Commercial Design Engineer

This document is a model job description for a design engineer working on commercial and industrial solar PV installations. It has been developed by Solar Energy UK’s Skills and Workforce Steering Group and sets out the key responsibilities of the role, as well as the skills and qualifications expected.

Role Purpose

The Design Engineer will be responsible for the technical design, performance optimisation, and documentation of solar photovoltaic (PV) systems, from concept through to detailed engineering. This role involves close collaboration with clients, stakeholders, and multidisciplinary teams to deliver efficient, compliant, and commercially viable renewable energy solutions.

Key Responsibilities

Client Liaison & Requirements Gathering

Engage with clients to understand specific project needs.

Ensure all designs comply with the latest regulatory standards and industry best practice.

Financial and Technical Feasibility

Support cost analysis and budget preparation for PV system designs.

Prepare revenue projections and assess economic viability.

Site Assessment & Feasibility Studies

Requirements will depend on whether the solar project is ground-mounted, rooftop, carport, or floating.

Gather and analyse site information, either through direct site visits or by obtaining and reviewing specialist reports, surveys, and data to evaluate the suitability of solar projects, including:

Ground-mounted (e.g. land topography, soil/ground conditions, access, and potential grid connection options).  

Rooftop (e.g. roof structure & type, load-bearing capacity, orientation, shading, condition of building fabric, safe access and grid connection options).

Carport (e.g. site layout, parking usage, structural design requirements, and integration with charging infrastructure).

Floating (e.g. water body suitability, anchoring systems, water quality and ecology, and specific safety requirements).

As necessary assess environmental impacts, biodiversity considerations, water resources, and cumulative effects.

Develop decommissioning plans and recommend security and safety measures.

Stakeholder Collaboration

Complete Distribution Network Operator (DNO) applications and liaise with planning authorities, consultants, and local government.

Work with equipment manufacturers, structural engineers, and survey teams.

Provide technical support to project managers and installation teams during construction.

System Layout & Positioning

Design PV layouts that maximise energy yield while meeting planning, structural, and environmental constraints.

Perform shading analysis, terrain modelling, and cable routing optimisation.

Ensure compliance with local zoning, building codes, and environmental regulations.

Structural Design

Specify safe and efficient mounting systems considering environmental and site-specific conditions.

Conduct structural calculations and material selection for long-term stability.

Detailed System Design

Prepare compliant designs in line with UK regulations, fire safety, and health & safety requirements.

Perform yield simulations, loss analysis, and ensure designs allow for future maintenance.

Component Selection

Select solar modules, inverters, mounting structures, and balance-of-system components suited to site conditions and project goals.

Performance Optimisation

Use specialist software for performance modelling and system optimisation.

Design monitoring solutions for energy flow, inverter parameters, and client load tracking.

Technical Documentation & Drawings

Produce single-line diagrams (SLDs), schematics, earthing designs, and as-built documentation.

Maintain document control systems and compile O&M manuals, safety plans, and grid connection applications.

Electrical System Design

Complete DC and AC system designs, including cable sizing, switchgear specification, and meter selection.

Integrate Battery Energy Storage Systems (BESS) and perform operational data analysis.

Protection Systems Design

Specify overload protection, grounding, earthing, and lightning protection systems.

Develop fire safety and grid protection schemes, ensuring compliance with standards.

Incorporate cybersecurity, monitoring, and emergency response planning into designs.

Skills & Experience

Essential:

Proven experience designing grid-connected solar PV systems.

Strong understanding of UK regulations, DNO processes, and health & safety requirements.

Proficiency with PV design software (e.g. PVsyst, AutoCAD, Helioscope) and Microsoft Office Suite.

Ability to produce high-quality technical drawings and reports.

A good understanding of BS 7671 requirements for electrical installations.

Desirable:

Degree in Electrical, Mechanical, Renewable Energy Engineering, or related discipline (please note that there is variation within the industry as to whether a degree qualification is required for this role, for some companies it will be Desirable and for others it may be Essential).

Level 3 Award in BS 7671 Requirements for Electrical Installations (current edition).

Experience with Battery Energy Storage Systems (BESS).

Knowledge of environmental assessment processes.

Familiarity with ISO9001 quality management systems.

Key Attributes

Strong analytical and problem-solving skills.

Excellent communication and stakeholder management abilities.

Detail-oriented with a commitment to accuracy.

Proactive, adaptable, and able to work to tight deadlines.

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