Maceira Zayas (MZLS) guides energy developers, investors, and operators through Puerto Rico's regulatory framework and the federal layer above it, from project development through compliance and litigation. The firm's attorneys served within the institutions that built that framework. Now they represent the private sector operating inside it.
MZLS represents energy developers, investors, and operators in Puerto Rico's regulatory system and before the federal agencies that fund and oversee it. The attorneys combine regulatory practice before the Puerto Rico Energy Bureau (PREB), environmental and permitting depth, and Washington advocacy, covering every stage from permitting and procurement through compliance, litigation, and federal coordination.
What We Do
Regulatory & Administrative Counsel
Representation before the Puerto Rico Energy Bureau (PREB) and the Public Service Board: licensing, rate cases, interconnection approvals, administrative appeals, rulemakings, and compliance audits aligned with DOE and FERC oversight.
Environmental & Permitting for Energy Projects
Environmental and permitting work before DRNA and the EPA, including EIS preparation, waste and water permitting, and compliance for renewable, LNG, and distributed-generation projects. The firm's matters include the 2017 coal-ash litigation.
Public-Private Partnerships & Procurement
The team helped deliver the first FEMA-funded energy project under a full P3 concession and, as consultants to the P3 Authority, worked on the procurement manuals for the LUMA Energy and Genera PR transactions. The practice covers RFP compliance, bid evaluation, contract negotiation, and post-award administration.
Federal Government Affairs & Energy Policy Advocacy
With offices in San Juan and Washington, D.C., the firm advocates before DOE, EPA, and FEMA for approvals, funding, and interagency coordination, and engages Congress on Puerto Rico's energy and resilience priorities.
Regulatory Compliance & Risk Management
Compliance counsel for energy operators under PREB, EPA, OSHA, and federal grant requirements: audits, internal controls, and responses to agency inquiries and enforcement actions.
Energy Contracts & Commercial Structuring
Drafting and negotiation of power purchase agreements, fuel supply contracts, and EPC arrangements built to meet financing standards and regulatory scrutiny in Puerto Rico.
Energy Litigation & Dispute Resolution
Disputes before PREB, Puerto Rico courts, and federal forums: rate challenges, interconnection denials, and procurement disputes, from administrative filings through appellate review.
Project Development & Transaction Support
Support for LNG, solar, hydro, and microgrid projects from concept to operation: permitting, land use, interconnection, finance, and joint-venture structuring.
Policy & Oversight Advisory
As Puerto Rico's Secretary of Public Affairs, Anthony O. Maceira led the team that secured approval of Act 17-2019, the Puerto Rico Energy Public Policy Act, from the governor's office. The firm has also served as legal counsel to the Public Service Board, which oversees PREB. That experience informs how the firm positions projects within Puerto Rico's energy transition.
Few firms pair policy authorship with daily regulatory practice. The firm's attorneys helped shape the framework that governs today's market, advised the agencies that enforce it, and now represent the private parties operating within it. The work runs from federal clearances for generation projects and PREB proceedings to P3 concessions and compliance disputes. MZLS moves projects from concept to operation.
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2026 Congressional Calendar
The 2026 Congressional Calendar was officially released! Access the combined House and Senate schedules now — downloadable files with full-year and monthly below.
