Principal Mechanical Engineer - Thermal Projects

Are you ready to be part of a company that's not just talking about the future, but actively shaping it? Join The AES Corporation, the largest US-based global power company with a team of 8,300 employees across 12 countries.

AES has been ranked #1 by BloombergNEF in renewable energy sales to corporations in the US and Americas for five consecutive years, providing electricity for millions of people worldwide.

We are proud to foster a strong workplace culture, earning prominent positions in Great Place to Work™ rankings across the markets where we operate. AES was also named one of the World’s Most Ethical Companies for the 13th consecutive year in 2026, highlighting our dedication to integrity, transparency, and responsible business practices.

Our spirit of innovation continues to earn industry recognition. AES is the only seven-time winner of the Edison Electric Institute’s Edison Awards in the twenty-first century, a distinction honoring global leadership in advancing the electric power industry.

If you're ready to be part of a company that's not just adapting to change, but driving it, AES is the place for you. We're not just building a more sustainable future, we're powering it. Apply now and energize your career with a true leader in global energy.

The Principal Mechanical Engineer - Thermal Projects will be responsible for providing subject matter expertise and technical leadership for the mechanical design and engineering of thermal power generation projects in development, construction, and operation. Responsibilities include technical oversight of third-party engineering, design reviews, contract document development and negotiation, procurement specification preparation, and other technical support activities.

The Principal Mechanical Engineer will join a team of project engineers reporting to the Director of Engineering and will serve as the mechanical subject matter expert supporting thermal projects across the portfolio. Additional responsibilities include mentoring and training other Engineers, directly supporting projects as a subject matter expert, providing technical guidance and resolving complex mechanical engineering issues, driving innovation within the team, and driving institutional change within the wider organization.

The successful candidate will have a depth of experience in the development, analysis, and design of thermal generation facilities, including gas turbines, reciprocating internal combustion engine (RICE) power plants, combined-cycle facilities, simple-cycle generation, cogeneration systems, hybrid thermal generation projects, heat recovery steam generators (HRSGs), steam turbines, and associated thermal balance-of-plant systems. Experience with related technologies and infrastructure, including natural gas and LNG systems, electrical interconnections, battery energy storage systems (BESS), microgrids, renewable energy integration, and data center power solutions, is highly desirable. Experience with other generation technologies including renewable energy, nuclear, hydroelectric, or emerging energy technologies is a plus. Excellent communication, task management, and planning skills are needed, in addition to technical depth and breadth.

Key Responsibilities

Project Execution

• Develop, review, and support engineering for gas and steam turbines, HRSGs, fuel-gas systems, cooling systems, water treatment, compressed air, fire protection, HVAC, piping, pumps, heat exchangers, and mechanical balance-of-plant.
• Prepare and review design criteria, calculations, drawings, specifications, data sheets, technical reports, cost estimates, and scopes of work.
• Coordinate interfaces with civil, structural, electrical, mechanical, controls, environmental, operations, construction, and commissioning disciplines.
• Review EPC, consultant, OEM, and vendor work products for compliance with project requirements, codes, standards, contracts, and expected deliverables.
• Perform technical studies, equipment selection, design optimization, constructability, and value-engineering evaluations.
• Support procurement through technical bid evaluations, vendor-document review, inspections, factory testing (FAT), and issue resolution.
• Provide field engineering support and review installation for conformance with approved documents, quality requirements, and safe work practices.
• Investigate design, fabrication, construction, software, and commissioning issues and develop practical technical resolutions.
• Support project schedule, budget, risk, interface, and management-of-change activities.
• Support mechanical completion, Site Acceptance Testing (SAT), testing, energization, commissioning, startup, performance verification, and turnover.
• Maintain technical baselines, redlines, approved changes, test records, and as-built documentation.
• Prepare training and operating information and transfer knowledge to project and plant personnel.
• Capture lessons learned and improve standards, templates, and reference designs.
• Travel to engineering offices, vendor facilities, and project sites as required.
• Review and evaluate major equipment performance guarantees, reliability guarantees, availability guarantees, operating constraints, heat rate performance, emissions requirements, and project design assumptions.
• Support fuel supply and infrastructure evaluations, including natural gas and LNG systems, in coordination with internal and external stakeholders.
• Support permitting and environmental activities by providing technical input related to plant design, equipment selection, operating profiles, and emissions characteristics.
• Support Operations/Asset Management teams to resolve mechanical and thermal technical issues at operating sites.
• Mentor and provide technical guidance to engineers on thermal generation and mechanical engineering topics.

