CrawlJobs Logo

Senior Principal Mechanical Engineer

United Kingdom, Derby · Job Posted June 15, 2026
Apply Position
Job Link Share

Job Description

Join the Fusion and Modular Nuclear Business Unit! Take on a pivotal role in shaping the future of clean energy by establishing, leading, and managing the Cooling Water Island engineering team within a groundbreaking Small Modular Reactor (SMR) development program. Drive the development of a high-performing team, overseeing the design, integration, and execution of critical cooling water systems essential to reactor operation. Play a key role in defining technical strategies, ensuring regulatory compliance, and collaborating across multidisciplinary teams to deliver innovative, high-efficiency engineering solutions that will help revolutionize nuclear power.

Job Responsibility

  • Leadership of the Engineering Activities of the Cooling Water Team – Lead and mentor a team of engineers, driving technical excellence, innovation, and collaboration to deliver critical cooling water systems for the Small Modular Reactor (SMR) program
  • Development of Safety and Functional Requirements – Define and establish rigorous safety and performance criteria, ensuring compliance with industry regulations and best practices to support safe and reliable reactor operation
  • Design Package Production in Line with Requirements – Oversee the creation of comprehensive design packages, ensuring alignment with project specifications, technical standards, and operational needs
  • Management of Interfaces – Coordinate effectively between engineering teams, suppliers, and stakeholders to ensure seamless integration of cooling water systems with other reactor components
  • Preparation of Technical Specifications – Develop clear, detailed technical specifications to guide procurement, fabrication, and installation of key cooling water system components
  • Maintain Equipment Lists and Schedules – Track, update, and manage critical equipment inventories and project schedules to ensure timely delivery and smooth execution of engineering activities
  • Management of Risk and Opportunity – Proactively identify potential risks and opportunities, implementing strategies to mitigate challenges and optimize system performance, cost-effectiveness, and overall project success

Requirements

  • FEED to Detailed Design Experience – Proven expertise in leading projects from Front-End Engineering Design through to execution
  • Multi-Disciplinary Team Leadership – Skilled in managing and coordinating diverse engineering teams
  • Steam Cycle Modelling Oversight – Ability to define modelling outcomes and ensure accurate implementation
  • Project Budget & Lifecycle Planning – Experienced in budgeting and planning for full design lifecycles
  • Cooling Water Equipment Expertise – Strong track record in designing and optimizing cooling water systems
  • Regulatory & Compliance Knowledge – Well-versed in ONR, Environment Agency, and HSE regulations
  • Requirements Capture Experience – Skilled in gathering and defining technical requirements
  • Systems Engineering Awareness – Strong understanding of integrated design principles
  • Subcontractor Management – Experienced in overseeing and coordinating subcontractors
  • Chartered Engineer (CEng) – Professional accreditation in a relevant discipline
  • Security Clearance Eligibility – Capable of obtaining SC clearance for secure projects

What we offer

  • Attractive social benefits, including an engaging Employee Committee and holiday bonuses
  • Ongoing training with numerous career opportunities
  • 70% of our managers are promoted internally
  • Hybrid work: 1-2 days remote per week

Looking for more opportunities?

Search for other job offers that match your skills and interests.

Similar Jobs for

Senior Principal Mechanical Engineer

8 matching positions

Senior Principal Mechanical Engineer

Join the Fusion and Modular Nuclear Business Unit! Take on a pivotal role in sha...
Location
Location
United Kingdom , Newcastle upon Tyne
Salary
Salary:
Not provided
assystem.com Logo
ASSYSTEM
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • FEED to Detailed Design Experience
  • Multi-Disciplinary Team Leadership
  • Steam Cycle Modelling Oversight
  • Project Budget & Lifecycle Planning
  • Cooling Water Equipment Expertise
  • Regulatory & Compliance Knowledge
  • Requirements Capture Experience
  • Systems Engineering Awareness
  • Subcontractor Management
  • Chartered Engineer (CEng)
Job Responsibility
Job Responsibility
  • Leadership of the Engineering Activities of the Cooling Water Team
  • Development of Safety and Functional Requirements
  • Design Package Production in Line with Requirements
  • Management of Interfaces
  • Preparation of Technical Specifications
  • Maintain Equipment Lists and Schedules
  • Management of Risk and Opportunity
What we offer
What we offer
  • Attractive social benefits, including an engaging Employee Committee and holiday bonuses
  • Ongoing training with numerous career opportunities
  • 70% of our managers are promoted internally
  • Hybrid work: 1-2 days remote per week
  • Fulltime
Read More
Arrow Right

