Case study: Doral Renewables

CASE STUDY

Doral Renewables’ drive to build sustainable solar solutions

Read time: 8 min

Overview

Consumers and companies are using more power than ever. Among other factors, as the United States doubles down on AI (and data centers proliferate to keep pace), demand for energy continues to grow. Solar power has emerged as a clean, sustainable, and lower-cost energy option to help fill the need.

Northwest Indiana is proving to be one of the epicenters of this game-changing solar solution. It’s home to Mammoth Solar – the largest solar facility in the US, developed by Doral Renewables.

Fast take

Turning opportunity to reality

Over the years, the Mammoth Solar project has faced significant challenges, including shifting federal policies, COVID supply chain disruptions, and solar panel tariffs. McDermott worked closely with Doral to develop a clear strategy and successfully navigate these challenges.

The firm provided comprehensive legal guidance across PPA negotiations, tax equity financing, EPC contracting, and more. We secured more than $2 billion in debt and tax equity financing across multiple phases, renegotiated contracts to prevent delays, and managed complex tax structures. Mammoth North (phase one of the project) is complete and operational, with three phases nearly finished.

The project includes an innovative agrivoltaics program where local farmers use livestock to manage vegetation beneath solar panels, providing additional community benefits alongside the renewable energy production.

phases

$2billion

in financing

275K

homes to receive solar power

Renewable Deal of the Year,
Project Finance International America Awards 2025

Dual Use Plan of the Year,
North American Agrivoltaics Awards 2025

North America Renewables Deal of the Year 2024,
Proximo

Full story

A clear strategy to stay ahead

Challenge: A stormy landscape

In a win-win, Doral is building Mammoth to provide transformative solar energy while positively impacting the local community. Launched in 2019, the project spans four phases and, when fully operational, will power approximately 275,000 homes.

Through its years of development, the project has navigated several challenges.

Election cycles in the US have ushered in new administrations – along with accompanying policy and regulatory changes, such as shifting tax regimes, revised power purchase agreement (PPA) regulations, and the Inflation Reduction Act’s impact on tax credits. On a global scale, the COVID pandemic triggered supply challenges and market turmoil, while trade issues and tariffs on solar panels have introduced additional hurdles.

These conditions required a clear strategy that could anticipate challenges and overcome them to keep the project on track – from managing existing and new commercial agreements to creating new and innovative financing structures and preserving critical tax benefits.

Objective: Delivering sharp insights and success

Outcome: Here comes the sun

Mammoth North, the project’s first phase, is complete and operational, while the final three phases are nearly completed.

Doral has turned to McDermott for guidance on all aspects of developing and financing the facility. For each of the project’s four phases, our team assisted with PPAs, handled financing, and managed tax equity financing. Doral also engaged McDermott to work on EPC contracts, module supply agreements, services agreements, and credit facilities.

Finding ways to safeguard timelines and keep the project moving, despite unprecedented external challenges and pressures, was key to driving strategic management. As COVID threatened supply chains, we renegotiated essential contracts to avoid delays and ensure financial stability. With multiple stakeholders involved in the project, Doral trusted our team’s negotiating skills and experience to ensure coordination and consistent terms across phases.

Most critically – because a project at any scale will dry up when the dollars stop flowing – our team worked with Doral to secure debt and tax equity financing to the tune of more than $2 billion across multiple phases, which allowed construction to proceed without disruption. Our tax lawyers managed complex structures under an evolving IRA landscape to maintain the all-important tax benefits to investors. Their long track record of working on deals in the energy space, along with their single-minded focus on making things happen to support the client’s business, helped Doral get the project over the finish line.

Underpinning the partnership throughout was McDermott’s commitment to Doral’s goals: providing renewable energy and benefiting the local community and economy.

In addition to employing local construction workers and caterers, and renting housing in the area for other workers, Doral hired local farmers to manage the land under the solar panels, providing them with a stable revenue stream and additional income. Instead of growing crops on that land, the farmers use more than 2,000 pigs, sheep, donkeys, and alpacas to graze the land and manage vegetation beneath the solar panels (a dual-use operation known as agrivoltaics). Supporting this dual-use model required navigating land-use considerations, agricultural leasing dynamics, and long-term operational structures that aligned with lender and investor expectations.

The McDermott difference

McDermott’s work continues to support Doral Renewables and the Mammoth Solar project. Our guidance has helped keep Doral in the know and ahead of each potential obstacle. Our experience guiding Doral through shifting policy landscapes, supply-chain volatility, and phased financing equips us to help clients anticipate and navigate similar challenges across the energy industry.