Growth and Leadership

• Contribute to process improvement initiatives for the execution of safe, quality, and high-performance projects.
• Provide timely feedback on EPC and external engineer performance, and document lessons learned to influence internal process enhancements.
• Mentor and educate team on changing trends in technology, best practices, code enforcement, and safety.
• Direct mentorship of other Engineers on job requirements and technical acumen.
• Support the team as a technical subject matter expert.
• Support evaluation of emerging technologies and companies for the Approved Vendor List.
• Lead technical evaluations of new thermal generation technologies and provide recommendations to support project development, technology selection, and long-term business strategy.

Safety

• Attend site safety walks and identify jobsite hazards.
• Obtain and maintain safety training certifications (NFPA 70E, OSHA 10-hour, and CPR/first aid).
• Lead by example.

Skills and Qualifications

Primary Qualifications

• Undergraduate degree in mechanical engineering or equivalent technical field.
• 10 or more years of mechanical engineering experience in power generation, oil and gas, industrial, or major capital projects.
• Ability to interpret P&IDs, equipment drawings, piping specifications, layouts, and vendor documents.
• Ability to coordinate cross-functional teams and resolve complex technical, commercial, or execution issues.
• Engineering design experience with thermal power generation facilities, including gas turbines, RICE power plants, combined-cycle facilities, simple-cycle facilities, cogeneration systems, HRSGs, steam turbines, and associated balance-of-plant systems.
• Ability to evaluate technical decisions with consideration for cost, schedule, constructability, operability, maintainability, and project risk.
• Experience reviewing operations and maintenance requirements, maintenance philosophies, outage planning considerations, and long-term asset performance expectations.
• Strong communication and interpersonal skills, including ability to successfully work cross-functionally across a large organization.
• Self-starter with ability to work effectively in a remote and/or distributed team environment.
• Ability to effectively manage third party consultants, vendors, and internal stakeholders.
• Proficient with MS Office Suite.
• Direct project experience with Procore.

Plus Qualifications

• Graduate degree in mechanical engineering
• EIT or PE qualifications
• Knowledge of thermal power plant codes, standards, and industry practices
• Experience with air permitting, emissions compliance, and environmental regulations applicable to thermal generation facilities
• Understanding of generator interconnection processes and grid compliance requirements
• Experience with fuel systems, including natural gas and LNG infrastructure
• Experience with ETAP, SKM, AspenTech, GT PRO, Thermoflow, or other advanced power system and thermal performance modeling tools
• Substation/High Voltage design experience
• Structural/SCADA/commissioning engineering design experience
• Experience with AutoCAD Civil3D
• Fluency in Spanish

AES is an Equal Opportunity Employer who is committed to building strength and delivering long-term sustainability through diversity and inclusion. Respecting all backgrounds, differences and perspectives enables us to improve the lives of our people, customers, suppliers, contractors, and the communities in which we live and work. All qualified applicants will receive consideration for employment without regard to sex, sexual orientation, gender, gender identity and/or expression, race, national origin, ethnicity, age, religion, marital status, physical or mental disability, pregnancy, childbirth, or related medical condition, military or veteran status, or any other characteristic protected under applicable law. E-Verify Notice: AES will provide the Social Security Administration (SSA) and if necessary, the Department of Homeland Security (DHS) with information from each new employee's I-9 to confirm work authorization.