Senior Principal Mechanical Engineer

Assystem has an exciting opportunity for a Senior Principal Mechanical Engineer ...
Location
Location
United Kingdom , Bolton
Salary
Salary:
Not provided
assystem.com Logo
ASSYSTEM
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • Multi-Disciplinary Team Leadership – Skilled in managing and coordinating diverse engineering teams
  • Steam Cycle Modelling Oversight – Ability to define modelling outcomes and ensure accurate implementation
  • Project Budget & Lifecycle Planning – Experienced in budgeting and planning for full design lifecycles
  • Cooling Water Equipment Expertise – Strong track record in designing and optimizing cooling water systems
  • Regulatory & Compliance Knowledge – Well-versed in ONR, Environment Agency, and HSE regulations
  • Requirements Capture Experience – Skilled in gathering and defining technical requirements
  • Systems Engineering Awareness – Strong understanding of integrated design principles
  • Subcontractor Management – Experienced in overseeing and coordinating subcontractors
  • Chartered Engineer (CEng) – Professional accreditation in a relevant discipline
  • Security Clearance Eligibility – Capable of obtaining SC clearance for secure projects
Job Responsibility
Job Responsibility
  • Lead and support the development of designs for the following systems: Personnel Airlocks, Main Equipment Access Hatch, Fuel Transfer Channel, Piping Penetrations, Electrical Penetrations, Specialist Nuclear Doors
  • Conduct DFMEA (Design Failure Mode and Effects Analysis) to identify and mitigate potential failure modes early in the design process
  • Perform HAZID (Hazard Identification Study) to assess and document risks across the system
  • Complete and maintain Human Factors Checklists to ensure ergonomics and usability are considered in design decisions
  • Update and manage the project’s Risk Register to track, evaluate, and mitigate emerging risks
  • Design Package Production in Line with Requirements – Oversee the creation of comprehensive design packages, ensuring alignment with project specifications, technical standards, and operational needs
  • Management of Interfaces – Coordinate effectively between engineering teams, suppliers, and stakeholders to ensure seamless integration of cooling water systems with other reactor components
  • Preparation of Technical Specifications – Develop clear, detailed technical specifications to guide procurement, fabrication, and installation of key cooling water system components
  • Collaborate with cross-functional teams, including both new and existing FTEs and secondees across engineering and project functions
What we offer
What we offer
  • Over 55 years in nuclear engineering
  • Ranked among the top 3 largest nuclear engineering companies
  • Attractive social benefits, including an engaging Employee Committee and holiday bonuses
  • Ongoing training with numerous career opportunities
  • 70% of our managers are promoted internally
  • Hybrid work: 1-2 days remote per week
  • Fulltime
Read More
Arrow Right

Senior Principal Mechanical Engineer

🚀 Join the Fusion and Modular Nuclear Business Unit! 🚀 Take on a pivotal role ...
Location
Location
United Kingdom , Warrington
Salary
Salary:
Not provided
assystem.com Logo
ASSYSTEM
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • FEED to Detailed Design Experience – Proven expertise in leading projects from Front-End Engineering Design through to execution.
  • Multi-Disciplinary Team Leadership – Skilled in managing and coordinating diverse engineering teams.
  • Steam Cycle Modelling Oversight – Ability to define modelling outcomes and ensure accurate implementation.
  • Project Budget & Lifecycle Planning – Experienced in budgeting and planning for full design lifecycles.
  • Cooling Water Equipment Expertise – Strong track record in designing and optimizing cooling water systems.
  • Regulatory & Compliance Knowledge – Well-versed in ONR, Environment Agency, and HSE regulations.
  • Requirements Capture Experience – Skilled in gathering and defining technical requirements.
  • Systems Engineering Awareness – Strong understanding of integrated design principles.
  • Subcontractor Management – Experienced in overseeing and coordinating subcontractors.
  • Chartered Engineer (CEng) – Professional accreditation in a relevant discipline.
Job Responsibility
Job Responsibility
  • Leadership of the Engineering Activities of the Cooling Water Team – Lead and mentor a team of engineers, driving technical excellence, innovation, and collaboration to deliver critical cooling water systems for the Small Modular Reactor (SMR) program.
  • Development of Safety and Functional Requirements – Define and establish rigorous safety and performance criteria, ensuring compliance with industry regulations and best practices to support safe and reliable reactor operation.
  • Design Package Production in Line with Requirements – Oversee the creation of comprehensive design packages, ensuring alignment with project specifications, technical standards, and operational needs.
  • Management of Interfaces – Coordinate effectively between engineering teams, suppliers, and stakeholders to ensure seamless integration of cooling water systems with other reactor components.
  • Preparation of Technical Specifications – Develop clear, detailed technical specifications to guide procurement, fabrication, and installation of key cooling water system components.
  • Maintain Equipment Lists and Schedules – Track, update, and manage critical equipment inventories and project schedules to ensure timely delivery and smooth execution of engineering activities.
  • Management of Risk and Opportunity – Proactively identify potential risks and opportunities, implementing strategies to mitigate challenges and optimize system performance, cost-effectiveness, and overall project success.
What we offer
What we offer
  • Attractive social benefits, including an engaging Employee Committee and holiday bonuses
  • Ongoing training with numerous career opportunities
  • 70% of our managers are promoted internally
  • Hybrid work: 1-2 days remote per week
  • Fulltime
Read More
Arrow Right

