERC. In this position, he helped develop FERC's current enforcement regime and oversaw and conducted investigations and litigations against companies participating in the wholesale electricity and natural gas markets. Dan focused on investigations concerning energy market manipulation, reliability and violations of FERC-jurisdictional statutes, regulations and tariffs.
Dan is a frequent speaker at industry conferences, presenting on issues related to energy and commodity enforcement defense.
Yolanda E. Robles, International Transactional Attorney with over 20 years of experience in M&A, JVs, Divestitures, Risk Management, Corporate Law SME, Contracts and Energy Commodities Trading. Engaged in energy transition developments, including LNG, CCS, H2, and ESG compliance.
Keith M. Sappenfield II, is the Chair of Contracts Subcommittee of the Wholesale Gas Quadrant of the North American Energy Standard Board (NAESB). He has been an active member since NAESB’s inception (as the Gas Industry Standards Board) thirty years ago and has worked on development of most of its natural gas related standard contracts. He is currently leading NAESB’s work in developing a Standard Base Contract for the purchase and sale of Hydrogen. Concurrent with, and prior to, his NAESB participation he has worked for energy companies such as Cheneire Energy, EnCana Marketing, Reliant Resources (now part of NRG), BP Gas, and ANR Pipeline.
He is a Registered Professional Engineer (Civil) and an active member of the State Bars of Texas and Michigan and has worked in the field on operations as well as in the office on legal and regulatory matters.
Veronica Vaca, is a seasoned finance professional with over 20 years of experience in the energy sector. With a strong background in project valuation, she has worked extensively with multinational Oil and gas companies, driving investment strategies and financial planning across Latin America and the United States.
Currently, she serves as a Strategic Planner at Cobra Industrial Activities, specializing in economic and financial modeling to identify and develop new business opportunities in the hydrogen sector. Her expertise includes investment portfolio analysis, mergers and acquisitions, and joint ventures.
Prior to her current role, she held key positions at Shell, BG Group, and Baker Hughes, where she led business planning, financial performance management, and strategic investment analysis.
Veronica holds an MBA in Finance and multiple certifications related to the energy sector. She is fluent in Spanish and proficient in English and Portuguese. A member of AIEN since 2018, she has actively contributed as a peer reviewer for the Hydrogen Joint Development and Operating Agreement (JDOA) Term Sheet.
Chris Zentz, has a wide-ranging project development and energy regulatory practice that includes regular involvement in both energy transactions and regulatory proceedings. Chris enjoys working with a wide-ranging client base that reflects all sectors of the energy industry, including investor-owned utilities, public power entities, independent power producers, renewable project developers, investors, governmental entities, and power marketers. Chris’ experience extends to development of conventional and emerging technologies, including thermal, non-emitting, storage, transmission, and other, nascent technologies.
Chris’ transactional work focuses on representing clients in the negotiation of the material project contracts needed to build and finance generation projects. Chris uses his business background to formulate solutions-focused strategies for negotiating difficult and complex contractual arrangements. Chris’ experience extends to counselling clients in due diligence, and, where necessary, to advising on obtaining any required regulatory approvals at either the Federal or State levels.
Chris' regulatory practice focuses on assisting clients with various types of Federal regulatory compliance issues, including transmission and ancillary service rate cases, Open Access Transmission Tariff (OATT) implementation and compliance, generator interconnection issues, the FERC Standards of Conduct, interlocking directorate issues, and transmission planning. Similarly, as part of his transactional experience, Chris has significant experience advising clients seeking to develop or acquire projects through various FERC regulatory issues, such as obtaining market-based rate authorizations, prior-authorizations under Section 203 of the Federal Power Act, and advising on compliance with relevant Federal statutes such as the Public Utility Regulatory Policies Act (PURPA) and Public Utility Holding Company Act (PUHCA).
Having worked in-house and previously owned his own business, Chris can relate to the pressures, demands, and deadlines his clients face. Drawing on this experience, he brings a practical, solutions-focused approach to timely achieving his clients’ goals. Chris enmeshes himself in his clients’ businesses to better understand the underlying legal needs and goals, thereby allowing him to tailor his legal advice in a way that maximizes the chances of success and achieves his clients’ desired outcome in a practical and efficient manner.