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1025 Thomas Jefferson St, NW
8th Floor, West Tower
Washington, DC 20007-5201

202.342.0800 Phone
202.342.0807 Fax

Peter J. Mattheis principal

For 25 years, Pete Mattheis has been providing legal and practical advice to clients in the energy arena, developing creative solutions for a broad array of clients, all seeking to control their power costs. The knowledge gained through these many engagements in varied markets enable Pete to act as a bridge between the producers/transmitters of power and consumers of power to obtain the lowest cost of electricity possible for his clients.

Pete has negotiated power supply and related contracts on behalf of large industrial energy users and public power entities, has participated in state and federal rate proceedings, utility merger proceedings, and other regulatory proceedings to protect industrial client interests and has helped clients evaluate power market opportunities. Pete also assists clients in evaluating the impact of utility resource and fuel use decisions, state and federal energy-related legislation, and FERC and NERC regulations. Additionally, he has assisted industrial clients in the siting of industrial facilities, including arranging for electric power and natural gas supply, railroad and port arrangements, infrastructure improvements, and state and local economic incentives.

Clients rely on Pete’s consultation and evaluation of electricity supply issues, knowing that he’s seen virtually every problem large industrial power consumers can experience and has the insight and expertise to develop and implement creative solutions. Pete currently serves as the chairman of the Tennessee Valley Industrial Committee, the voice of large, energy-intensive industries in the Tennessee Valley Authority (TVA) power service area that purchase electricity directly from TVA.

Electric and Natural Gas Utility Law

Stone Mattheis Xenopoulos & Brew, PC represents wholesale and retail purchasers of electricity and natural gas in determining optimal energy strategies, in contract and transactional matters, and in litigation before federal and state courts and agencies. We are counsel to many industrial users of electricity and natural gas as well ...
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The firm has decades of proven litigation and trial experience spanning numerous disciplines and in multiple venues – administrative, trial court and appellate. In the regulatory arena, firm attorneys have extensive trial experience at both the state and federal levels related to energy and other issues before administrative agencies. At the ...
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Public Policy and Law

Stone Mattheis Xenopoulos & Brew, PC offers its clients government relations services related to its overall energy regulatory practice.  We monitor and assist clients in participating in legislative and regulatory developments that may impact their operations on the federal and/or state level. Specific government relations services include:
  • Legislative, regulatory, and executive ...
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  • Represented an industrial client in creating a new utility product utilizing a specific and purpose-driven supply arrangement that kept costs low for the consumer and provided additional value and flexibility for the supplier.
  • Renegotiated a power supply contract for a steel mill client that produced significant cost, service and operational benefits for the mill, while maintaining the original contract’s industry standard setting components.
  • Convinced a utility to implement new tariff options with strong cost control benefits to his client, with the anticipation, later realized by the utility, that the rate structure would also have appeal to other power consumers in the same system.