EC&I Designer, Engineer, Senior Engineer, Principal Engineer

Step into a career-defining role with Actemium Design, specialists in engineerin...
Location
Location
United Kingdom , Chorley and Whitehaven
Salary
Salary:
Not provided
vinci-energies.com Logo
VINCI Energies
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • Relevant engineering degree (e.g., electrical, electronic, control, instrumentation), HNC/HND, or equivalent professional experience in EC&I design/engineering
  • Solid understanding of CAD design, industrial electrical systems, instrumentation, and controls design
  • Experience producing and reviewing EC&I schematics, wiring diagrams, loop drawings, cable schedules, and panel layouts
  • Proficiency in relevant software (e.g., AutoCAD, EPLAN, Amtech/Trimble, or similar tools)
  • Knowledge of UK electrical standards and good practice
  • Proactive, organised, and adaptable approach with strong teamwork and communication skills
  • For senior/principal roles: proven ability to lead projects, mentor others, and act as technical authority on EC&I design solutions
  • Full UK driving licence or ability to travel to client sites as required
Job Responsibility
Job Responsibility
  • Develop, review, and improve Electrical, Control & Instrumentation (EC&I) designs for nuclear and non-nuclear projects
  • Carry out detailed engineering calculations, equipment sizing, instrument selection, and preparation of technical documentation (drawings, schedules, data sheets, specifications)
  • Collaborate with multi-disciplinary teams (mechanical, process, project management) to ensure seamless integration and delivery
  • Engage with clients, and site teams to clarify requirements, resolve technical queries, and drive engineering excellence
  • Mentor and support junior engineers/designers, championing knowledge-sharing and continuous improvement
What we offer
What we offer
  • Competitive salary package depending on role and experience
  • Pension contributions
  • Discretionary annual bonus
  • Heath Shield plan
  • 26 days holiday plus bank holidays
  • EV car scheme
  • Company share scheme (qualifying periods apply)
  • Death in service insurance
  • Hybrid and flexible working arrangements where applicable
  • Supported training
  • Fulltime
Read More
Arrow Right

Senior / Principal Mechanical Engineer

ACTEMIUM Design offers multidiscipline design expertise which enables us to deli...
Location
Location
United Kingdom , Chorley
Salary
Salary:
Not provided
vinci-energies.com Logo
VINCI Energies
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • Questioning attitude, confident to challenge information where needed
  • Previous experience in design substantiation and safety case involvement for highly regulated industries
  • Fully familiar with all aspects of safety case methodologies and legal framework relevant to nuclear safety
  • Good oral and written communication skills, including presentation and report writing
  • Several years' experience working in design engineering
  • Degree with honours or Level 6 equivalent
  • Chartered Engineer or equivalent (or working towards)
Job Responsibility
Job Responsibility
  • Authoring nuclear substantiation documentation, including Design Substantiation Reports (DSR) providing the assurance and evidence to enable confidence in our technical solutions
  • Reviewing safety case documentation and identifying potential shortfalls in the design
  • Liaising with both internal and external designers and equipment vendors to gather information
  • Interrogating the Engineering Schedule and evidencing claims made against Systems, Structures, and Components (SSC) in the documentation
  • Interfacing with other stakeholders such as Human Factors, Fire Safety, Criticality, Radiological and the client Technical Authority
What we offer
What we offer
  • Competitive salary package
  • Innovative, collaborative and inclusive environment
  • Flexible working including hybrid and core hours patterns
  • Professional and skills based continued development though training and mentoring
  • Professional Membership fees
  • Employee share scheme
  • EV salary sacrifice scheme
  • Health Shield Cover
  • Modern offices with on-site gym, café (Chorley Head office)
  • Social events, charity fundraising events throughout the year
  • Fulltime
Read More
Arrow Right

