Quanta Services : Puerto Rico Electric Transmission & Distribution System Operating & Maintenance Agreement Overview

Through its ownership in

Puerto Rico

Electric Transmission & Distribution System

Operating & Maintenance Agreement

Overview

June 22, 2020

Notice to Investors

This presentation (and oral statements regarding the subject matter of this presentation) includes forward-looking statements intended to qualify under the"safe harbor"from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements include any statements reflecting Quanta's expectations, intentions, strategies, assumptions, plans or beliefs about future events or performance or that do not solely relate to historical or current facts. Forward-looking statements involve certain risks, uncertainties and assumptions that are difficult to predict or beyond Quanta's control, and actual results may differ materially from those expected, implied or forecasted by our forward-looking statements due to inaccurate assumptions and known and unknown risk and uncertainties. For additional information concerning some of the risks, uncertainties, assumptions and other factors that could affect our forward-looking statements, please refer toQuanta'sAnnual Report on Form 10-K for the year ended Dec. 31, 2019, Quarterly Report on Form 10-Q for the quarter ended Mar. 31, 2020 and other documents filed with the Securities and Exchange Commission (SEC), which are available on our website (www.quantaservices.com), as well as the risks,uncertainties and assumptions identified in this presentation. Investors and analysts should not place undue reliance onQuanta's

forward-looking statements, which are current only as of the date of this presentation. Quanta does not undertake and expressly disclaims any obligation to update or revise any forward-looking statements to reflect events or circumstances after the date of this presentation or otherwise, and Quanta expressly disclaims any written or oral statements made by any third party regarding the subject matter of this presentation.

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Opportunity Highlights

• •LUMA Energy, LLC (LUMA), 50% owned by Quanta and 50% owned by ATCO, has been selected for this historic opportunity-the transformation and modernization of the Puerto Rico electric transmission and distribution (T&D) system, in order to provide significant benefits to the people of Puerto Rico through an Operation and Maintenance Agreement (O&M Agreement) with the Puerto Rico Electric Power Authority (PREPA) and the Puerto Rico Public-Private Partnership Authority (P3)

• •LUMA is a purpose-built company that leverages the strengths of Quanta, ATCO and IEM, including world-class utility operations; craft-skilled labor training and management; and federal funds procurement, management and deployment

• •LUMA's O&M Agreement is consistent with Quanta's long-term strategy

  • •Long-term, contracted agreement that is expected to provide a visible, recurring and resilient cash flow and earnings stream

  • •LUMA earns a fixed fee for service plus opportunity to earn annual incentive fees based on achievement of performance metrics. PREPA retains ownership of the electric T&D system and LUMA is not required to make capital investments in the electric T&D system

  • •Electric T&D system operating costs and capital expenditures are pass-through and paid from pre-funded serviceaccounts

• •Quanta believes there is opportunity for it to compete for work associated with Puerto Rico's grid modernization effortsthat are separate from its ownership interest in LUMA

• •Successful collaboration with a customer to deliver unique infrastructure solutions that can serve as a blueprint for futureopportunities

  TRANSFORMATIVE OPPORTUNITY FOR THE PEOPLE OF PUERTO RICO AND QUANTA

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Puerto Rico Electric T&D System Operation & Maintenance Agreement

Summary

In response to the devastation of the island and its electric power system caused by hurricanes in 2017, as well as other challenges faced by PREPA, in June 2018, Puerto Rico began a historic process intended to transform and further modernize the electric power grid and PREPA into an organization that is (1) customer-centric, (2) affordable, (3) reliable, (4) resilient, and (5) sustainable.

To that end, Puerto Rico government agencies pursued a partnership with a private entity for a long-term agreement to operate and maintainPREPA'sentire electric transmission and distribution (T&D) system and to lead the transformation of PREPA. LUMA competed for and was formally selected by the P3 to be the operator for the agreement in June 2020. Additional information can be found on the P3 website athttp://www.p3.pr.gov/.

Selection Process Timeline

LUMA short listed

RFQ issuedas one of four proponentsFormal bid submitted

LUMA award recommended

Jun. 2018

Oct. 2018

Nov. 2018

Jan. 2019

Feb. 2019

LUMA Diligence

Nov. 2019

Jan. 2020

May 2020

June 2020

P3 market sounding for T&D system

LUMA submits qualificationsRFP issued

LUMA selected preferred bidder

Govt. approval & final transaction documents

LUMA TO UNDERTAKE HISTORIC TRANSFORMATION OF PUERTO RICO T&D SYSTEM

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LUMA's Expected Benefits to the People of Puerto Rico

LUMA is a purpose-built company that has been designed to help provide the people and communities of Puerto Rico with a resilient, reliable and sustainable electric T&D system, while also delivering outstanding customer service. Over the contract term, LUMA will collaborate to deliver a modern and sustainable workforce and grid for Puerto Rico. LUMA is committed to high standards of transparency, integrity, safety and operational excellence

• •LUMA is making a long-term commitment to the people of Puerto Rico and-with its partners-is focused on becoming acustomer-centric utility that is a part of the Puerto Rico community.

• •LUMA is taking a tailored approach to the implementation of plans for emergency preparedness and response and the further modernization of the T&D system

• •LUMA expects improved electricity affordability for the people and businesses of Puerto Rico over time and improving customer service and reliability programs

• •LUMA will seek to create economic benefits that attract businesses, create job opportunities and improve quality of life in Puerto Rico

• •LUMA will leverage its extensive experience with federal funding procurement, management and deployment

• •LUMA has made a strong commitment to Puerto Rico's utility workforce through developing and managing a state-of-the-artline worker and technical training campus in Puerto Rico. The campus will be operated by Quanta's accredited postsecondaryeducational institution - Northwest Lineman College - and plans to offer world-class, customized curriculum and training to

  LUMA utility workers and the next generation of Puerto Rico's skilled workforce

DESIGNED TO DELIVER SIGNIFICANT BENEFITS TO THE PEOPLE OF PUERTO RICO

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