Mechanical Engineer (Senior or Principal)

We are looking for an experienced Senior or Principal Mechanical Engineer with s...
Location
Location
United States , Plymouth
Salary
Salary:
Not provided
Uni-Systems Engineering
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • Must qualify as a U.S. person under ITAR due to access to export-controlled technical data
  • B.S. degree in Mechanical or Aerospace Engineering from an ABET-accredited school, with 5+ years of experience for Senior level and 7+ years for Principal level
  • Managed risks associated with custom designs
  • Collaborated with clients' input to innovate and creatively solve multifaceted problems
  • Knowledge of current codes and requirements that apply to the Mechanical Engineering discipline
  • Advanced understanding of engineering software including modeling and analysis
  • most advantageous being SolidWorks, Solidworks Simulation, MathCAD, Ansys, GD&T
  • Desire to solve mechanical problems including everything from bearings to actuator sizing with a system level focus
  • Proficient at using analysis software
  • Independently determines and develops approach to solutions and work under general direction
Job Responsibility
Job Responsibility
  • Design of complex machinery including gearing, actuators, wheels, weldments, bearings, and related assemblies
  • Contribute to development of concepts and engineering designs, producing engineering calculations as required for projects and design development of systems
  • Serve as Project Engineer for various projects, overseeing all aspects of design and implementation
  • Maintain regular communication with clients to ensure project objectives and expectations are met
  • Develop and manage design budget and schedules, ensuring timely and cost-effective project completion
  • Lead and coordinate the design team to meet project goals, deadlines and deliverables
  • Participate in scheduled design reviews with contractors, architects, engineering consultants, and other project team members to ensure alignment and resolve issues
  • Interface with other departments to coordinate structural systems with electrical and mechanical systems
  • Provide project status updates during Project Review Meetings and other company meetings
  • Coordinate with field personnel and purchasing to determine and obtain required components
What we offer
What we offer
  • Competitive salary and growth opportunities
  • Comprehensive benefits package including medical, dental, vision, life, and disability insurance
  • 401(k) plan with above-market company matching
  • Generous paid time off (PTO) and paid company holidays
  • HSA and FSA options
  • A collaborative culture built on integrity, respect, innovation, value and enterprise
  • Fulltime
Read More
Arrow Right

Mechanical Engineer - Water / Wastewater (Senior / Principal)

Egis is expanding rapidly in the UK, backed by a global team of more than 20,500...
Location
Location
United Kingdom , Manchester
Salary
Salary:
Not provided
egis-group.com Logo
Egis in the UK
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • BEng/MEng (or equivalent) in Mechanical Engineering
  • Registered as a chartered engineer (CEng) or equivalent professional membership (e.g., IMechE or similar)
  • Strong track record in the UK regulated water market, focused on municipal water and/or wastewater treatment
  • Demonstrated leadership across the design lifecycle: feasibility/optioneering, concept, outline and detailed design, plus support through delivery stages as the designer
  • Practical depth in treatment mechanical engineering: selecting and specifying equipment, integrating packaged plant, and producing/reviewing high-quality design documentation
  • Working knowledge of UK water industry standards, regulatory expectations, and safety-by-design/CDM as applied to treatment facilities
  • Experience supporting projects delivered via frameworks, alliances and/or D&B models, including design review, technical query response, and design assurance
  • Confident client and stakeholder manager
  • clear communicator, comfortable presenting, and able to lead technical conversations with credibility
  • Evidence of BD/work-winning contribution (or strong demonstrable aptitude): opportunity shaping, bid inputs, client development, and service-line growth
Job Responsibility
Job Responsibility
  • Lead the mechanical design of municipal water and wastewater treatment projects across the UK, covering feasibility, optioneering, concept, outline and detailed design across major programmes (e.g. AMP8, WINEP, SROs, etc)
  • Set and uphold the mechanical design approach for treatment work: in-house standards (in line with water industry asset standards), checking, and consistency of outputs across projects and teams
  • Fulfil Designer duties under CDM 2015 for mechanical works, ensuring effective hazard identification and risk reduction and, where designated, supporting or undertaking Principal Designer responsibilities on assigned projects
  • Take ownership of the mechanical scope within multidisciplinary delivery, driving clear decisions on operability, maintainability, access, and whole-life performance
  • Produce and quality-check core mechanical outputs such as equipment selection, specifications, datasheets, calculations, schedules, and design narratives (e.g., pumping and packaged plant where relevant)
  • Act as a senior client-facing technical lead, running workshops and design reviews, advising clients, and building long-term relationships with regulated water stakeholders
  • Provide design assurance and technical support during delivery phases, including reviewing contractor submissions, answering design queries, and supporting handover/commissioning activities when required
  • Grow the mechanical capability through business development and work winning: identify opportunities, shape scopes, contribute to bids, and build a healthy forward pipeline
  • Help translate the UK water growth strategy into practical actions: target sectors, priority accounts, capability gaps, and delivery plans focused on treatment
  • Build the mechanical arm of the UK water consultancy team through recruitment, mentoring and skills development, including pathways, coaching and technical governance
What we offer
What we offer
  • An exciting new growth role in a fast‑organic growing UK business, offering clear and accelerated career progression
  • Top Employers 2025 certification
  • A global leader in green infrastructure
  • Highly competitive leadership‑level reward package
  • Hybrid and flexible working
  • 26+ days annual leave plus bank holidays
  • Professional development, chartership support & global mobility
  • Supportive, inclusive culture driven by sustainability and long‑term community impact
  • Fulltime
Read More
Arrow Right

Mechanical Engineer - Water / Wastewater (Senior / Principal)

As our Mechanical Engineering Lead, you’ll take a national leadership position s...
Location
Location
United Kingdom , Bristol
Salary
Salary:
Not provided
egis-group.com Logo
Egis in the UK
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • BEng/MEng (or equivalent) in Mechanical Engineering
  • Registered as a chartered engineer (CEng) or equivalent professional membership (e.g., IMechE or similar)
  • Strong track record in the UK regulated water market, focused on municipal water and/or wastewater treatment
  • Demonstrated leadership across the design lifecycle: feasibility/optioneering, concept, outline and detailed design, plus support through delivery stages as the designer
  • Practical depth in treatment mechanical engineering: selecting and specifying equipment, integrating packaged plant, and producing/reviewing high-quality design documentation
  • Working knowledge of UK water industry standards, regulatory expectations, and safety-by-design/CDM as applied to treatment facilities
  • Experience supporting projects delivered via frameworks, alliances and/or D&B models, including design review, technical query response, and design assurance
  • Confident client and stakeholder manager
  • clear communicator, comfortable presenting, and able to lead technical conversations with credibility
  • Evidence of BD/work-winning contribution (or strong demonstrable aptitude): opportunity shaping, bid inputs, client development, and service-line growth
Job Responsibility
Job Responsibility
  • Lead the mechanical design of municipal water and wastewater treatment projects across the UK, covering feasibility, optioneering, concept, outline and detailed design across major programmes (e.g. AMP8, WINEP, SROs, etc)
  • Set and uphold the mechanical design approach for treatment work: in-house standards (in line with water industry asset standards), checking, and consistency of outputs across projects and teams
  • Fulfil Designer duties under CDM 2015 for mechanical works, ensuring effective hazard identification and risk reduction and, where designated, supporting or undertaking Principal Designer responsibilities on assigned projects
  • Take ownership of the mechanical scope within multidisciplinary delivery, driving clear decisions on operability, maintainability, access, and whole-life performance
  • Produce and quality-check core mechanical outputs such as equipment selection, specifications, datasheets, calculations, schedules, and design narratives (e.g., pumping and packaged plant where relevant)
  • Act as a senior client-facing technical lead, running workshops and design reviews, advising clients, and building long-term relationships with regulated water stakeholders
  • Provide design assurance and technical support during delivery phases, including reviewing contractor submissions, answering design queries, and supporting handover/commissioning activities when required
  • Grow the mechanical capability through business development and work winning: identify opportunities, shape scopes, contribute to bids, and build a healthy forward pipeline
  • Help translate the UK water growth strategy into practical actions: target sectors, priority accounts, capability gaps, and delivery plans focused on treatment
  • Build the mechanical arm of the UK water consultancy team through recruitment, mentoring and skills development, including pathways, coaching and technical governance
What we offer
What we offer
  • Hybrid and flexible working
  • 26+ days annual leave plus bank holidays
  • Professional development, chartership support & global mobility
  • Supportive, inclusive culture driven by sustainability and long‑term community impact
  • Fulltime
Read More
Arrow Right